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Paving, Kerb and Retaining Wall

Handbook

Expect the Best


Disclaimer: Although the information in this book is presented in good faith and believed to be correct, Bosun makes no representations or warranties as to the completeness or accuracy of the information including variances in colour, size, texture and weight. Due to different aggregates used in various regions, variances will occur. Version 5, Printed January 2017


Expect the Best

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This book is best used in conjunction with our website www.bosun.co.za

The pictures in this brochure, although not digitally enhanced, are nevertheless professional photos taken from optimum angles and make for beautiful viewing. The reality is that when these sites are seen in real life they may appear less than picture perfect due to the influences of outdoor conditions.

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Contents Paving Introduction Modern residential designs Modern commercial designs Sidewalks Roads Permeable paving

5-9 10-29 30-57 58-59 60-61 62-63

Paving Products Colour chart Beneficiated finishes Products

65 66-67 68-89

Kerbs Dry cast kerbs versus wet cast kerbs Innovation Precast solutions Installation and specification Products

92-93 94-95 96-97 98-99 100-105

Retaining Wall Blocks Robust Block Versoblock Installation guidelines Design concepts

108-115 116-119 120-123 124-127

Information - Buying and Installing Paving Things you should know about paving prior to installation Paving material comparison Efflorescence Selecting the right contractor Laying patterns Installation guidelines Waterwise paving installation guidelines Common paving installation problems Maintenance Guarantee Installation tools Product specifications

129 130-131 132-133 134-137 138-147 148-152 153-156 157 158-160 161 162-165 166

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Paving


Paving: Introduction

South African National Standard for concrete paving bricks explained The South African National standard for concrete paving blocks is SANS 1058: 2012. Bosun’s factories in Midrand, Brits and PE are amongst the first manufacturers of concrete paving blocks to be awarded the SANS 1058: 2012 mark. All our factories manufacture products according to the required specifications and product guarantees are based on them. Bosun kerbs and retaining wall blocks also comply with the South African National Standard as tested by the CMACS and other independent accreditation bodies.

What does it mean if paving blocks comply with the National Standard? • The manufacturer has an equipped laboratory and tests batches of manufactured blocks. • Blocks comply with strength specifications which are tested by means of tensile splitting. • Blocks comply with abrasive resistance specifications. This means that blocks are only allowed a specified amount of “damage” due to friction. • Blocks are allowed only minimal dimensional variances. • The visual quality of the blocks should be acceptable. A customer has recourse if necessary when it comes to the quality of paving blocks.

The fully equipped testing facility at Bosun Midrand. (All Bosun branches have fully equiped testing facilities).

Proud member of: The Concrete Manufacturers Association The CMA regulates and monitors technical standards on precast concrete products. Complying with these standards assures members that their products maintain their integrity, accuracy and quality. CMA members who don’t comply with the stipulated standards would be at risk of losing their CMA membership. Bosun can confidently assure the paving industry that it adheres strictly to the stipulated CMA standards and regulations with zero tolerance for deviation regarding their precast concrete products and thereby confidently guarantees its products in terms of quality and integrity.

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Paving: Introduction State-of-the-art manufacturing equipment Bosun pavers are manufactured exclusively on Hess Machines and SR Schindler machines are used for beneficiated finishes. These companies form part of the ‘Top Werk’ group, one of the world’s leading manufacturers of precast concrete equipment. The weak South African Rand makes it more expensive to invest in this equipment but we strongly believe that the accuracy of these machines as well as their up to date technology produces a product which is vastly superior to the average cheaper alternatives.

Transport A specialised fleet of trucks are contracted to Bosun. These vehicles are equipped with air suspension and aluminium decks to ensure a rigid, flat loading surface and the softest ride possible. In addition, all trucks are equipped with state of the art cranes in order to offload quickly and efficiently, again minimising the risk of damage to products. Be aware that inferior delivery vehicles will cause damage to pavers in transit.

Expertise Owning the best manufacturing equipment is one thing. However real value is only added by the expertise of the people operating that equipment. Bosun has employed the expertise of Industry Leading European Consultants and invested heavily in staff development and training both locally and with overseas partners. This has resulted in a product offering consistent with leading European manufacturers. Jochen Meyer, one of Bosun’s European associates and block making consultants.

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Larger paver sizes

Standard Brick

BOSUN Pavers

Many of our dry cast pavers are much larger than traditional South African paving bricks. Wet cast concrete manufacturers have traditionally been known for the production of large ‘flagstones’, which could be viewed as similar in size to Bosun’s large pavers. However dry cast slabs offer the following advantages over traditional wet cast flagstones: • Guaranteed to be dimensionally more accurate than wet cast flagstones. • Non-tapered edges for more accurate installation and smaller jointing gaps. • Nibs for accurate installation.

Manufacturing technology Bosun manufactures a double layer paver offering a ‘base’ layer which is focussed on structural integrity while the ‘topping’ layer provides a smooth, attractive finish which focuses on abrasive resistance.

Guarantee Bosun offers a 5 year guarantee on their products. See the detailed guarantee on page 161

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Paving: Introduction

Beneficiated Concrete Finishes Bosun offers concrete pavers with various beneficiated finishes or surface textures, which are new in South Africa and exclusive to Bosun. These finishes are achieved by means of technical processes with specialised machinery and equipment as shown below in these highly simplified graphic representations.

Ground Pavers The Grinding of concrete involves cutting the surface or ‘face’ of the concrete with a series of diamond tipped blades creating a fairly smooth texture. The smoothness of the surface texture is dependent on the use and application of the amount of cutting blades being used. The desired outcome of this process is to expose stones with interesting natural colours on the surface of the pavers. The difference between Grinding, Washed and Shot Blast is that stones on the surface of Ground pavers are perfectly flat and smooth whereas stones exposed by means of Washing or Shot Blasting will still have a naturally rounded shape. Grinding is an expensive process due to blade costs.

Shot Blast Pavers The Shot Blasting process involves peppering pavers or kerbs with ‘Shot’ or small beads of steel which are fired at high velocity by means of compressed air. The Shot actually dents the surface of the product bit by bit thereby dislodging small particles of concrete which then fall away. This exposes small stones and other aggregates on the surface. In a sense the result is similar to that of washed pavers as described opposite but a Shot Blast texture is slightly smoother although more irregular than a Washed texture.

Ground and Shot Blast Pavers These pavers are ground and then lightly shot blasted in order to provide a rougher surface texture.

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Washed or Exposed Aggregate Pavers In the washing process fine cement particles are removed from the paver’s surface with a special water spraying technique which exposes beautiful small stones in various colour schemes, creating interesting and hard-wearing surface textures.

Chamfered Pavers Chamfering is a process where an angled edge is cut on the paver. This could be done on any one, or all of the edges.

Calibrated Pavers Calibration is a process whereby the bottom of a paver is cut with a diamond tipped blade in order to create a thickness which is dimensionally accurate and consistent. It is almost impossible to manufacture large pavers and maintain accurate and consistent heights. The SANS height variance specification on large pavers is Âą5mm. This could result in a 10mm variance between two adjacent pavers which are however still within the specified range. All large paving stones should be calibrated prior to resale.

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Paving: Modern residential designs

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Paving: Modern residential designs

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Grass or other ground cover is used as an integral part of this permeable paving system. By planting ground cover in the holes designed in these pavers, a green surface is created. Grass will not be damaged by cars driving or parking on these pavers.

Reality check It is more expensive and requires more skill to install permeable paving.

Paving tip The best paving will fail when it is installed incorrectly. Select your installer very carefully and remember it is more expensive to install paving properly and correctly but it will pay off in the long run. (Refer to page 134)

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Paving: Modern residential designs

Paving tip Large pavers are more difficult and more expensive to install. When using large pavers on driveways, special care should be taken with the earth preparation.

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Venetian Pavers in grey and black Large Urban Pavers in granite

Reality check Concrete paving’s colour will fade over time. Dust engrained into capillaries could also dull the paving. The colour of the paving will appear to be more vibrant after rainfalls.

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Paving: Modern residential designs Bosun XXL Urban Pavers used as stepping stones. Their 900mm width allows for enough space to walk on comfortably.

Paving tip Paving blocks are heavy, difficult to transport and handle. Always bear in mind the cost of delivery when purchasing paving.

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Large Urban Pavers in marble. Large Urban Pavers in granite.

Paving tip Exercise caution when using cement grouting as it could permanently stain your paving and it could also crack or break up in time to come. The best and proven fixed grouting material is polymer grouting like Romex which is available from Bosun.

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Paving: Modern residential designs

Ground Black Urban Pavers in a combination of sizes

Paving tip Installation of paving will most probably cost more than what was originally anticipated. If paving is to last for a lifetime avoid taking shortcuts.

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Reality check Paving blocks take some time to settle on a site before they look their best. Allow about six months for colours to settle. Efflorescence is also most likely to appear within the first year of installation.

Paving tip Do not use red plaster sand for jointing. It will stain your pavers. Light plaster sand is less common but a much better choice to use for grouting.

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Paving: Modern residential designs

Paving tip Bosun pavers can be sealed with a water based sealant. This will enhance the colour and protect the paved surface. Beware of sealing pavers prior to the appearance of efflorescence as this will trap the efflorescence within the paving. Also be cautious when sealing driveways as warm tyre residue could bond with the sealant causing unsightly marks.

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Reality check It requires more skill to install intricate designs. Always consider the thickness of pavers when using a variety of pavers in conjunction with each other. It complicates matters when one paver is thicker or thinner than the others.

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Paving: Modern residential designs

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Reality check Combination patterns are more difficult to install, requiring more skill and therefore customers can expect to pay more for this type of installation.

The Urban range of pavers is available in various sizes which could be used to install in combination with each other. (The pavers on this page were sealed with a water based sealant.)

Paving tip The use of a large plate compactor is recommended for the levelling of combination patterns. Small compactors will bed smaller pavers deeper than larger pavers.

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Paving: Modern residential designs Traditionally concrete paving bricks or ‘cement bricks’ have satisfied the price conscious segment of the market. Many paving contractors would deliver a sales pitch such as, “Clay bricks will cost you x amount. If you are looking for something a bit classier simulated stone or ‘SmartStone’ is an option but it is more expensive. However the cheapest option we can offer you is cement bricks.” This has changed in the past five years. Modern manufacturing equipment and increased technical proficiency has enabled concrete paving manufacturers to produce unique products and remarkable finishes at the upper end of the scale.

Paving tip Never install plastic sheeting under paving as it badly affects the base structure. Plastic sheeting DOES NOT prevent weeds from growing. Weeds grow when seeds are deposited from above into the joints between pavers.

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Paving tip Structural integrity of a paving installation comes from good compaction of layer works beneath the paving and not the paving blocks themselves. When using base material found on site, it must be excavated and compacted in layers using a heavy roller.Â

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Paving: Modern residential designs

XXL Pavers by Bosun Bosun XXL pavers are 27 times larger than standard paving bricks. This type of paving is new to South Africa and because of their size require special equipment and skill to install. This paver’s size is 900mm x 600mm and the blocks weigh more than 90kg each.

Paving tip Pavers are fragile and should be handled with care. They should never be thrown or tipped out of wheelbarrows.

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Paving tip When it comes to paving, what goes on underneath your paving is more important than the visible paving. Consult our installation section in the back of this book for necessary questions to ask your installer. (Refer to page 134)

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Paving: Modern residential designs

Paving tip It is likely that your pavers will be affected by efflorescence in their lifetime. It is a temporary natural white film that appears on concrete, clay or natural stone but will however eventually disappear on its own. See page 132 of this brochure for a comprehensive take on efflorescence.

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Reality check Tyres leave marks on any type or colour of paving. Darker colours will hide it better but marks will still appear.

Slimline Urban Pavers

Paving tip When your paving is jointed with sand, top up your joints by sweeping dry plaster sand over your paving from time to time. Always sweep diagonally across the paving.Â

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Paving: Modern commercial designs

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Paving: Modern commercial designs

Copperleaf Clubhouse

Paving tip Bosun recommends that an engineer should design the layer works of any commercial paving project.

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Design by Uys and White Landscape Architects

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Paving: Modern commercial designs

Nedbank Menlyn Main

Design by InterDesign Landscape Architects

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Speak to Bosun about special paving elements like tactile pavers, walkway demarcations and concrete bollards.

Reality check Your project is likely to be affected by efflorescence in its lifetime. Expect this and make the investor aware of it. It is a temporary phenomenon in concrete, clay and natural stone and will eventually disappear. Refer to page 132 for a comprehensive take on efflorescence.

Paving tip Be careful when using power washers to clean paving as this could blast the jointing sand out of the paving joints.

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Paving: Modern commercial designs

Afrisam Head Office

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Reality check Combination patterns are more difficult to install, requiring more skill and therefore customers can expect to pay more for this type of installation.

Paving tips Bosun has various textures and colours available in order to create flow and demarcation in landscaping designs. Avoid grouting pavers with red plaster sand as it will stain your paving.

Design by S.E.F. Landscape Architects

Paving on steep slopes is more complex than level areas. Use edge restraints and pay special attention to layer works on such installations.

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Paving: Modern commercial designs

Menlyn Podium

Design by Uys and White Landscape Architects

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Paving tip Bosun’s sister company, SmartStone, produces wet cast pavers, cobbles and flagstones with contrasting textures to Bosun pavers. These could easily be incorporated into Bosun’s paving designs.

