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LCT Contents
Introduction PAGE
Introduction 0.1 This Document 0.2 Abstract 0.3 Strategic Proposal
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Section 1: Design Principles 1.1 The Elements 1.2 The Hall
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0.1 This Document Whereas the other documents explore the thesis project from the perspectives of audiences and disciplines outside traditional architecture, the objective of appropriating the Approved Document format is to set out how the project responds to the profession of architectural practice, including the regulatory context and technical resolution.
Section 2: Structural Strategy 2.1 Structural Principles 2.2 Massing 2.3 Existing Detail Section 2.4 Proposed Detail Section 2.5 The Wall 2.5.1 Kit of Parts 2.6 The Frame 2.7 Construction Sequence 2.8 Phasing 2.9 Material Strategy 2.7.1 Cladding 2.7.2 Elevation Tests 2.10 Relation to Existing 2.10.1 Proposed wall to Existing 2.10.2 Foundation 2.10.3 Openings 2.11 Structural Constraints 2.11.1 Geology 2.11.2 Flooding
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0.2 Abstract There are now more spare bedrooms in the UK than ever before. As the challenge of finding a supply of new homes grows, the call to Live Closer Together looks to the spare space in our suburbs as a potential community-led solution. What if we already have enough residential space, we’re just not using it well enough? The thesis project Living Closer Together responds to this challenge, seeking to develop architectural techniques to unlock 'spare' space and turn it into a new and empowering land supply.
Section 3: Environmental Approach 3.1 Environmental Constraints 3.2 Ventilation 3.3 Daylighting
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Section 4: Regulatory Response 4.1 Building Regulations 4.1.1 Access and Use of Buildings 4.1.2 Fire Safety 4.1.3 Resistance to Passage of Sound 4.2 Lifetime Homes
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Section 5: Implementation 5.1 Funding 5.2 Design Team 5.3 Stakeholders 5.4 Timeline
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0.3 Strategic Proposal The individual nature of the home forestalls a singular design. Thus, the design process has been one of developing an architectural language capable of taking many forms and being adapted to many sites. The resultant design is therefore a kit of parts; the resolved plans submitted are intended as experiments that test this language and provide suggestions for how it might be deployed.
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LCT Section 1: Design Principles The architectural language is comprised of two key elements: the wall and the frame. These two fundamental elements can be in conjunction, or the frame in isolation, to adapt existing homes and convert their 'spare' space into new dwellings. The language can also be used to build new freestanding dwellings on pocket or infill sites. The intention of the wall is to provide a backbone to the new dwellings that acts both as a planning mechanism for controlling both the number of new dwellings and particular relationships, such as sightlines. These solid, dense elements act as bookends that encase the main programmatic space of the new homes. They also provide a conduit through which services can be routed. It is envisioned that these elements would be manufactured off-site to a variety of designs. Different companies could be set up to provide different styles or options. Walls can then be purchased from catalogues by the space-sharing homeowner and would be delivered to and erected on-site. The frame element is intended as an intermediary between the walls and the existing homes. A basic construction technique, the timber frames enclose the walls and connect to the existing dwellings. This element would be constructed on-site by a local builder.
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Section 1: Design Principles 1.1 The Elements By breaking the construction of the new suburban homes into elements, the opportunity for suburbanites to actively engage with the architecture of their home is intensified. The permanence of the walls support a greater level of flexibility in the
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LCT framed structures. This embodies the programmatic role of these different spaces: the hall, created by the walls, is the central social space, encompassing kitchen, living room and dining room. The frames house 'soft' space: rooms that are exchanged between dwellings as needs change.
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Section 1: Design Principles
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1.2 The Hall The Wall elements combine to create an anchor space, around which the frames, housing more flexible rooms, are arranged. This is a moment within the home of density and ontological security, that provides a strong both tectonic and programmatic foundation to the home.
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Section 1: Design Principles
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Section 2: Structural Strategy 2.1
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Structural Principles
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Section 2: Structural Strategy
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2.2 Massing
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Section 2: Structural Strategy 2.3 Existing Detail Section 25 Benbow Drive Scale 1:50 The town was built during the late 1970s and 1980s. From information about the town's construction and recent planning applications it is reasonable to assume an external wall buildup of blockwork faced with brick or weatherboarding and traditional timber floor and roof constructions.
Attic Existing external wall build-up: 75mm brick facing 100mm cavity 100mm blockwork 50mm battens 12mm plasterboard
Bedroom
Living Room
fig. 2.3 Archive photo of houses in the town under construction
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Section 2: Structural Strategy 2.4 Proposed Detail Section 25 Benbow Drive Scale 1:50 At least one module of the Frame structure mediates between the Wall elements and the existing homes.