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Paving: Modern commercial designs

Alice Lane

Design by Insite Landscape Architects

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Paving tip Installation of paving could be an art when executed by a real craftsman. A design will only be as good as its installation. A craftsman would be more expensive but the end result will be worth it.

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Paving: Modern commercial designs

Mall of Africa

Designed by Daniel Rebel Landscape Architects

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Reality check Discolouration of concrete can be seen on bridges, road barriers, kerbs and paving. There are various causes but natural colour variations are a characteristic of concrete as a building material. Don’t expect paving which is exposed to and installed in the African elements to look like ceramic tiles. It definitely won’t!

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Paving: Modern commercial designs

Cell C

Paving tip SmartStone, Bosun’s sister comany has various copings and bollards which could be used in conjunction with Bosun pavers. Paving is porous. Before site completion there is a big risk that paving might be stained by the red soil found in many areas in Gauteng. Contractors transferring it with their feet and rain storms are usually the main culprits. Therefore it is ideal to install paving as late as possible in a project’s development although this is not always practically possible.

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Design by Insite Landscape Architects

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Paving: Modern commercial designs

Nelson Mandela Square

Design by Bentel and Associates

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Paving tip Bosun offers various unique surface textures in order to create your desired effect. At Nelson Mandela square the architect envisaged the use of pavers with an aged appearance. In order to create this appearance these pavers underwent a grinding process where specially selected aggregates were exposed in the surface texture. After this process the pavers underwent a light shot blast where they were peppered with small steel balls in order to roughen up the surface and further enhance the texture.

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Paving: Modern commercial designs

Waterfall Lifestyle Centre

Design by Daniel Rebel Landscape Architects

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Paving tip Pavers should be levelled with a plate compactor or in the case of large pavers with a large rubber mallet. A plate compactor should however always be used when ‘shaking’ jointing sand into joints.

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Paving: Modern commercial designs

Trumpet on Keyes Rosebank

Designed by StudioMAS Architecture and Urban Design

Paving tip Installing paving on a concrete slab e.g. above underground parking is very specialised. Always consult an engineer for such designs.

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Reality check Concrete is porous. Fine dust might settle in its capillaries and paving will appear dull. Regular washing of pavers might be required in order to restore its vibrance.

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Paving: Modern commercial designs

Summit Place

Design by Uys and White Landscape Architects

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SmartStone cobbles were used to good effect in this project to demarcate parking areas.

Paving tip Bosun recommends the use of interlocking shaped pavers in areas with heavy vehicular traffic.

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Paving: Modern commercial designs

BMW Head Office

Reality check XXL Urban pavers are extremely heavy and therefore very difďŹ cult to install. Please speak to your Bosun representative about special tools we have available to simplify the installation of these large pavers.Â

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Design by African Environmental Design

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Paving: Modern commercial designs

Newtown Junction

Design by Daniel Rebel Landscape Architects

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Paving tip Natural surface textures are created by means of specially selected aggregates. The pavers used in this project underwent shot blasting that exposed small stones which, in the process created a slip resistant yet unique external floor.

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Paving: Sidewalks

Sidewalks in Tshwane

Sidewalks in Vilakazi Street Soweto

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Bosun pavers are also widely used for sidewalks within private developments.


Red sidewalks in Soweto In 2006, in commemoration of the 30th anniversary of the June 16 student uprising in Soweto, the route from Morris Isaacson High School to the Hector Pieterson Memorial was paved with red pavers. This was the first stage of a broader project to pave all the routes learners took on 16 June 1976 on their way to Orlando West, where the violent confrontation with the police took place. Red pavers were initially chosen to symbolise the bloody sacrifice made by the students on this day and in those days immediately after. Over the years this project evolved and is currently also linked to the beautifying and greening of Soweto. Many of the routes in commemoration of June 16 have been completed while the red sidewalks have almost become a Soweto trademark. The plan is to eventually have paved sidewalks throughout Soweto that will serve its community more effectively.

Sidewalk in Sandton CBD

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Paving: Roads

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Numerous municipal, provincial and even national roads (including toll gates) have been paved with Bosun Interlocking Pavers. Segmented block paving is popular for use on roads because: • Segmented block paving is not susceptible to potholes • Creates local jobs for communities • Creates a sense of ownership for local communities. Municipalities where Bosun paving has been used in the recent past: • Johannesburg • Rustenburg • Tshwane • Madibeng • Ekurhuleni • Moses Kotane • Lesedi • Govern Mbeki • Emfuleni • Dr Moroka • Nelson Mandela Bay • Chris Hani • Cacadu • Phumelela • Nkonkobe • Mangaung

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Paving: Permeable paving Permeable paving is a paved surface through which water is able to pass between the blocks. The benefits of a permeable paving system is: It assists storm water drainage systems; natural breakdown of pollutants; water harvesting and prevents soil erosion. The Bosun Waterwise Paver™ has four different installation techniques allowing for optional levels of permeability. With the correct design water could either infiltrate the subgrade (ground), or be channelled to an underground storage facility, which has proved itself to be an extremely effective means of water harvesting.

Reality check It is way more expensive and requires much more skill to install permeable paving. Â

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These pictures were taken at the same time on a rainy day. This site is installed with Bosun Waterwise Pavers and normal Interlockers. It can be seen that water has drained through the permeable paving in the parking area whereas the water has dammed up on the standard interlocking paving. This site has a system of underground pipes and an underground catchment tank in which rain water is harvested for irrigation.

Reality check A permeable paving system requires an engineer’s design and very specific layer works to function correctly.

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Paving products


Paving: Products

Colour Chart Not all products are available in all the colours below. Please consult your Bosun representative. Our blended colours vary from paver to paver, creating a random organic effect. We recommend viewing a number of sample pavers together in order to perceive the holistic picture of any one colour. (Feel free to visit our factories where we will assist you in this regard.) Please note: Due to photographic and printing processes the colours in this catalogue may not be a hundred percent accurate. Concrete is made from natural products which are mined and crushed and the resulting aggregates are never exactly the same colour. These differences do reflect in the final products in the form of slight colour variations. It is therefore recommend to mix pavers from different packs when doing an installation. Red

Marble A blend of grey, black, tan and white.

ONLY AVAILABLE IN THE URBAN RANGE Grey

Granite A blend of grey, black and white.

ONLY AVAILABLE IN THE URBAN RANGE Black

Autumn Blend A blend of red, black and tan .

Tan

Sahara

Please note: It is more difficult to achieve colour consistency with tan pavers, therefore more prominent variances will exist.

A blend of tan and black

Brown

Multiblend A blend of red and black

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Paving: Products

Beneficiated finishes Bosun’s Beneficiated finishes and textures are new and never seen before in South Africa.

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Ground Tan

Ground Red

Ground Grey

Ground Black

Ground Shot Blast Black


Washed White

Shot Blast White

Washed Black

Shot Blast Black

Washed Tan

Shot Blast Tan

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Paving: Products

Bevel Bond Paver A traditional brick shaped paver with bevelled edges. This product is 50mm thick and is the most cost effective paving solution for residential driveways and walkways.

Dimensions Height Mass per Paver SANS Pavers per m2

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200mm x 100mm 50mm Âą 2.15kg 1058: 2012 Approved 50


Split Bevel Bond Paver A smooth surfaced paver with bevelled edges which creates the impression of 100mm x 100mm cobbles when installed.

Dimensions Height Mass per Paver SANS Pavers per m2

200mm x100mm 50mm Âą 2.15kg 1058: 2012 Approved 50

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Paving: Products

Rio Rocoso Bevel The Rio Rocoso Bevel has the appearance of a ripple surfaced cobble with bevelled edges.

Dimensions Height Mass per Paver SANS Pavers per m2

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200mm x 100mm 50mm Âą 2.15kg 1058: 2012 Approved 50


Bosun Cobble This paver creates the impression of 150mm x 150mm cobbles when installed. It is manufactured in a double paver shape in order to create better interlocking when installed, compared to smaller square cobbles.

Dimensions Height Mass per Paver SANS Pavers per m2

300mm x150mm Gauteng: 60mm PE branch: 55mm Âą 5.8kg 1058: 2012 Approved 22.2

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Paving: Products

Venetian Paver This paver is slimmer and longer than a traditional paving brick in order to create a totally unique design.

Dimensions 255mm x 55mm Height 60mm Mass per Paver Âą 1.90kg SANS 1058: 2012 Approved Pavers per m2 72.7 Not available at PE branch

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Smooth Ethnic Paver This bevelled paver is slightly larger than a standard paving brick.

Dimensions Height Mass per Paver SANS Pavers per m2

200mm x 150mm 55mm Âą 3.7kg 1058: 2012 Approved 33

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Paving: Products

Urban Paver A Non-Bevelled Paver Range available in various sizes that could be installed in combination with each other or singularly.

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Standard Brick

Urban range

XXL Dimensions 900mm x 600mm Height 80mm Mass per Paver ± 95kg SANS 541 1.85 Pavers per m2 Not available at PE branch

Large Dimensions Height Mass per Paver SANS Pavers per m2

Slimline Dimensions 400mm x 200mm Height 60mm Mass per Paver ± 11kg SANS 541 Pavers per m2 13 Not available at PE branch

Medium Dimensions 200mm x 150mm Height 60mm Mass per Paver ± 3.7kg SANS 1058: 2012 Approved Pavers per m2 33.33 Not available at PE branch

400mm x 300mm 60mm ± 17.5kg 541 8.33

Small Dimensions 200mm x 100mm Height 60mm Mass per Paver ± 2.6kg SANS 1058: 2012 Approved Pavers per m2 50 Not available at PE branch

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Paving: Products

Linneo Paver These large rectangular pavers are available in two sizes and create a seamless, modern feel. Install them in combination with each other or singularly. A linear, staggered stretcher bond pattern is recommended.

Small Dimensions Height Mass per Paver SANS Paver per m2

300mm x 120mm 80mm Âą 6.5kg 1058 : 2012 27.77

Large Dimensions Height Mass per Paver SANS Pavers per m2

600mm x 240mm 80mm Âą 23kg 541 6.94

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Standard Brick

Linneo Range

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Paving: Products

Grass Blocks Grass or other ground cover is used as an integral part of this permeable paving system. This system is also used for the prevention of soil erosion.

Dimensions Height Mass per Unit SANS Pavers per m2

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600mm x 400mm 100mm + 35kg N/A 4.2


Rio Rocoso Interlocking Paver Designed to ‘lock’ together when installed, this paver has the appearance of a ripple surfaced cobble with bevelled edges. It combines the functionality of interlockers with the aesthetic appeal of a cobble.

Dimensions 200mm x 100mm Height 60mm/80mm Mass per Paver + 2.6kg SANS 1058: 2012 Approved Pavers per m2 50 80mm available at PE branch only

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Paving: Products

60mm Interlocking Paver An interlocking paving brick, ideal for commercial applications. Interlocking pavers are robust, provide hard-wearing durability and a multitude of further functions.

200mm x 100mm Dimensions 60mm Height Mass per Paver Âą 2.6kg 1058: 2012 Approved SANS 50 Pavers per m2 Not available at PE branch

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80mm Interlocking Paver This is an interlocking paving brick for industrial or heavy commercial applications where trucks, forklifts and other heavy machinery are prevalent. This paver has also been used extensively on municipal roads.

Dimensions Height Mass per Paver SANS Pavers per m2

200mm x 100mm 80mm Âą 3.5kg 1058: 2012 Approved 50

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Paving: Products

Hermetic Flagstones The textures and colours of Bosun Hermetic Pavers are derived from real stone. These flagstones have straight edges that allow for less obtrusive jointing gaps. Their dense surface make them easy to clean, non-slip and durable for use on building aprons, piazzas as well as pool areas and patios.

Dimensions 400mm x 400mm Height 35mm Mass per Paver Âą12kg SANS 541 Pavers per m2 6.25 Not available at PE branch

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Paving: Products

Waterwise Paver Bosun has pioneered the innovative registered design Waterwise paving system.

Designed for permeable paving systems, this paver anchors itself to adjoining pavers leaving gaps between the joining areas through which water is able to drain. The Bosun Waterwise Paver™ could be used in 4 different installation options, determined by the level of permeability required because of its unique registered design. With the correct design, water could either infiltrate the subgrade (ground), or be channelled to an underground storage facility, which has proved to be an extremely effective means of water harvesting.

Dimensions 239mm x 209mm Height 60mm Mass per Paver Âą4.35kg SANS 1058: 2012 Approved Pavers per m2 Varies according to permeability (ref pg144) Not available at PE branch

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Citylock Paver An interlocking paver that resembles smaller and larger pavers installed in a pattern using two different sized pavers.

Dimensions 230mm x 140/90mm Height 60mm/80mm Mass per Paver ¹3.5kg SANS 1058: 2012 Approved Pavers per m² 39 Not available at PE branch

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Paving: Products

Permeable Citylock An interlocking paver that resembles smaller and larger pavers installed in a pattern. This paver is similar in appearance to the Bosun Citylock paver but offers permeability and can be used in conjunction with the original Citylock paver as illustrated below.

Dimensions 230mm x 140/90mm Height 60mm/80mm Mass per Paver Âą3.5kg SANS 1058:2012 Paver per m2 39 Not available at PE branch

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Laying Patterns Permeable Citylock

Citylock

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Paving: Products

Shale Interlocking Paver This paver has a wavy-surfaced stone texture. It is available with or without bevelled edges and appears more natural and rustic with ware.

Dimensions 200mm x 100mm Height 60mm/80mm Mass per Paver ¹ 2.6kg SANS 1058: 2012 Approved Pavers per m² 50 80mm available at PE branch only

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Bosun Bullnose This coping is designed for use on the edges of patios, pools, steps and staircases and therefore to ensure a slip-free surface it is manufactured with a shot blast texture.

Dimensions 300mm x 100mm Height 55mm Mass per Paver ¹3.6kg SANS 1058: 2012 Approved Pavers per m² 10 Not available at PE branch

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Kerbs


Kerbs

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Kerbs: Dry cast versus wet cast In Europe 95% of kerbs are manufactured using the Dry Cast method. In South Africa, as far as we are aware, Bosun is the only manufacturer of dry cast kerbs.

dry cast wet cast

Wet cast kerb (left) installed next to a dry cast kerb (right).

wet cast

dry cast

Two years later. Dry cast kerbs are darker. The surface doesn’t abrade as easily and better withstands acid attack in the long term.

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dry cast Dry cast kerbs are manufactured in the same way as interlocking pavers.

dry cast

wet cast Wet cast kerbs are manufactured in the same way as cobbles.

wet cast

Bosun dry cast kerbs were used on the left hand side of this traffic island. Wet cast kerbs were used on the right hand side.It is clear to see that the dry cast kerbs are dimensionally more accurate than the wet cast kerbs.

Reality check Kerbs are installed on roads. Expect them to discolour quickly due to tyre marks, exhaust fumes and asphalt. The production capacity of dry cast kerbs is not limited by availability of moulds.

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Kerbs: Innovation

Castle Bottom Kerb A

B

C

D

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Conventional Kerb


Castle Bottom Kerb A new innovation in kerbs, introducing the Bosun Castle Bottom Kerb, currently available in our 1000mm Figure 8C, Figure 3 and Figure 7 Kerb. The Castle Bottom Kerb has ribs or cavities across the bottom of its surface. Advantages of Castle Bottom Kerbs, compared to conventional kerbs: • The cavities provide a grip for installers when laying the kerbs, which allows for much easier handling. (Left Row A ) • The cavities make the Castle Bottom Kerb much quicker and easier to install. Where unlevelled screed surfaces forced installers to uplift, fill up and re-lay conventional kerbs it is easier to manoeuver a Castle Bottom Kerb into place, with the screed being displaced into the cavities in the kerb. (Left Rows B & C ) • Kerbs are laid on a concrete screed. Because the Castle Bottom has more point loads, it will therefore sink into the screed, providing much better adhesion IN ALL DIRECTIONS. The Castle Bottom eliminates air pockets in the screed beneath the kerb. Air pockets could create tensile weaknesses beneath the kerb when installed. (Left Row D ). Patent No. 2012\09544 Made in South Africa

Kerbs with nibs Bosun’s Figures 3 and 7 kerbs are available with nibs. Advantages of Kerbs with nibs compared to conventional kerbs: • The nibs ensure easier installation with the correct spacing between kerbs. • It reduces the likelihood of air pockets in the grout. • Because the nibs touch the adjacent kerb, it creates greater force stability which results in less movement when installed.

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Kerbs: Precast solutions p

Problem

s

Solution

Bosun Channel Kerb

p

Formworks with cast in-situ channels.

s

Bosun precast Channel kerb.

s

Bosun precast Edge beam with interlocking nib.

Interlocking Edge Beam

p

96

Cast in-situ Edge beams.


Transition Kerb

p

Cast in-situ Transitions to Mountable kerbs.

s

Bosun precast Transition kerb.

s

Bosun Delineator kerb.

Delineator Kerb

p

Back-to-back kerbs to create bus lanes.

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Kerbs: Installation and specification

The installation of kerbs is specified by SANS 1200MK. In principle, the following is prescribed: •

Trenches on which kerbs are to be installed should be excavated and well compacted. If the engineer finds that in-situ subsoil is not good, an imported sub base material should be used.

A bedding material of at least 50mm thick should be used that consists of crushed stone, cement, and sand with a maximum particle size of 13.2mm.

There should be close joints not larger than 10mm between kerbs and they should be filled with 3:1 sand / cement . The joints must be pointed. Ends of kerbs should be well moistened before jointing, and filled joints must be covered and kept moist for 48 hours. When joints have cured an appropriate sealant must be used where necessary.

Allow for expansion joints of at least 12mm at intervals of at least 20m.

After jointing, the kerbs must be backed with concrete “haunching” of at least 15Mpa and the space behind kerbs must be backfilled and well compacted in layers.

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SANS specifications for concrete kerbs explained The South African National Standard for precast concrete kerbs, edgings and channels SANS 927:2013: •

Bosun kerbs adhere to SANS specifications and are all manufactured according to the required specifications. Product guarantees are based on the same rules.

Kerbs are made up of high quality materials.

The kerbs will be free from cracks other than hairline cracks. They will also be free from visible twists and dents.

Kerbs dimensions stay within ±3mm of length and straightness.

Kerbs comply with strength specifications.

Kerbs are sampled and tested in a lab.

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Kerbs: Products

Figure 3 Kerb: Barrier Kerb Half-battered, heavy duty Barrier kerb. Used to create traffic islands and corners. It restricts access onto the pavement. Used in heavy traffic areas.

Length Mass Per Unit SANS

Fig 3 Long 1000mm ±110kg 927: 2007

Fig 3 Short 330mm ±36kg

Figure 4 Kerb: Barrier Kerb Half-battered, medium duty kerb. Installed in townhouse complexes and small shopping centres. It restricts vehiclular access onto pavements.

Length Mass Per Unit SANS

100

Fig 4 Long 1000mm ±80kg 927: 2007

Fig 4 Short 330mm ±26kg


Figure 7 Kerb: Semi-mountable Kerb The Figure 7 Semi-mountable kerb is used on public roads and other applications where limited access to a pavement is required.

Length Mass Per Unit SANS

Fig 7 Long 1000mm ± 105kg 927: 2007

Fig 7 Short 330mm ± 35kg

Transition Kerb (7/8C) This kerb serves as a neat and simple transition between Figure 7 and Figure 8C kerb. It is easy to install without the need for on-site curing.

Length Mass Per Unit

1000mm ± 120kg

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Kerbs: Products

Figure 8B Kerb: Medium-duty mountable Kerb A Medium-duty mountable kerb, ideal for use in residential estates and residential driveways on ramps.

Length Mass Per Unit SANS

Fig 8B Long 1000mm ± 86kg 927: 2007

Fig 8B Short 330mm ± 27kg SANS 927 : 2007

Figure 8C Kerb: Heavy-duty mountable Kerb A Heavy-duty mountable kerb for use on commercial and municipal road edgings where vehicular traffic needs access.

Length Mass Per Unit SANS

102

Fig 8C Long 1000mm ± 107kg 927: 2007

Fig 8C Short 330mm ± 36kg


Figure 12 Kerb: Garden Kerb Garden kerbs are ideal for neat and efficient edging of any paving. Well installed garden kerbs keep paving in tact and ensure that it doesn’t move. It can be used on residential and light duty commercial applications.

Length Mass Per Unit SANS

500mm ± 12kg 927 : 2007

Figure 14: Kerb Only available in Port Elizabeth. Channel for runoff water, used on commercial and industrial roads

Length Mass (1000mm length only) SANS

1000mm ±60kg 927: 2007

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Kerbs: Products

Edge Beam Commonly installed on paved areas with steep slopes in order to prevent horizontal creep and the subsequent opening of paving joints.

Length Width Height Mass Per Unit

1000mm 150mm 150mm Âą 55kg

Channel Kerb Channel Kerbs are used as a method of preventing the degradation of road surfaces and edging between channels and the kerb. Used as an edge restraint they carry the flow of water to the nearest catch pit.

Length Mass Per Unit

104

1000mm Âą 60kg


Delineator Kerb: Double-sided semi-mountable Kerb This kerb allows for buses to mount the kerb if necessary while smaller vehicles cannot. For use on bus lanes and BRT’s, shopping malls and parking bays. The Delineator kerbing system includes spacing blocks that allows for drainage.

Length Mass Per Unit

1000mm ± 115kg

Reality check Don’t expect kerbs to look like the smooth, shuttered concrete seen on buildings. Dry cast kerbs might initially appear to be darker than wet cast kerbs. In the construction of roadways, kerbs will take a beating from heavy machinery used in layer works. Contractors should be aware that kerbs are not unbreakable.

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Retaining walls


Retaining walls

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Retaining walls: Robust Block

Robust Block Bosun Robust Block Advantages 1 100% Consistent Block Heights A critical aspect with retaining wall blocks is consistency in block heights. SANS 508, (the official South African specification for retaining wall blocks) specifies dimensional differences of not more than ±3mm. The Bosun Robust Block guarantees these height tolerances or your money back. If there are any dimensional inaccuracies, it is at the back of the block that can’t be seen and it doesn’t have any structural influence. Why are block heights important to have blocks of consistent heights? The layer on top of irregular blocks will rock back and forth. n There will be uneven weight distribution of blocks placed on top of an uneven layer leading to stress points and ultimately block failure. n Geotextiles placed between uneven rows of blocks might tear or rip out. n It wastes a lot of time to level blocks on site with little stones etc. n

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2 Special V shaped stiffeners The Bosun Robust Block has a superior crushing strength compared to most standard concrete retaining blocks. The crushing strength is derived from various design elements including the unique V shape stiffeners in the block. Because of the superior crushing strength, the construction of retaining walls of 10m high is possible using the Bosun Robust Block. The V shaped stiffeners also offers a better distribution of force and in combination with the flat top of the block it offers better resistance to deflection on the sides and top of the block.

3 Flat Surface Because this block has a flat surface, vertical pressure from above is displaced more evenly and point loads are more spread than with conventional retaining blocks.

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Retaining walls: Robust Block

Robust Block Bosun Robust Block Advantages continued

4 Nib The Bosun Robust Block offers excellent horizontal shear (sliding from the back) resistance because of the specially designed nib.

*Other advantages of the nib are: n n n n

Less blocks are used in closed laying method. Gaps between the blocks are smaller in the open laying method. Less chance of soil falling through gaps in the open installation method. It is possible to build steep walls at angles of up to 80 degrees.

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5 0pen Blocks Soil erodes into the block at the back (open side) of the Robust Block. This means that soil doesn’t leave the retaining structure when it erodes.

6 Installation Guides The Robust Block offers installation guides on the top part of the block. These lines will ensure consistent overlapping of blocks on site.

7 Handling It is easy to pick up and handle on site. It is possible to carry six blocks with a gravity clamp.

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Retaining walls: Robust Block

Block usage in closed face laying pattern 9.09 Blocks / m² Block usage for open face laying pattern 5.13 Blocks / m²

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Dimensions Height Mass per Block

440mm x 300mm 250mm Âą47kg

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Retaining walls: Robust Block

Robust Block When the wall is packed using the nib, an 80° angle is naturally created.

There are two ways to create less steep walls: 1

Block layers could be moved back Loft required in degrees

2

Place upper block (x)mm back (layer by layer)

60°

144.3mm

65°

116.6mm

70°

91.0mm

75°

67.0mm

The foundation could be tilted in order not to lose the benefits of the nib.

Tilt measurement = foundation width (x) x tan O Foundation Width (x)

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Degree of wall required

O

Lower back of foundation by

400

75°

5

400

70°

10

70.5mm

500

75°

5

43.7mm

500

70°

10

88mm

600

75°

5

52mm

600

70°

10

35mm

105.7mm


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Retaining walls: Versoblock

Versoblock With its registered design, the Versoblock offers superb versatility. The lip helps to ensure that the blocks above keep their position behind the blocks below. • Versoblocks could be used with either the front, back or side exposed, to create different finishes. • Versoblock could be installed closed, creating a solid retaining feature – or open in order to create a living wall of plant life. • The load is carried on 5 points on the block compared to 3 points on similar systems – thereby increasing the stability of the wall. • Versoblocks are available with a lip which simplifies installation and increases stability.

Dimensions Height Mass per Unit

420mm x 300mm 200mm ± 28kg

Profile without lip Unit of measurement: mm

The load is carried on 5 points on the block compared to 3 points on similar systems. This increases the stability of the retaining wall.

Profile with lip

The lip helps to ensure that the blocks above keep their position behind the blocks below.

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Installation options Versatile in aesthetic appeal, Versoblock can be used with either the front, back or side of the block exposed to create different finishes. Side on

Front on

Back on

Versatile in strength, Versoblock can be installed in numerous ways to cater to the retaining wall’s strength requirements.

Side on open

Front on open

Back on open

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Retaining walls: Versoblock

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Reality check The strength of a wall comes from the design – not the blocks. It is therefore critical to consult an engineer when a wall is higher than 1.4m.