Hall
Frame
Attic
Bedroom
Hall
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Bedroom
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2: Structural Strategy 2.5 The Wall 25 Benbow Drive Scale 1:20 This is a pre-fabricated element. They are manufactured as off-theshelf products by a variety of companies, and can be ordered in combination by homeowners to be assembled on site and kick-start the process of densification.
fig. 2.5.1
The structure is likely to vary from manufacturer to manufacturer. It could include a studwork structure as drawn here, clad in timber, tiles or curved plaster as in the instance of the House of Muses pavilion by Gruppe; a CLT panel; or solid masonry.
fig. 2.5.1 Precedent: House of Muses by Gruppe
fig. 2.5.2 Model tests: clay and concrete
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Frame external cladding option: 50mm insulation Breather membrane 40mm counter battens & ventilation zone 25mm battens laid in a grid 22mm vertical planks with butt joints *Insect mesh to ventilation zone openings
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Proposed flat roof build-up: 6mm EDPM Rubber roofing 18mm OSB 75mm insulation Breather Membrane 200mm x 50mm ceiling joists at 400mm centres 200mm insulation between joists 15mm battens laid in a grid 12mm plasterboard
Proposed Wall floor build-up: Floor finish, eg. 22mm timber floorboards 12mm chipboard 75mm insulation 150mm CLT panel 25mm battens 12mm plaster to match Wall elements
Proposed floor build-up: Floor finish, eg. floorboards 12mm chipboard 200mm x 50mm floor joists at 400mm centres 100mm insulation between joists 15mm battens laid in a grid 12mm plasterboard
Frame build-up option suitable for interior: 25mm solid plaster skin 250mm x 75mm studs at 400mm centres 250mm insulation between joists 25mm solid plaster skin
Proposed ground floor build-up: Floor finish, eg. floorboards 40mm self-levelling screed Damp-proof membrane 150mm insulation Suspended block and beam concrete floor: beam depth 155mm, block depth 100mm
300mm In-situ concrete ground beam 100mm mini-pile to a depth determined by specific site conditions
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2: Structural Strategy
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2: Structural Strategy
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2.5.1 Kit of Parts Breaking the key tectonic element of the home into a series of products seeks to create an intense variety on site. This responds to the core ideology developed during the thesis of the role of the suburban home in the individual's process of self-actualisation. Through imprinting their identity on their home, the suburbanite's identity is created and continues to be shaped in a didactic conversation. Such a kit of parts approach, engaging with the legacy of the multi-authored pattern book in early suburbia, allows for the creation of homes as individual as the residents within. A series of designs with multitudinous possible combinations also allows for the proposal to be applicable to the wide variety of possible sites and conflicating geometries present on site.
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2: Structural Strategy 2.6 The Frame 25 Benbow Drive Scale 1:20 The Frame is the mediating element between the 'found ruins' of the Walls and the existing dwellings. Timber construction suits this purpose due to the ease with which it can be constructed on site, in particular the possibility of cutting and adjusting on site. This is the low-tech element, which would be constructed on-site by local builders or self-builders, and be easily adapted and 'hacked' over time.
Proposed flat roof build-up: Please refer to p.10
frame detail section
Proposed floor build-up: Please refer to p.10
Proposed retrofit floor buildup: Floor finish, eg. floorboards Floating layer of two layers of 8mm board material, layed loose on: 25mm mineral wool insulation Existing floor build-up 100mm insulation added within cavity Second layer of plasterboard added to ceiling
Proposed ground floor build-up: Please refer to p.10
fig. 2.6.1 Design development: Material Matrix
fig. 2.6.2 Precedent: House Bernheimbeuk by Architecten de Vylder Vinck Taillieu
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2: Structural Strategy
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2.7 Construction Sequence The tectonic elements correspond to a phasing strategy on site.
2.7.1 Existing A number of homeowners agree to share their plots to develop new dwellings.
2.7.2 Halls erected The Halls are employed as a planning strategy for controlling the number of new dwellings. The most permanent element, they are constructed first as 'found ruins'.
2.7.3 Frames Timber frames then begin to be constructed around the halls, enclosing these spaces and bridging to the 'spare' space in the existing homes.
2.7.4 Cladding The frames are then clad in materials of the residents' choosing. The cladding changes over time as rooms are exchanged, allowing the expression of the boundary between different dwellings.