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Retaining walls: Installation guidelines Important aspects of retaining walls The strength of a wall comes from the design – not the blocks. It is therefore critical to consult an engineer when a wall is higher than 1.4m. Bear in mind that a retaining wall must resist the lateral pressures generated by the soils behind it or, in some cases water pressure too. Every retaining wall supports a “wedge” of soil. As the setback of the wall increases, the size of the sliding “wedge” is reduced. This reduction lowers the pressure on the retaining wall. The most important consideration in proper design and installation of retaining walls is to recognise and counteract the tendency of the retained soil to move downslope due to gravity. This creates lateral earth pressure behind the wall which depends on the angle of internal friction and the cohesive strength of the retained material. Lateral earth pressures are zero at the top of the wall and - in homogenous soil - increase proportionally to a maximum value at the lowest depth. Earth pressures will push the wall forward or overturn it if not properly designed. Also, any groundwater behind the wall that is not dissipated by a drainage system causes further hydrostatic pressure on the wall. It is critical to have proper drainage behind the wall in order to limit the pressure to the wall's design. Drainage materials will reduce or eliminate the hydrostatic pressure and improve the stability of the material behind the wall. When the weight of blocks alone is not enough to resist soil loads (walls higher than 1m), horizontal layers of geotextiles are used to reinforce soil behind walls. With proper soil reinforcement and design, retaining walls can be constructed to heights in excess of 20m. Why retaining walls fail: • Insufficient drainage • Incorrect or non-use of Geotextiles • Insufficient compaction of soil behind the wall • Inadequate foundations

Critical considerations • The NHBRC stipulation is that a wall of up to 1.4m doesn’t need an engineer’s approval if the soil is good compactible soil without excessive storm water and there is no load pressure on the wall such as vehicular traffic or buildings. Retaining walls which are higher than 1.4m need an engineer’s approval. • You cannot build a retaining wall where clay and non-compactible sand conditions exist. • For a wall which is higher than 3m the common rule is to use Geotextile in every third layer (we recommend that with a Bosun Robust Block that a Geotextile is used in every second layer). • Consider available space, drainage and water management.

Foundation All retaining walls should have a foundation, even if the wall isn’t high. • After excavating and digging the foundation the soil must be levelled and compacted. • Foundation dimensions are custom designed. • For walls which are more than 6 layers high, construct a concrete foundation. If walls are less than 6 layers high the soil needs to be compacted and cement can be added. • Wet your concrete foundation regularly for 24 hours for better curing and to prevent cracking.

Soil compaction • Inadequate soil compaction is the most common reason for retaining wall failures according to engineers. • The wall blocks are merely the ‘skin’. Compaction is what determines structural integrity. • Compaction needs to be done layer by layer behind the blocks. Lay one row of blocks and compact behind and inside the blocks using a mechanical compactor or roller and a hand tamper respectively before laying the next row. • Every layer must be moist when compacted (neither dry nor muddy). • Make sure to obtain the compaction density as per design. Normally 90-95% MOD ASSHTO.

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Packing • Make use of a string line or a dumpy level to pack straight walls. • Alleviate creeping on higher rows around corners by using half blocks when required. • Make sure blocks are level and not tilting or leaning in any way.

Use of Geotextile • Make sure Geotextile is laid smoothly and does not “concertina”. • The Geotextile is placed over a block and then the next block which is placed on top of it anchors it in place. • It is good practice to let the Geotextile protrude a few millimetres, making it visible. It is then cut off after completion of the wall. • Geotextile can be used as a base to prevent soil from falling through the blocks in the open laying patterns.

Drainage Good drainage is essential to prevent water build up. Without sufficient drainage, a dam is created. Always be on the lookout for excessive storm water drainage flow and if necessary build V-Drains 1.5-2.5 metres from the edge to channel surface water away from the retaining wall. • Drainage pipes must be laid in crushed stone and protected by Geotextile.

Design

Block height = 200mm

The most common measurement used by Civil Engineers to achieve the required construction angle is 75 degrees.

Degree 600 650 700 750 800 850

Technical specifications

Volume Length (mm) Height (mm) Blocks per m2 Weight per block (kgs) Minimum wall angle from horizontal Advantages Disadvantages

Tie Back (mm) 115.5 93.3 72.8 53.6 35.3 17.5

Side on closed orientation 0.012 420 200 13.09 28

Side on open orientation 0.012 600 200 8.33 28

Front & back on closed orientation 0.012 300 200 16.67 28

Front & back on open orientation 0.012 523 200 9.56 28

500

500

460

460

Easiest to install

Green wall

Green wall

Possible creeping around corners

Most economical material cost

Most aesthetically pleasing Most expensive material cost

Difficult to install

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Retaining walls: Installation guidelines

Good installation practices

122


Reality check The installation of retaining walls requires skill and meticulous attention to detail. The wall pictured above not only looks terrible, it is also likely to fail and when a retaining wall fails the consequences could be dire. It is critical to consult a specialised engineer and use a skilled contractor for the construction of retaining walls higher than 1.4m.

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Retaining walls: Design Concepts for Walls lower than 1.4m These Design Concepts are based on the Bosun Robust Block. For walls lower than 1.4m an engineer certificate is not required under normal conditions.

Normal conditions Normal conditions can be defined as: • The area must have good compactable soil (No sand or clay). • If the area does not have good compactable soil, fill material should be imported (G5 or G6 is acceptable). • No structural or vehicular loading. • No severe surface or ground water in the area. Foundation: • Excavate to a depth of ± 220mm. • Compact the soil 100mm below the intended concrete foundation to 93% MOD ASSHTO. • Construct a 400mm x 120mm, 20 Mpa concrete foundation - A concrete foundation will enable easier levelling. • The first block should preferably be placed 100mm below the ground level. Contruction: • Bosun recommends the wall to be constructed at a 75° angle. • After each block layer the soil should be compacted to 93% MOD ASSHTO. Do not compact layers more than 150mm thick. • Use a vibrating roller or jumping jack tamper for compaction. • Install 40/40 composite reinforcing geotextile between every second row of blocks. The geotextile should be ± 800mm from the front edge of the blocks. (Bosun recommends Rockgrid by Kaytech) • The geotextile should be laid evenly without creases. Bosun Versoblock installations, use a geotextile between every third block. • The most important aspect of Retaining Block Walls is the compaction behind the blocks. The Blocks act merely as the skin of the system.

Foundation detail

124


For areas with moderate surface or sub-surface water Normal condition definition must be considered. Foundation: • Excavate to a depth of ± 220mm. • Compact the soil 100mm below the intended concrete foundation to 93% MOD ASSHTO. • Construct a 400mm x 120mm, 20 Mpa concrete foundation - A concrete foundation will enable easier levelling. • The first block should preferably be placed 100mm below the ground level. Contruction: • Bosun recommends the wall to be constructed at a 75° angle. • After each block layer the soil should be compacted to 93% MOD ASSHTO. Do not compact layers more than 150mm thick. • Use a vibrating roller or jumping jack tamper for compaction. • Install 40/40 comosite reinforcing geotextile between every second row of blocks. The geotextile should be ± 1100mm from the front edge of the blocks. (Bosun recommends Rocgrid by Kaytech). • The geotextile should be laid evenly without creases. Bosun Versoblock installations, use a geotextile between every third block. • The most important aspect of Retaining Block Walls is the compaction behind the blocks. The Blocks act merely as the skin of the system. Subsoil drain: • The subsoil drain should preferably be installed ±600mm behind the blocks in order for water to flow into the drain opposed to the compacted area. • Use a 75mm perforated pipe, enclosed in 19mm or 6mm stone and wrapped in 150mm x 150mm A2 nonwoven filament geotextile (Bosun recommends Bidum by Kaytech). • Fines will clog the system if a geotextile is not used. • Construct outlets every 6 meters or dispose of water at the lowest end of the subsoil drain. V drain or kerb: • The purpose of the V drain is to direct water away from the Retaining Block Wall. • The V drain or kerb should be ±1.5m behind the top edge of the wall, in order to divert water from the compacted area.

Structural Drain Detail

* For more comprehensive details on design concepts or walls higher than 1.4m, refer to the website: www.bosun.co.za

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Retaining walls: Design Concepts for Walls lower than 1.4m Structural/ Vehicular loads for areas with sufficient space Load is at least 1.7m from edge of wall. Normal conditions definition must be considered. Foundation: • Excavate to a depth of ± 220mm. • Compact the soil 100mm below the intended concrete foundation to 93% MOD ASSHTO. • Construct a 400mm x 120mm, 20 Mpa concrete foundation - A concrete foundation will enable easier levelling. • The first block should preferably be placed 100mm below the ground level. Contruction: • Bosun recommends the wall to be constructed at a 75° angle. • After each block layer the soil should be compacted to 93% MOD ASSHTO. Do not compact layers more than 150mm thick. • Use a vibrating roller or jumping jack tamper for compaction. • Install 40/40 composite reinforcing geotextile between every second row of blocks. The geotextile should be ± 1100mm from the front edge of the blocks. (Bosun recommends Rockgrid by Kaytech) • The geotextile should be laid evenly without creases. Bosun Versoblock installations, use a geotextile between every third block. • The most important aspect of Retaining Block Walls is the compaction behind the blocks. The Blocks act merely as the skin of the system. Subsoil drain: • The subsoil drain should preferably be installed ±600mm behind the blocks in order for water to flow into the drain opposed to the compacted area. • Use a 75mm perforated pipe, enclosed in 19mm or 6mm stone and wrapped in 150mm x 150mm A2 nonwoven filament geotextile (Bosun recommends Bidum by Kaytech). • Fines will clog the system if a geotextile is not used. • Construct outlets every 6 meters or dispose of water at the lowest end of the subsoil drain. V drain or kerb: • The purpose of the V drain is to direct water away from the Retaining Block Wall. • The V drain or kerb should be ±1.5m behind the top edge of the wall, in order to divert water from the compacted area.

Foundation detail

126


Structural/ Vehicular loads for areas with limited space Loads should not be closer than 1m from the top edge of the Retaining Block Wall (Consult a Civil Engineer if the load is closer than 1m). Normal conditions definition must be considered Foundation: • Excavate to a depth of ± 250mm. • Compact the soil 100mm below the intended concrete foundation to 93% MOD ASSHTO. • Construct a 400mm x 150mm, 20 Mpa concrete foundation - A concrete foundation will enable easier levelling. • The first block should preferably be placed 100mm below the ground level. • Ref 193 Mesh or Y10 reinforcing can be added to the foundation depending on the load. Contruction: • Bosun recommends the wall to be constructed at a 75° angle. • After each block layer the soil should be compacted to 93% MOD ASSHTO. Do not compact layers more than 150mm thick. • Use a vibrating roller or jumping jack tamper for compaction. • Install 40/40 composite reinforcing geotextile between every second row of blocks. The geotextile should be ± 1200mm from the front edge of the blocks. (Bosun recommends Rockgrid by Kaytech). • The last geotextile layer must be laid under the load foundation ±1500mm from the top edge of the wall. • The geotextile should be laid evenly without creases. Bosun Versoblock installations, use a geotextile between every third block. • The most important aspect of Retaining Block Walls is the compaction behind the blocks. The Blocks act merely as the skin of the system. Subsoil drain: • The subsoil drain should preferably be installed ±600mm behind the blocks in order for water to flow into the drain opposed to the compacted area. • Use a 75mm perforated pipe, enclosed in 19mm or 6mm stone and wrapped in 150mm x 150mm A2 nonwoven filament geotextile (Bosun recommends Bidum by Kaytech). • Fines will clog the system if a geotextile is not used. • Construct outlets every 6 meters or dispose of water at the lowest end of the subsoil drain. V drain or kerb: • The purpose of the V drain is to direct water away from the Retaining Block Wall. • The V drain or kerb should be ±1.5m behind the top edge of the wall, in order to divert water from the compacted area. Foundation detail

* For more comprehensive details on design concepts or walls higher than 1.4m, refer to the website: www.bosun.co.za

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Information


Information

Things you should know about paving, prior to installation Delivery It is highly advisable for you and your installer to inspect our products upon delivery. In the unlikely event of either party disputing our contract of supply it remains the best time to resolve disputes with the least implications to all parties.

Installation It is always advisable to use an experienced and reputable paving installer. Obtain references beforehand and feel free to also contact Bosun in this regard.

Pricing Please consider pricing very carefully and bear in mind that there are always reasons why a product or a contractor might be comparatively cheaper. As a contractor, developer or home owner you will be spending a substantial amount of money on paving. Do your homework and bear in mind that the cost of an installation involves much more than the price which was initially quoted.

Maintenance Some claim that certain types of paving are maintenance free which is a myth. Although in many instances little maintenance is required, it is advised to at least replenish jointing sand by sweeping approved plaster sand over the paved surface from time to time. This costs very little but will go a long way to ensure a paving installation that lasts for many years.

Installation according to the South African National Standard It is imperative that your paving is installed in accordance with SANS 1200MJ. Even the most superior manufactured product might fail if the installation is not done in accordance to SANS. Amongst others, SANS 1200MJ specifies the quality of bedding and jointing sands and the method of installation. For more information on SANS 1200MJ, please refer to page 146. The Bosun 5 year guarantee is conditional upon installation being done in accordance with SANS 1200MJ.

How residential paving has traditionally been sold Traditionally concrete paving bricks or “cement bricks” have satisfied the price conscious segment of the market. Many paving contractors’ sales pitch sounds something like, “Clay bricks will cost you x amount. If you are looking for something a bit classier simulated stone or ‘SmartStone’ is an option but it is more expensive. However the cheapest option we can offer you is cement bricks.” However this has changed over the years. Modern manufacturing equipment and increased technical proficiency has allowed concrete paving manufacturers to produce unique products and remarkable finishes at the upper end of the scale.

129


Information: Paving material comparison

Paving Comparison Make an informed decision and know what you are buying. Contact www.bosun.co.za for a more comprehensive comparison. Below is a summarised comparison between the most common materials used for paving in South Africa. As advertised

Dry Cast Concrete (Bosun)

Wet Cast Concrete

Natural Stone

Clay

Tar

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What can be created

Possible outcome due to bad quality product, bad installation or limitations of the material used

Ageing


Most suited for: Residential driveways Pool surrounds Patios Internal tiling Landscaping Pathways Commercial parking Commercial driveways Public roads Industrial driveways

Dry Cast Concrete 3 3 3 3 3 3 3 3 3

Wet Cast Concrete 3 3 3 3 3 3 3 3

Natural Stone

Clay 3 3

3 3 3

Tar

3 3 3 3

3

3 3

In one word

Durability

Design

Natural

Clean

Road

Advantages:

Lowest cost of segmented materials. Dimensionally accurate and easy to install. Various shapes and sizes for a wide variety of applications. Durable.

An aesthetically pleasing alternative to brick. Re-creating the look of natural stone. Less damage to the environment than natural products. Various shapes, textures and sizes.

There is a positive, fashionable perception regarding the use of "Natural" products in building and construction. Natural stone can be beautiful.

Clay pavers have a natural appearance with very good colour fastness. Durable.

Low initial cost of installation. Smooth driving surface.

Be aware of:

Weathering of surface Obvious weathering of in the long term. surface in the long Some shapes of term. pavers are not "new" and exciting.

Lack of long term consistency. Limited dimensional accuracy.

Limited options in colours, shapes and sizes. Not modern and exciting.

Aesthetically, tar is limited. Not suited to low traffic areas or heavy vehicles turning sharply and slowly.

Most obvious possible post-installation imperfections inherent to the specific paving material:

Colour fading. Long term abrasion. White efflorescence. Black efflorescence.

Colour fading. Abrasion in the long term. White efflorescence. Black efflorescence.

Flaking or breaking. Staining and discolouration.

Spalling or chipping of Cracking and edges.Very susceptible potholes. Needs a lot to white efflorescence. of traffic to assist expansion and contraction.

Most obvious possible manufacturing defects (mostly applicable when purchasing from suppliers):

Products are dimensionally inaccurate. Uneven edges. Colour inconsistency. Not SABS compliant in terms of strength.

Dimensionally inaccurate products. Pin holes on surface. Not natural and sometimes irregular colours. Colour stains especially on larger products. Weak products.

Products are dimensionally inaccurate. Soft material. Stone that flakes or breaks. Colour inconsistency.

Weak product, breaking or crumbling. Chipped products. Products are dimensionally inaccurate.

Bad engineering or composition of material. Cracking.

Most obvious possible defects due to bad/faulty installation (mostly applicable when installed by an unqualified installer):

Complete site failure or pavers breaking and spalling due to earthworks. Unlevelled or irregular surface. Cement staining when installed with cement grouting.

Complete site failure or pavers breaking and spalling due to earthworks. Unlevelled or irregular surface. Cement staining when installed with cement grouting. Crooked installation lines. Failure of cement grouting.

Complete site failure or pavers breaking and spalling due to earthworks. Cement staining. Installation of chipped and irregular products. Crooked installation lines. Unlevelled or irregular surface. Failure of cement grouting.

Complete site failure or pavers breaking and spalling due to earthworks. Cement staining when installed with cement grouting. Crooked installation lines.

Site failure due to earthworks. As asphalt paving is "installed" in-situ, there are great risks involved when compared to other paving materials produced in controlled factory environments.

Aesthetics:

Limited larger paver options. Limited textures. Many colours available, but limited realistic, natural options.

Many shapes, sizes and unlimited textures. Includes large pavers. Combinations which may be installed together. Natural colours.

Mostly available in square, rectangular or totally irregular options. Limited textures. Natural colours.

Limited shapes and textures. Mostly available as standard "bricks". Limited colours.

N/A

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Information: Efflorescence

White Efflorescence Efflorescence is the formation of salt deposits, usually white, on or near the surface of concrete and clay bricks, causing a change in its appearance. Apart from the discolouration efflorescence is harmless. This is best described as being ‘a temporary skin problem and not a deep-seated disease’.

Efflorescence on Bosun Pavers In Gauteng efflorescence is most obvious in the rainy summer months, but may be observed throughout the year, especially in irrigated areas and after a sudden drop or rise in temperature. It can occur from within the concrete or from the subgrade (soil below the pavers). With time, efflorescence becomes less extensive and in most instances it disappears completely. Light coloured pavers might show the deposit less than darker coloured pavers.

How efflorescence occurs Efflorescence is a natural phenomenon that occurs through one or a combination of the following processes. Chemical processes Formation of efflorescence can be the result of a reaction of concrete constituents with carbon dioxide and/or sulphurous gases. Physical processes The formation of efflorescence could be caused by a number of physical processes involving both salt and water transfer in and out of the concrete product, the aggregates used in installation and the subgrade or earth beneath the pavers.

Removal of efflorescence • • • • • •

Efflorescence is very difficult but not impossible to remove. Irrespective of the method used to clean efflorescence, it could re-appear (in some instances more severely than before). In many instances rain will simply wash away white efflorescence. Some recommend dry brushing and the avoidance of water to clean effloresced pavers. Some recommend washing with clean water or a mild detergent. A proven yet risky method of cleaning efflorescence involves the application of a mild acid solution to the pavers. (One part pool acid with 12 parts water.) Thorough pre-soaking and post washing with clean water is required when using this method. Pre-soaking reduces natural porous tendencies, limiting the depth of penetration of the cleaning solution. Post-washing is required to remove any residue of the acid.

Bosun’s take on efflorescence • Efflorescence is a natural phenomenon appearing randomly in most materials used for segmented paving. As mentioned earlier it could even be caused by the earth on which the paving is laid. Bosun Brick and other companies are actively working to find a remedy for efflorescence. • Many paving installations have never been affected by efflorescence. Some have had efflorescence for a few weeks while others have been affected for months. Sometimes efflorescence is recurring and sometimes it happens only once. • Bosun Brick cannot guarantee efflorescence-free products. (Prior to- or post-installation.) Bosun Brick’s comprehensive Five Year Guarantee therefore does not cover efflorescence. Remember, White Efflorescence is usually a temporary problem.

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Black Efflorescence

(Desert varnish or Black attack)

lBlack Efflorescence is the unpredictable sporadic darkening of concrete, clay and natural stone. It usually occurs within six months of installation and is not easily removed either with solvents or by physical means. This phenomenon is all around us. It might occur on pavers, bridges and buildings. Many studies have been conducted and the precise cause of this phenomenon is still not well understood. It has been found however that there does seem to be a correlation between black efflorescence and the moisture of the installed area. In the short term the only solution is to replace the affected pavers and ensure adequate drainage of the sub base during installation. Over time and as the pavers wear the discoloration might fade and blending with other pavers will improve. There are other kinds of discoloration that could be mistaken for black efflorescence namely: Mold, algae, tyre rubber and staining from bedding sand. White efflorescence

The same site 6 months later

Black efflorescence

Reality check The formation of efflorescence on a site (black and white) is linked to the earth’s water content beneath the paving. In areas where high water tables exist or where moist clay soils are prevalent, efflorescence is usually a common occurrence . Black efflorescence is usually common to specific geographical areas. A neighbour’s paving and adjacent concrete structures would give you an indication of the potential of your paving being affected by efflorescence.

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Information: Selecting the right contractor For structural soundness a paving installer should be asked questions based on the following in order to determine the likelihood of installations lasting for many years. CATEGORIES OF CONTRACTORS

A Bulk earthworks to be carried out in compliance with specification (compaction to be done by means of at least a vibrating roller): Layer works designed by an engineer: Imported sub base(s) material and compaction to specification:

Sub base stabilisation to specification:

B

X

C Although Bosun doesn’t recommend the use of a plate compactor for earthworks, when being used it should be one of at least 150kg.

X

D Making use of hand stampers and small plate compactors, or even no compaction whatsoever.

Will increase cost.

This

X

X X

X Bosun doesn’t recommend installing paving without an imported sub base. If not, at least ensure that the natural earth is of good quality and properly compacted when moist. Reputable contactors will always discuss soil conditions

or X Although Bosun strongly recommends stabilisation, at least discuss it with the contractor. If he doesn’t know what it is, don’t use him.

X

X

“I’ve been in this game for xx years. I know what I’m doing.” No consideration of soil conditions.

“Huh?”

This will however cost more.

Engineered drainage plan: Durable edge restraints:

or X A better contractor will discuss the drainage plan in detail. or X A good contractor would describe various options in detail. If he wants to do troweled edges in situ, don’t use him. Durable edge restraints will be more expensive.

Correct Bedding according to specification:

or X Better contractors will use moist, good quality, washed river sand, which is at least 25mm thick when screeded. Quality bedding material will be more expensive.

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X X

X

“We’ll determine it while we’re installing. I’ve been in this game for xx years.” Troweled concrete edges will fail within a year.

The use of too little and the wrong type of bedding material is very common. This will cause site failure.


A paving installer should be asked questions based on the following in order to determine the likelihoood of an aesthetically pleasing installation. CATEGORIES OF CONTRACTORS

A Handling pavers with care:

B

or X

C Bosun recommends the use of paving carts or at least making sure that wheel barrow tipping is not allowed. Careful handling will be more time consuming and therefore more expensive.

Precision cutting of pavers:

or X Bosun recommends the use of block cutters or at the very least an angle grinder with a diamond tipped blade. Will increase cost.

Levelling of pavers with rubber mallets or a plate compactor prior to grouting:

or X At least ensure that compaction (levelling) is done prior to grouting and again shaking sand into joints when grouting. More time consuming therefore more expensive.

Checking and adjusting lines and pavers: Correct grouting with the correct, dry sand:

Competent Supervision on site:

Cheap blades and bolsters give a rough finish.

X

“Hiring a plate compactor is expensive.”

X

or X Most residential contractors will use wet cement grouting. Although Bosun doesn’t recommend it, at least ensure that the contractor has a method of combating cement staining

X

It is time consuming and time is money.

or X This is one of the reasons why contractors use cement grouting although it is contrary to the principles of segmented block paving. or X

Will increase cost. Proper supervision costs money.

Careless handling of pavers such as throwing and dumping will damage and scuff them.

X

or X A better contractor will do this.

Will increase cost.

Re-grouting in 7 days and again in 3 months:

X

D

Paving lines and the paved surface will be crooked and uneven. Paving will be stained and the installation a disaster if grouting isn’t done properly.

X

“In xx years I haven’t had any problems with grouting.”

X

ìI supervise my six teams personally.”

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Information: Selecting the right contractor A paving installer should be asked questions based on the following in order to determine whether dealing with him will be a good experience. CATEGORIES OF CONTRACTORS

A

B

Prompt rubble removal: Answering his phone, even after installation:

Will take responsibility when things go wrong: X

X

Requires large deposit:

X

or X Ensure the contractor has a landline number and legitimate physical address. Cellphone calls can easily be avoided.

X

or X Ensure that the contractor belongs to an industry body like the CMA or MBA, who can intervene when necessary.

X

or X If the contractor wants more than 50% upfront, you are at risk. X

X

Will increase cost.

X

or X How is it possible without a physical address or office? This costs money. or X As with contractors there are also reasons why one supplier might be more expensive than another. Quality costs more.

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X

D “My truck broke down. It should be fixed by next week.” “Hi. This is Jo Bloggs from Jo’s paving. Please leave your name and number and I’ll get back to you as soon as possible.” “Hi. This is Jo Bloggs from Jo’s paving. Please leave your name and number and I’ll get back to you as soon as possible.”

Membership fees are payable to industry bodies.

or X Better contractors have workers with clearly identifiable industrial clothing.

Cleanliness and professionalism:

Will try to swing quality pavers to a cheaper product from an unreliable supplier:

or X Always ask if it is included in the quote.

or X Better contractors will always discuss facilities prior to installation.

Toilet on site:

Have good admin and systems:

C

X

“The bricks are the most expensive item and I have to pay cash upfront for them.” “My guys don’t generally need a toilet.” They’ll just wear what they wore when the “contractor” picked them up at the hardware store’s gate. “If you pay cash, I won’t charge you VAT.” “All bricks are the same. These cost less because the manufacturer doesn’t advertise.”


Summary CATEGORIES OF CONTRACTORS

LIFE EXPECTANCY OF PAVING:

PRICE OF INSTALLATION:

MAKE THE RIGHT CHOICE:

A

B

C

D

Commercial paving is guaranteed to last a lifetime.

Residential paving is guaranteed to last a lifetime.

Paving will last but sagging, ponding and edge failures might appear very early on if any of the above aspects are not adhered to.

Paving will fail.

MOST EXPENSIVE Engineers are expensive but their responsibility is extensive regarding the supervision of construction and evaluation of site conditions.

SECOND MOST EXPENSIVE It costs money to create good infrastructure.

A CHEAPER OPTION Generally these contractors walk a fine line in order to be price competitive.