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2: Structural Strategy 2.8 Phasing The densification would happen over time as the movement picks up and the technique is tested and refined. The Design Guide
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2: Structural Strategy 2.9
Material Strategy
2.9.1 Cladding The cladding is intended to be a shorter lifespan element that is altered in response to the changing boundaries within the home. As rooms are exhanged between dwellings, the facade is updated to maintain a clear definition between dwellings. The material palette updates that which appears in the Design Guide for Residential Areas from which the original town was built, including timber cladding, more traditional East Anglian weather-boarding, corrugated materials and zinc. The variety of materials creates a patchwork aesthetic that connects visually with the existing character of the town. fig. 2.5.1 Material palette from the 1973 Design Guide for Residential Areas by Essex County Council
fig. 2.5.2 Precedents: Tinggaarden and The Blue Corner by Vandkunsten Architects
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2: Structural Strategy
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2: Structural Strategy
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2: Structural Strategy 2.10 Relation to Existing
fig. 2.10.1
fig. 2.10.2
fig. 2.10.3
2.10.1 Proposed Wall to Existing An insulated DPC between the frame structure and existing wall is the recommended junction. The existing wall is then lined with battens, insulation and plasterboard to present a new surface to the new-built room. 2.10.2 Foundation Using a site with existing residential buildings raises the issue of disproportionate collapse or subsidence as a result of the new structures. To this end it is proposed that no extra load will be put on the existing dwellings. A perimeter of 1.5m will be maintained around all existing structures, with in-situ concrete ground beams cantilevering within this zone.
fig. 2.10.1 Proposed wall to existing external wall junction
2.10.3 Openings The Design Guide places a preference on using existing openings in the homes. Where this is not possible, simple new openings can be created by local builders using PFC steel lintels to support the two leaves of the existing cavity wall.
fig. 2.10.2 Sketch of foundation strategy for avoiding disturbing the existing home.
fig. 2.10.3 New openings detail sketch
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2: Structural Strategy 2.11 Structural Constraints
fig. 2.11.1
fig. 2.11.2
2.11.1 Geology Located within the Thames Basin, the bedrock of the site is silty clay, with some alluvium deposits (silt and sand) in the south of the town, towards the River Crouch. It is judged that this geological context will provide sufficient stability for mini-pile foundations. 2.11.2 Flooding The 'riverside country town' is located within estauries of and above the River Crouch. The strategy in the construction of the town as existing was to limit the number of homes located within the higher flood risk zone of flood risk 2, shown in darked hatch opposite. The project proposes to continue this masterplanning strategy to limit the risk of flood damage to dwellings. Further to this, the existing flood defences have been judged sufficient for the new development site proposed by Chelmsford City Council and thus no further intervention is judged as required.
fig. 2.11.1 British Geological Society map of geological context.
fig. 2.11.2 Flood risk in the town.
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Section 3: Environmental Approach
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3.1 Climactic Conditions South Woodham Ferrers is in East Anglia, an area of the country defined by the large tract of low, flat land of the Fens. Though there is marked temperature and sunlight variation between two clearly defined seasons, it does not pose as much of a challenge as particularly the temperature swings on the continent. The specific challenge the climactic conditions pose to the design is how to provide living spaces that provide enough fenestration to take advantage of the limited summer sun, whilst maintaining enough enclosure, thermal mass and insulation to ride out the colder months. This has been considered in the design through the use of the Wall elements as thermal mass to the main space, including surrounding them with other heated inhabited rooms, and high levels of insulation in the building envelope.
fig. 3.1.1 Sun Path Diagram
East Anglia is also one of the most sheltered areas of the UK due to the worst storms typically being Atlantic in origin. fig. 3.1.2 Average Monthly Temperatures
fig. 3.1.3 Average Monthly Rainfall
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Section 3: Environmental Approach 3.2 Ventilation The central space of the hall, capped with skylights, provides a central chimney that creates an airflow of natural ventilation through the rest of the dwelling. Further to this, the temperate conditions and residential programme of the proposal suit the ventilation strategy to a comfort theory where users adapt their surroundings to fit their requirements. If more ventilation is required, a window can be opened. This strategy is also applicable to the thermal conditions of the home.
fig. 3.2
Ventilation strategy
fig. 3.3
Daylighting strategy
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3.3 Daylighting Due to the unwanted nature of and high potential for invasive overlooking from new dwellings onto existing, each Hall is roofed with skylights. This serves to create a new vertical axis within the new suburban homes, along with the double-height space and mezzanine walkway surrounding the main room. The skylights will be complimented where possible with fenestration targeted to frame specific views. This strategy takes best advantage of the zenith, creating light and bright main spaces whilst minimising overlooking.