CHEAPEST OPTION Naturally they’ll be the “cheapest”.

Contractors who comply with international standards of installation. COMMERCIAL PAVING

Contractors who comply with international standards of installation. RESIDENTIAL PAVING

Common practice by South African contractors.

Opportunistic contractors.

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Information: Laying patterns

Bevel Bond, Urban Small & Urban Slimline

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Bosun Cobble, Split Bevel Bond & Rio Rocosso Bevel

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Information: Laying patterns

Interlocking Pavers

Citylock

Permeable Citylock

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Smooth Ethnic, Urban Medium & Urban Large

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Information: Laying patterns

Urban Range Combination Patterns

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Urban Range Combination Patterns

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Information: Laying patterns

Waterwise

Paver layout Permeability Quantity

20% closed 20% 25 Pavers per m2

Paver layout Permeability Quantity

60% closed 4.2% 28 Pavers per m2

Paver layout Permeability Quantity

40% closed 15.7% 23 Pavers per m2

Paver layout Permeability Quantity

100% closed 0.2% 30 Pavers per m2

Paver layout Permeability Quantity

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80% closed 3.4% 28 Pavers per m2


Venetian Paver

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Information: Laying patterns

Linneo Paver

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Information: Installation guidelines These guidelines are based on SANS 1200MJ, the official South African specification for the installation of paving. Important: Earthworks (base layer preparation) are site specific and fall within the scope of an engineer’s expertise. Bosun strongly advises that an engineer should design any paving’s earthworks. This is imperative for commercial, public and industrial sites intended to carry heavy vehicular traffic.

Terminology: • Sub grade is the natural earth on which paving will be installed that is to be prepared. • Sub base is the prepared layer beneath the paving and bedding sand. (In South Africa it is usually “natural earth” unless otherwise specified by an engineer. In other countries it is usually a special imported material, consisting of particle sizes between 40mm and dust). • Bedding sand is the final layer upon which the paving blocks are installed. • Jointing sand is used for grouting between pavers. • Earthworks or base preparation (Beneath the bedding sand) • The soil conditions and application will determine whether a special sub base is required. An engineer is required to calculate the need and specification. This will involve excavation and back filling. • For domestic driveways and paving subjected only to pedestrian traffic, good quality natural earth might provide sufficient strength for the installation of paving. (However, If you want your paving to last for a lifetime, insist on an imported sub base.) Sandy and clay soil conditions will always require a specially designed sub base.

Compaction • Good compaction of the sub grade and sub base is critical for your paving installation to last, whether you use an imported sub base or not. Good compaction means compaction in layers and not merely the compaction of the top soil. In practice it means that you have to take out soil, compact, put some soil back, compact, etc. • Hand stampers and small plate compactors are simply not good enough to achieve proper compaction. We recommend the use of a mechanical roller to achieve good compaction.

Bear in mind that: • Excavation is usually required on areas intended for paving. The extent of excavation is determined by the thickness of pavers to be used together with their bedding. • In most instances, excavated material will need to be removed from site. • There might be natural depressions in the earth of the area to be paved and depending on the degree of the depressions special materials will be required to fill them. On residential driveways excavated earth will usually be usable. Bedding sand should not, under any circumstances, be used for this purpose. • All plant material and roots must be removed from the soil and site. • Carefully consider the roots of trees that might eventually grow under paving. • Carefully consider underground utilities prior to excavation and digging. • After excavation, “drainage levels” have to be checked and rectified.

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Drainage • Many paving failures are due to ingress of water into the earthworks beneath the paving. In order to eliminate this problem pay attention to drainage. • It is necessary that there are adequate longitudinal falls and no undulations to prevent ponding and infiltration of water into the layer works, particularly in the first year after installation. A minimum fall of 2% in any direction is generally required. It is also important to ensure that the paving is laid proud of (i.e. 5-10mm higher than) storm water structures or channels. • Where a high water table exists, subsoil drainage should be installed. • Drainage channels and underground drainage pipes should be installed in certain areas like low points in steep driveways, around downpipes etc. • Consider the natural land and buildings when designing a drainage plan.

Subbase stabilisation Subbase stabilisation should be done in accordance with SANS 1200MJ when specified. In simple language this requires cement to be mixed into the subbase.

Edge restraints • The earth preparation should extend to the rear face (back edge) of edge restraints. • Edge restraints consisting of kerbs or channels must be constructed on the sub base before paving is laid. In residential applications, an edge restraint might be constructed by laying the pavers on the edge in a concrete bed. (This is often called the header course.) • Experience has shown that the best edge restraints are kerbs. For residential and pedestrian applications, garden kerbs are perfect. There are many aesthetically pleasing options on the market. • On large paved areas and paving on steep slopes, additional restraints in the form of edge beams might be required. Please refer to the CMA manual for paving on steep slopes. • In situ concrete on edges is not recommended as it usually breaks after a few months.

Bedding sand • The incorrect selection and application of bedding sand is a major cause of site failures. • The sieve analysis of bedding material is specified in SANS 1200 MJ. (The only South African specification for the installation of concrete paving.) To simplify what is said in SANS 1200MJ, good quality, washed river sand usually falls within this sieve analysis and is therefore recommended as default bedding material. • Cheap, inferior bedding materials will cause site failure. • Do not mix cement with bedding sand, unless specified by an engineer.

Bedding sand, dos and don’ts: • Bedding sand must be spread over the subbase and evenly screeded in the loose condition so as to achieve an even thickness of 20-30mm. • For pavers larger than 250mm on one edge we recommend a thickness of 40mm of bedding sand. • Do not compact bedding sand before laying pavers. • Where the sand bed is accidentally compacted before the units are laid, it must be raked and evenly re-screeded in a loose condition. Continued on Page 150

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Information: Installation guidelines Bedding sand, dos and don’ts continued: • Bedding sand must be moist. (Not saturated with water, only moist) • The sand bed must be laid slightly in advance of the placement of the units but only to the extent that the particular area of paving can be completed on the same day. (With the sun baking down, it might be limited to a few hours at a time.) Therefore the moisture content of bedding sand should be continuously assessed on site. • Where bedding sand dries out, it must be raked back into a heap, moistened with water and shovelled in order to obtain consistent moisture. Only then must it be levelled out and screeded again. • Do not add water to spread out bedding sand. • Dried out or too little bedding sand will cause: - Uneven paved surface. - Rocking pavers that will break in time. - Grouting failures. - Pavers with chipped edges (Spalling). - Do not use plastic sheeting beneath or on top of bedding sand. It doesn’t stop weeds from growing and badly affects the structural integrity of the paving.

Laying of pavers • Where appropriate, lines must be set up at right angles to each other to control the alignment of the pavers. • Joint widths must be between 2mm and 6mm. • Nibs on pavers are generally between 1mm and 2mm in size. This is smaller than the joint widths as specified by SANS 1200MJ. The ideal would therefore be to use nylon line as guides and leave grouting gaps larger than the paver nibs. • In other countries, it is specified that nibs be used as a guide only and that pavers should be packed without touching at all. • In practice in South Africa concrete pavers are always butt jointed with nibs touching adjacent pavers. Technically this is not correct but in reality only artisans can do this and there are very few paving artisans in South Africa. • Pavers from various packs should be mixed when installed. Installing pack by pack will lead to a “patchy” finish. • Pavers should be transported in a paving cart or wheelbarrow prepared with blankets. They should not be thrown into wheelbarrows or front end loaders and dumped. This will damage the pavers.

Cutting • Whole units must be laid first. Precisely cut pieces should then be fitted into gaps which are too small to lay complete pavers in, such as those which are close to edges and around manholes. • The best practice is to mark pavers when they are packed out and then to individually cut them with a special paver cutter or masonry saw with a diamond tipped blade. In reality though pavers are in many instances packed out, marked and cut with an angle grinder on the ground. When this procedure is followed, cutting will never be as accurate and as neat as required.

Levelling (First compaction of pavers) • Compaction of pavers should be done while the bedding sand is still moist. It is a useless exercise on dry bedding sand. • All debris and sand should be cleaned off paving prior to plate compaction. • For the Bosun unbevelled Large Urban Pavers we recommend that compaction should only take place after jointing sand has been swept into gaps between pavers. This will help to prevent edges chipping. In this instance, initial levelling should be done with a large rubber mallet which is available from Bosun. • For any other pavers with bevelled edges we recommend that at least two compaction passes with a mechanical plate compactor should be made over the paving as soon as possible after laying, and before the introduction of any jointing sand. • By the end of each day compaction must be completed to not closer than 1m from any free edge. A uniform even surface should be obtained over the paved area. • To avoid damaging pavers we recommend fixing conveyor belting onto the vibrating plate of the compactor.

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• After compaction, lines should be checked and adjusted with a crowbar or special alignment tool. If necessary these areas should then be re-compacted. • Temporary edge restraints should be used across the front laying edge when installations are to be continued on the next day.

Joint filling and second compaction of pavers • The joints should not be filled until all cut pieces of paving have been inserted, all the necessary adjustments to the line and level have been made and the pavement has been subjected to at least two passes of the compactor. • Sand that complies with sieve analysis as specified by SANS 1200MJ must be used as jointing sand. In South Africa, plaster sand is usually close to the specified sieve analysis. • Avoid the use of red plaster sand for grouting. It will stain your paving. Always use light coloured plaster sand for grouting. • In other countries, silica sand is used as jointing material and is definitely the better option. (It is however more difficult to acquire and subsequently a more expensive option). • The most important aspect of jointing sand is that it has to be bone dry. (Moist jointing sand will not fill gaps between pavers consistently and will cause “bridges” that will collapse in time).. • Jointing sand should be broomed into the joints until they are filled and sufficient passes of a plate compactor should be made to settle the joint filling. (The jointing sand should literally be “shaken” into the joints by the plate compactor). • The procedure shall be repeated until the joints remain full after compaction. • On completion of compaction all excess sand shall be broomed off and disposed of. Damage caused during compaction shall be compensated for by the contractor at his own expense.

Most importantly: • It is critical to sweep more sand into paving joints a week after the initial grouting. Grouting sand will in many cases settle and subsequently leave “groutless” gaps between pavers. It isn’t even necessary to use a plate compactor for this exercise. • Grouting sand should again be swept between pavers after six months of installation or after the first heavy rains. This will fill joints and create good interlocking between pavers. If this is not done, there will be a chain reaction of grouting eroding and being washed out and eventually pavers will be totally loose, spelling site failure.

Cement grouting In our opinion and according to SANS 1200MJ, cement should not be added to jointing sand. However, in South Africa it is common practice to grout paving with a cement slurry rather than sand. This defies the principles of segmented block paving as you create a solid “slab”. Cement grouting minimises certain risks and effectively “hides” certain possible problems. Generally, most residential paving installations are done with cement grouting and because it carries light traffic it generally works.

Where cement should be added to sand grouting: When paving on steep slopes. Around down pipes. Along roof overhangs with no gutters.

Alternatives to cement grouting There are specialised grouting options which will work out to be more expensive than cement, but that offer much more in terms of reliability and longevity.

Using the paving Sand grouted paving could be used by vehicles immediately after grouting. Cement grouted paving should not be used for 7 – 10 days after installation.

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Information: Installation guidelines

Installation guidelines for Large Pavers The installation of large pavers is also based on the guidelines on the previous pages. The only real differences are: • Urban pavers are larger than normal paving bricks and they are more difficult to level. Thicker bedding sand, a thickness of around 40mm, will accomplish easier and better levelling as opposed to installing smaller pavers on a bedding layer of 20-30mm. • Large pavers are levelled by means of large rubber mallets called “mauls”, rather than plate compactors. A plate compactor should however still be used when grouting. • Sand grouting specified for large paving slabs in countries with more experience in their installation is washed, kiln dried silica sand with particle sizes between 1mm and dust. 40kg bags of this grouting sand is available from Bosun. Reality check It is more difficult and costs more to install large pavers, compared to standard sized pavers and interlocking shaped bricks. If your installer charges the same price as for small pavers, you could almost certainly expect problems on site.

A practical example of poor installation This small walkway was installed a year before these pictures were taken. • No compaction was done. • No proper edge restraints were created. • Plastic sheeting was installed under the paving. • Bricks were not from a SABS approved supplier.

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Although this path carries only light pedestrian traffic: • A section has started to collapse a few months after installation. • Edge restraints are breaking and paving on the edges will soon start to move apart. • Weeds are still growing. So much for the plastic sheeting.


Information: Waterwise paving installation guidelines

Guidelines for successful functional and structural performance of Bosun Waterwise Pavers Please Note: This document is merely a guideline for the installation of the Bosun Waterwise paver. Individual analysis and design of a specific site would have to be conducted by a qualified engineer. Bosun could be contacted in order to provide the services of a contracted industry expert in this field in order to assist engineers for a nominal fee. The Bosun Waterwise paver brings a new dimension to aesthetic appeal and drainage capability of large areas used by pedestrian or vehicular traffic. Successful use is however dependent on proper design and installation. These guidelines assist practitioners in specifying and applying sound procedures. They are focused on specific requirements and are supplemental to general industry documents such as the Concrete Manufacturers Association (CMA) “An introduction to permeable concrete blocks”.

Managing water runoff Managing water runoff is a current environmental focus, as it manages surface water by attenuation and filtration with the aim of replicating, as closely as possible, the natural drainage from a site before development. Managing water runoff consists of: • minimize water runoff QUANTITY; • improve water QUALITY; and • provide AMENITY and biodiversity through an improvement of the environment. There are three permeable concrete block pavement (PCBP) systems, which are commonly known as Systems A, B and C. The systems possess different drainage attributes, but visually look the same. System A – full infiltration This system is suitable for existing soil (subgrade) conditions with good permeability, and allows all the water falling onto the surface to infiltrate through the constructed layers to the water table, as shown in Figure 1. No water is discharged into conventional drainage systems, eliminating the need for pipes. This system is only suitable if the subgrade can accept the water without complications.

Figure 1. System A – full infiltration.

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Information: Waterwise paving installation guidelines

Guidelines for successful functional and structural performance of Bosun Waterwise Pavers continued System B – partial infiltration This system is used where the existing soil (subgrade) is unable to absorb all the water that falls on the surface. Surplus water is then removed by a pipe drainage system in the pavement structure, as shown in Figure 2. By the attenuation achieved in the permeable subbase, runoff, and thus the danger of flooding, is significantly reduced.

Figure 2. System B – partial infiltration.

System C – No infiltration Where the existing soil (subgrade) is poor or contains pollutants, System C allows for the complete capture of all the rainfall, as shown in Figure 3. The porous nature of the subbase functions as a storage tank, reducing peak flows through the outlet pipes leading to other surface drainage systems such as ponds or water courses.

Figure 3. System C – no infiltration

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Design requirements Lower membrane In Systems A and B the lower membrane should be a permeable geotextile, to allow water infiltration. This membrane should have the required strength not to be damaged when the stone for the subbase is placed, and it should remain permeable (not clogged) during the life of the facility. In System C the lower membrane is impermeable, being capable of being welded to ensure a complete seal, and strong enough not to be damaged (holes punched) when the porous subbase is constructed.

Subbase thickness requirements The permeable subbase consists of a 26.5mm or 19mm single sized crushed stone. This type of stone has about 40% of the volume as air voids, which means that 40% of the layer volume can be filled with water. If the layer is 150mm thick, it can accommodate 60mm of rainfall in the layer if there is no infiltration or outflow. This is sufficient for most rainfall events. In cases where more substantial requirements must be provided, advanced analysis techniques are available, and BOSUN is able to provide a service to assist designers. (We utilise the services of an academic in this field. The costs and timeframes of consultation would be determined by this individual.) From a structural perspective, a 150mm permeable subbase is sufficient to carry 1 million standard 80 kN axles during the life of the facility (about 25 trucks per day) on a subgrade with a CBR of at least 15. This is adequate for most applications in the urban environment, such as access streets, parking areas, hardstands around office and residential properties. For large projects or facilities carrying large numbers of heavy vehicles where the implications of inadequate structural design are significant, detailed mechanistic design can be performed by specialist pavement engineers. BOSUN offers a service to assist with the structural design or review designs as mentioned above.

Construction of permeable subbase and bedding layer(s) On Figures 1 to 3 a permeable geotextile membrane is shown as separator between the coarse stone and the bedding layer. From a functional perspective a membrane is a feasible solution, but in practice this invariably causes problems. Before the membrane is placed, particle interlock of the coarse aggregate must be achieved by using a heavy roller with a mass of at least 8-ton and preferably with vibrating capability. A 1-ton walk behind roller does not achieve particle interlock. The area to be paved has to be completed so that the membrane can be placed (this is sometimes difficult to achieve on a small site). After construction of the paving, if trenching has to be done the membrane is invariably pulled up and not reinstated after trenching is complete. An alternative to using a geotextile membrane, yet preventing the bedding sand from disappearing into the coarse stone layer, would be to select progressively finer materials. These materials are selected using the well-known filter criteria, as is explained next. The two aggregate materials should meet the following criteria: D15 subbase D85 bedding layer must be less than or equal to 5. where Dx is the particle size at which x% are finer. Using the example in Figure 4, D15 subbase is the size where 15% of the subbase is finer, namely 8mm, and D85 bedding layer is the size where 85% is finer, namely 3.7mm. The ratio of 8/3.7 is 2.16, which is less than 5 and thus satisfactory. It is advisable to check visually on site that the laying course particles fit into the voids of the sub-base material without excessive migration into the sub-base.

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Information: Waterwise paving installation guidelines

Design requirements continued The bedding layer should have a thickness of 20mm to ensure that undue deformation does not take place, but adequate drainage occurs. The bedding layer is spread after complete compaction of the subbase with a heavy roller to achieve full particle interlock. Compaction of the bedding layer is by means of a plate vibrator on the paving blocks.

Figure 4. Example grading characteristics of permeable subbase (blue) and bedding layer (yellow).

Jointing material The role of the jointing material is to ensure drainage through the joints in the paving blocks, and to achieve “lock-up” in the paving system. “Lock-up” is when the paving blocks function as a unity and not individual blocks, and provide structural strength. By vibrating the dry jointing material into the joints load transfer between blocks is achieved. The joints in WATERWISE permeable pavers are 3-5mm in width. The maximum size jointing material can thus be no larger than 2mm, as a rule of thumb suggests the maximum size to be two-thirds of the joint spacing. The jointing material should have no fine material passing the 0.425mm sieve. In the large squares of the WATERWISE permeable paver a 6.7mm single size stone can initially be placed to improve permeability before the jointing sand is added. The suggested materials fulfill the filter criteria and will not wash into the subbase. Should the WATERWISE paver be used for aesthetic purposes and not for its drainage capability in a standard pavement, conventional jointing sand should be used to try and make the system impermeable.

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Information: Common paving installation problems Most paving installation problems have a snowball effect where one problem will lead to another, which might cause yet another problem, which will ultimately result in complete, irreparable failure of a paved area.

EARTHWORKS

EDGE RESTRAINTS

LEVELLING

Paving problems are mainly caused by inferior earthworks. When a paving site’s sub base has failed due to incorrect earthworks the result will be disastrous and irreparable.

Inadequate or inferior edge restraints will lead to movement and subsequent loss of jointing sand.

Uneven paving is unsightly and dangerous to walk on.

COMPACTION

BEDDING SAND

JOINTING SAND

Inadequate compaction of sub base will cause pavers to sag which will result in water ponding as discussed below.

Inferior or insufficient bedding sand might cause pavers to move and break.

When jointing fails, pavers will move and edges will chip or break. It might also lead to other problems as discussed previously.

DRAINAGE

CAREFUL HANDLING

CEMENT STAINING

Incorrect drainage will cause ponding and water will infiltrate the sub base which will cause it to fail.

Careless and indiscriminate handling of paving will cause chipping and breaking.

Cement grouting can cause permanent stains on paving when the grouting is not correctly cleaned off the pavers.

CUTTING

ATTENTION TO DETAIL

SKILLED ARTISANS

Good cutting will create a beautiful effect, but bad cutting will look awful.

If paved lines aren’t straightened and broken pavers not removed it might lead to further problems.

It is a skill to install finishing touches and little things could ruin an otherwise good installation.

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Information: Maintenance

Maintenance of Bosun Dry Cast Concrete Pavers Regular maintenance and good cleaning practices will enhance the overall appearance of your paving.

General Cleaning of Paving Regular hosing and sweeping with a hard bristled outdoor broom will not only keep your paving looking clean but it will also prevent weeds from taking root as they usually grow where seeds are left undisturbed to germinate in the debris that collects between the pavers. When the paving is heavily soiled use a general purpose pH neutral/slightly alkaline, non-abrasive cleaner. Make sure all the soap has been thoroughly removed from the surface after cleaning and that the run-off of soapy water is channelled to drainage points or containers where it can be disposed of safely. Note: Do not use power hoses to clean paving as this may wash out jointing sand and damage the grouting between pavers and will damage the pavers themselves.

Detergents Bosun recommends specialised products like Tile and Floor Care. www.tfc.co.za It is essential to seek expert advice and guidance. Bosun cannot accept any responsibility for inappropriate use and application of detergents.

Mechanical cleaners It is advised that sections of paving, at least, be cleaned daily at commercial pedestrian areas like shopping centre piazzas and walkways. We recommend the use of specialised equipment for daily maintenance of large paved areas. Tennant cleaning equipment is a respected option. It is strongly advised that an industry expert advise you on equipment to be used on your site. Bosun can’t be held responsible for the use of the wrong cleaning equipment.

The following recommendations deal with sweeping machines and associated equipment and their use: • Equipment should be custom designed for sweeping a particular area. If there is any doubt the equipment manufacturer should be consulted. • Tyres should be inflated according to the manufacturer’s recommendations to ensure maximum weight distribution. • Polypropylene, not wire brushes should be used. • The brush pressure of the sweepers should be set to the minimum requirement for the particular task, i.e. surfaces swept regularly will require a lower setting than those swept infrequently or those covered with heavy deposits. • When sweeping, engine revolutions should be set to the minimum requirement to maintain vacuum (suction) pressure. • Operators, including temporary staff, should be trained according to the vehicle manufacturer’s recommendations. Tyre and brush pressures should be checked regularly. • Operators should be advised to switch off suction, brush rotation and water jetting equipment when machinery is stationary or left unattended, to avoid the risk of damage to the area underneath the equipment. • In new or re-laid areas, allowance must be made for the pavement to settle and the joints to seal before cleaning manually. • When using water jetting equipment to wash such areas, the jet or hand held lance should be directed diagonally at the surface (i.e. not parallel to joints), at a 30° angle, not greater, using a suitable detergent solution. • The area should be inspected after cleaning to refill joints with jointing sand if necessary.

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Stain removal & Spot Treatments Oil stains: As soon as the stain appears dab excess spillage with an absorbent cloth or towel. Then remove the stain with soap, water and a brush. Ensure that all residues are washed away with hot water. Scuff marks from vehicle tyres: These marks can normally be removed by scrubbing the area with hot water and a strong detergent. Remember to rinse thoroughly. Rust stains, concrete, plaster and paint marks: Call in a cleaning professional to assist with the cleaning of these particular marks on your paving. Beverage, smoke, fire and tobacco stains:  These can normally be removed by scrubbing with hot soapy water. If the stain is persistent, apply a mild bleach solution and then rinse the area with clean water, taking care to dispose of the run-off safely.

Weeds It is a common misconception that weeds grow from underneath paving. This may occur on rare occasions but weeds almost always grow from seeds and bird droppings that land in the paving joints. Regular hosing and sweeping of the paved area will prevent weeds from growing as it disturbs newly emerging weeds before they are able to become fully established.

Maintenance tips Inspect paving on a quarterly basis: Inspection is done to check for any loose, damaged or stained paving, and to ensure that the jointing material is intact. Loose paving: It is important to rectify the cause of the paving’s movement. Subsiding of the substrate layers is the most common cause of pavement failure. No matter what the cause, it needs to be investigated and rectified before replacing or re-bedding the pavers. Damaged or stained paving: Individual blocks can easily be replaced. Refer to the Bosun website for further information on how to re-lay damaged paving. Jointing material that is no longer intact:  The pavers simply need to be topped with jointing sand by brushing or sweeping in approved dry plaster sand where necessary.

Maintaining paving during construction Paving should be kept covered during construction or renovation for protection from damage and possible staining from paint or oil-based substances as well as any harsh chemicals.

Sealing of block paving Bosun recommends Tile and Floor Care. www.tfc.co.za It is strongly advised to seek expert advice from such an industry specialist. Bosun cannot accept any responsibility for inappropriate use or incorrect application of sealants. Bosun strongly advises that concrete products only be sealed six months after installation in order for them to fully cure on site and for possible efflorescence to run its course. It must be accepted that sealants may have an effect on the colour of the paving and its slip/skid resistance. Sealants may also require on-going maintenance during the life of the paving. It is also important that the surface must be dry, clean and efflorescence-free before any sealer is applied.

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Information: Maintenance

Maintenance of Bosun Dry Cast Concrete Pavers continued Benefits of sealing your paving: • • • • • •

Improves its appearance. Under some circumstances, prolongs its life. Helps seal the jointing material. Inhibits weed growth. Stain prevention (especially from oil based stains). If you choose to apply a sealant to your paving call in a paving specialist to do the job.

Efflorescence The white film that might appear on the surface of concrete, clay and natural stone products is called efflorescence. Apart from the discolouration efflorescence is harmless. It is best described as being a temporary skin problem and not a deep-seated disease. How it occurs? Efflorescence is a natural phenomenon that occurs through a complex Chemical or Physical process or a combination of the two. Detailed information on Efflorescence is available for research on the internet, or consult the Concrete Manufacturers’ Association website Bosun’s take on efflorescence We are not bigger than nature. Bosun can therefore not guarantee efflorescence-free products. (Pre- or post-installation.) Bosun is constantly experimenting with aggregates and additives which might minimise or prevent efflorescence, although the soil beneath the paving might actually be the cause of the efflorescence. The Cure We believe the best cure for efflorescence is just to leave it as it will go away eventually. Experience has taught us that some paving installations have had efflorescence for a few weeks only, while others have been affected for months. Sometimes efflorescence is recurring and sometimes it appears only once. Therefore one can never predict the outcome of a specific site. What we do know however is that efflorescence is temporary. When you “Google” (Remove efflorescence), there are around 260,000 results. Most of them recommend washing the affected material with a weak acid solution. It might however re-appear within a day. As mentioned before, one cannot force nature to change. Bosun believes that the use of acid is a risk not worth taking. If however you are forced and/or prepared to take the risk, we recommend consulting the following British web page, for an objective and very comprehensive take on efflorescence, together with some options on removal: http://www.pavingexpert.com/eff01.htm Note: The information above on the cleaning and maintenance of precast concrete paving is a general guideline only and is not intended to be complete and comprehensive. It is particularly important with all cleaning methods that they first be tested on a small, preferably inconspicuous area, to determine their effects before starting work on a larger area.

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Information: Guarantee

Bosun 5 Year Guarantee Bosun undertakes to replace, at its own cost, any Bosun products that suffer from defects in material or manufacture within a period of 5 (five) years from the date of delivery thereof to the customer.

Bosun’s liability under this guarantee is as follows: 1. The replacement of defective goods. Bosun will replace defective products at its own cost. Bosun will pay the costs associated with the delivery of the replacement products to site, and for the removal of the defective products. 2. Other costs associated with remedial work. Bosun will pay the direct costs associated with the replacement of defective products. Specifically Bosun will pay for bedding sand (if required) and for the cost of labour required to uplift defective products as well as the installation. Bosun is entitled to uplift the specific pavers or kerbs that are defective and to replace them (as opposed to uplifting and replacing all of the products).

Bosun’s liability under this guarantee does not extend to: 1. Defective installation. Bosun’s liability under this guarantee is conditional upon the products having been installed in compliance with SANS 1200MJ. 2. Exposure to Conditions beyond Specifications / Industry Norms. Bosun is not liable for any product that fails as a result of the products having been exposed to conditions beyond the specification for the product, or for products that fail because they have been either incorrectly specified, or because they are applied contrary to industry norms for such products. Bosun is not responsible for breakages that occur on site as a result of poor handling. 3. Indirect or consequential damages. Bosun’s liability is limited to the express provisions of this guarantee. Accordingly (and without limitation) Bosun is not liable for penalties, consequential losses or for any other indirect damages. 4. Failure by the customer to report defects to Bosun & to allow Bosun to replace the product. Bosun’s promise is that it will replace and install products that are defective (on the terms and conditions of this guarantee). The Customer must immediately notify Bosun of any alleged defects in order for Bosun to assess the problem and, where necessary, to take the necessary remedial steps. Bosun’s obligation to replace and install new products will immediately terminate in the event that any such remedial work is undertaken by the Customer, owner or by any third party other than Bosun, or its nominated contractor. 5. Efflorescence, colour variation & failure to maintain. Paving products manufactured utilising concrete may present with efflorescence. Similarly, over time, the colour on any coloured product may fade. Bosun does not warrant that the products will not present with efflorescence or, over time, with a colour variation (from the original product) and accordingly this guarantee does not extend to products that suffer from efflorescence, or that fade over time. Further, Bosun’s liability under this guarantee is conditional upon the product having been properly maintained. Sprawling and damage resulting from a failure to replace and maintain grouting consistency is not covered by this guarantee. Bosun conducts business in terms of its Standard Trading Terms and Conditions (copies of which are available on request). This guarantee shall be read in conjunction with the Bosun Standard Trading Terms and Conditions, and, save to the extent that the terms of this guarantee are expressly at variance with the Bosun Standard Trading Terms and Conditions, the Bosun Standard Trading Terms and Conditions shall apply.

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Information: Installation tools

AVAILABLE AT BOSUN

String Tight Straight and square edges are required when installing paving bricks, kerbs and slabs. Skew plumb lines are often a problem on site. The STRING TIGHT system provides a clearance of approx. 4-5mm between pavers and the string line. An essential tool for any contractor who lays paving blocks or carries out repairs to paved surfaces. Adjustable to fit any size and shape of paver.

Paving Block Extractor

Kerb Handle

Alignment Bar

Adjustable Paver Transport Cart

For aligning the paving bricks before they are permanently set.

For the effortless transportation of bound or loose pavers.

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Paving Slab Handles Used to handle heavy pavers like the Large and Slimline Urban pavers. XXL Urban pavers could be handled by a paving handle on each side.

Unimobil (For Hire)

Measuring and Marking Tool

The Unimobil is used to handle large paving units like the Bosun An essential aid for the exact measuring and marking of lengths XXL Urban paver. and angles on pavers.

Block Cutter

Halder Paving Mallet

Cuts pavers up to 300mm wide in less than a second. Both blades, top and bottom, have 4 cutting edges, thus ensuring a long life. The blades can be turned quickly and easily.

These non-marking mallets are much heavier and more durable than rubber mallets available in South Africa. It is used to level large pavers and kerbs. All components are replaceable.

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Information: Installation tools An alternative to cement grouting For more than 20 years Romex has been the world’s leading manufacturer of paving jointing materials. Their high quality resin based grouting solutions have been developed to overcome the shortcomings of cement grouting. Romex grouts are tried and tested and have been used on paving installations throughout the world.

AVAILABLE AT BOSUN

Romex resin is imported from Germany, but the specially graded silica sand used in conjunction with it, is sourced in South Africa. It is therefore more expensive than cement grouting, but when applied correctly, it is guaranteed not to crack and break up. Benefits: • Designed for a single purpose: Jointing of paving • Reliable and long lasting • Does not crack or disintegrate • Can be used for jointing repair jobs • Consistent, compressive, flexural and adhesive strength • Fast and simple installation • No staining • Resistant to weeds and digging ants

Romex is easy to install in just a few simple steps:

1

4

Pour the two part mix into the aggregate.

Pour the mixture onto the area.

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2

5

Mix them together thoroughly.

Sweep the mixture into the grouting gaps. Make sure the mixture is evenly distributed.

3

Wet the pavers onto which the mixture will be applied.

6

Wash the excess Romex mixture off the pavers.


Sealing, stabilising and protecting your paving Since 1993 Resiblock Limited, the block paving sealer expert, has sold block paving sealers, Whether it be for industry, commerce or home, Resiblock solutions give accelerated joint stabilisation without sand erosion or ongoing maintenance. AVAILABLE AT BOSUN Benefits of using Resiblock • Resiblock stabilises jointing sand and ensures it doesn’t get eroded or washed out from between the joints. • Ensuring the stability of the jointing material will drastically increase the lifetime of paving. • Resiblock is ideal for areas with a steep slope or where joints are susceptible to erosion. • Resistant to weeds and digging ants. • Fast and simple application • Resiblock is not only a joint stabiliser but also doubles as a high quality sealer that will protect your paving from stains and scuff marks. Reasons for Paving Failure • Jointing sand keeps pavers locked, if it becomes washed out leaving an empty space between two pavers then they will be able to move and not stay firm under traffic. • This leads to failure of sub-base and in wet conditions the sub-base material will be pumped out as can be seen in the picture below. • Water has penetrated the paver joints and has become trapped in both the sub base and the sand laying course material. • Subsequent trafficking has led to the deformation. • Once saturated, both the sub base material and the laying course material lost stability and proved insufficiently stable to support traffic. • The pavers have cracked as a result of the surface deformation.

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Information: Product specifications

Thickness

Weight per unit

Units/ Pieces per m2

m2 per pack

Pavers 400mm x 400mm Hermetic Paver Bevel Bond Paver Split Bevel Bond Paver Rio Rocoso Bevel Smooth Ethnic Paver Bosun Bullnose (10 per Linier meter) Bevel Bond 60mm Paver Venetian Paver Bosun Cobbles Rio Rocoso Interlocker Paver Shale Interlocking Paver 60mm Interlocking Paver 100mm x 200mm - Urban Paver 150mm x 200mm - Urban Paver 200mm x 400mm - Urban Paver 300mm x 400mm - Urban Paver 600mm x 900mm - Urban Paver Waterwise Paver (Permeable paver) Citylock Paver 80mm Interlocking Paver 300mm x 120mm - Linneo 600mm x 240mm - Linneo

35mm 50mm 50mm 50mm 55mm 55mm 60mm 60mm 60mm 60mm 60mm 60mm 60mm 60mm 60mm 60mm 80mm 60mm 60mm 80mm 80mm 80mm

12 kg 2.15 kg 2.15 kg 2.15 kg 3.7 kg 3.6 kg 2.6 kg 1.90 kg 5.8 kg 2.6 kg 2.6 kg 2.6 kg 2.6 kg 3.7 kg 11 kg 17.5 kg 95 kg 4.35 kg 3.5 kg 3.5 kg 5.66 kg 23 kg

6.25 50 50 50 33 33.33 50 72.7 22.2 50 50 50 50 33.33 13 8.33 1.85 Vary 39 50 27.77 6.94

9.6 m2 11.52 m2 11.52 m2 11.52 m2 10.8 m2 5.4 m2 10.56 m2 5.89 m2 9.9 m2 10,56 m2 10,56 m2 10,56 m2 10.56 m2 9.9 m2 10.56 m2 10.56 m2 10.8 m2 9.3 m2 9.87 m2 9.6 m2 8.64 m2 8.64 m2

Kerbs Figure 3 - 1000mm Figure 3 - 330mm Figure 4 - 1000mm Figure 4 - 330mm FFigure 7 - 1000mm Figure 7 - 330mm Figure 8B - 1000mm - Standard Figure 8B - 330mm Figure 8C - 1000mm - Standard Figure 8C - 330mm Figure 12 - 500mm (2x 500mm Units) Figure 14 - 1000mm Channel Kerb - 1000mm Transition Kerb - 1000mm 150mm x 150mm Edge Beam - 1000mm Delineator Kerb - 1000mm

300mm 300mm 250mm 250mm 280mm 280mm 175mm 175mm 200mm 200mm 150mm 125mm 150mm 280mm 150mm 300mm

110 kg 36 kg 80 kg 26 kg 105 kg 35 kg 86 kg 27 kg 107 kg 36 kg 12/24.8 kg 72 kg 60 kg 120 kg 55 kg 115 kg

-

Grass Blocks Grass Blocks

100mm

Retaining walls Verso Block - No Lip Verso Block - With Lip Robust Retaining Wall Block

200mm 200mm 250mm

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Units/ Pieces per pack

Weight per pack

Pack Dimensions WxLxHmm

60 576 576 576 360 180 528 424 220 528 528 528 528 330 132 88 20 264 385 480 240 60

720 kg 1240 kg 1240 kg 1240 kg 1240 kg 642.6 kg 1370 kg 805 kg 1280 kg 1300 kg 1300 kg 1300 kg 1320 kg 1320 kg 1380 kg 1440 kg 2020 kg 1200 kg 1340 kg 1580 kg 1359 kg 1380 kg

800 x 1200 x 550 800 x 1200 x 600 800 x 1200 x 600 800 x 1200 x 600 760 x 1200 x 670 710 x 1000 x 500 800 x 1220 x 660 670 x 1280 x 440 760 x 1200 x 730 800 x 1200 x 670 800 x 1200 x 670 800 x 1200 x 670 800 x 1200 x 670 760 x 1200 x 730 800 x 1200 x 820 800 x 1200 x 670 900 x 1200 x 1000 900 x 1000 x 680 980 x 1150 x 660 800 x 1200 x 800 800 x 1200 x 720 800 x 1200 x 720

-

-

12 36 12 36 12 36 12 24 12 24 100 Units/50m 10 20 6 25 12

1188 kg 1112.4 kg 966 kg 936 kg 1209.6 kg 1126.8 kg 1056 kg 741.6 kg 1239.6 kg 864 kg 1240 kg 742 kg 1246 kg 720 kg 2000 kg

610 x 1000 x 960 750 x 1000 x 900 620 x 1000 x 800 610 x 1000 x 840 750 x 1000 x 900 750 x 1000 x 950 840 x 1000 x 950 620 x 1000 x 830 840 x 1000 x 950 620 x 1000 x 940 760 x 1000 x 770 610 x 1000 x 700 800 x 1000 x 850 600 x 1000 x 580 810 X 1000 X 800 800 x 1000 x 940

35 kg

4.2

-

40

1480 kg

810 x 1200 x 1000

28 kg 28 kg ±49kg

-

-

24 24 18

681.6 kg 681.6 kg 882 kg

850 x 930 x 840 850 x 930 x 870 750 x 800 x 900


Expect the Best

CONTACT DETAILS GAUTENG Tel: 011 310 1176 Fax: 011 310 1178 Email: gp@bosun.co.za

NORTH WEST Tel: 012 250 1711 Fax: 012 250 1708 Email: nw@bosun.co.za

EASTERN CAPE Tel: 041 405 0100 Fax: 041 405 0199 Email: ec@bosun.co.za

Physical Address: Corner Cresset & Musket Roads Midrand Industrial Park Midrand

Physical Address: 1892 Pendoring Street Brits Industrial Area Brits

Physical Address: Corner Neptune Road & MR435 Coega Industrial Development Zone Port Elizabeth

Postal Address: PO Box 7313 Halfway House 1685

Postal Address: PO Box 637 Brits 0250

Postal Address: PO Box 61176 Bluewater Bay 6212

Disclaimer: Although the information in this book is presented in good faith and believed to be correct, Bosun makes no representations or warranties as to the completeness or accuracy of the information including variances in colour, size, texture and weight. Due to different aggregates used in various regions, variances will occur.

Bosun book v5 jan2017  

Bosun Paving, Kerb and Retaining Wall Handbook

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