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Section 4: Regulatory Response 4.1 Building Regulations 4.1.1 Access and Use of Building The urban extent of the town has gentle topography which does not pose a significant challenge to constructing or accessing the proposed new dwellings. Levelling will occur as necessary during construction to provide level access to each dwelling. The new homes follow the existing pattern on site of a primary ground floor and maximum two stories above. The lack of basements existing on site at present suggests the site is unsuitable for such construction. All front entrances provide level access from the pavement.
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Parking is provided in small community clusters. 4% of the bays are designated for disabled people and are sized according to Part M. In the instance of greater disabled vehicle access being required, an internal garage can be provided within the house. All staircases have a maximum rise of 170mm and going of 250mm to comply with both Part K of the Building Regulations and Lifetime Homes guidance. The flexibility and ease of construction of the structural frame element provides an easy method to introduce a through-floor life, as recommended in Lifetime Homes Guidance.
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Section 4: Regulatory Response 4.1.2 Fire Safety As recognised in Part B of the Building Regulations, the provision of means of escape from these relatively typical dwellings is relatively simple.
fig. 4.2
fig. 4.3
Means of Escape Stairs within new structures are located within fire compartments that allow the evacuation from all first floor accommodation without the need to pass through the main space, which is the most likely site of fire due to the presence of the kitchen. In the renovation of the existing dwellings a fire compartment is created where it is currently lacking to bring the existing dwelling up to contemporary standards. All ground floor rooms are provided with a minimum of one window meeting paragraph 2.8 of Part B.
fig. 4.3
Sketch section showing chimney strategy.
Control of Smoke Locating the kitchen in the double-height space of the Hall allows this space to act as a chimney for the dispersion of smoke away from the other inhabited areas and means of escape. The escape routes from the dwellings avoid this space so as to provide smoke-free egress from the dwelling. Fire curtains were considered as an alternative option for managing smoke within the Hall but were discarded due to cost implications. Prevention of Fire Spread Compartmentation is used within the dwellings, both to provide a series of stops to fire spread and also to provide a minimum level of separation that enables the exchange of rooms between dwellings, also from the perspective of acoustics. All materials used in the construction and future adaptation of the dwellings are fireresistant and meet the necessary guidance of Part B. 60 minute fire resistance to all escape compartments. 90 minute fire resistance to be provided between all dwellings. Suitable fire alarms to be provided throughout.
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Section 4: Regulatory Response
Door for escape Window for egress
fig. 5.1
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60 minute fire resistance 90 minute fire resistance Kitchen Escape route
Plan showing means of escape and compartmentation.
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Section 4: Regulatory Response 4.1.3 Resistance to the Passage of Sound The subdivision of the existing homes into multiple dwellings involves the creation of new party walls and party ceilings. In order to meet Part E of the Building Regulations where this occurs the build-up needs to be improved to meet the requirements shown to the right.
fig. 4.3.1
fig. 4.3.2
fig. 4.3.3
Wall The side of the new party wall to the new dwelling should be clad to meet the requirements shown to the right. An independent frame should be constructed that maintains a 10mm gap to the existing wall at all times. This should be lined with minimum 25mm mineral wool insulation, then clad in two skins of plasterboard, to be fastened together with staggered joints. Ceiling Two options are presented in Part E. The first option is to install a suspended ceiling, with the same principles of the wall detail. An independent frame is constructed and insulation added to aid in acoustic insulation. However, as the existing dwellings have restricted head height, the minimum 125mm depth of this option is in many cases prohibitive.
fig. 4.3.1 The required retrofit party wall detail
fig. 4.3.2 Ceiling option one: suspended ceiling
fig. 4.3.3 Ceiling option two: platform floor
The second option is to install minimum 100mm mineral wool insulation within the existing floor cavity and top it with a resilient layer of mineral wool and a double-sheathed floating layer of board material. This provides a much slimmer build-up and also keeps the disruption and work to the new dwelling side of the party wall.
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Section 4: Regulatory Response 4.2 Lifetime Homes As part of the strategy for incentivising the redevelopment and densification of the town, the proposal envisages that an element of the quid-pro-quo development structure would be that each existing dwelling would be both aesthetically and practically improved. This is achieved by bringing the existing dwellings up to Lifetime Homes standards in the process of their adaptation. This substantially improves the existing stock and represents value creation as a result of the densification, both for the homeowners whilst resident and also postsale.
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The guidelines require: - A potential bedroom on the ground floor; - A ground floor W.C. with the potential to be converted to a wetroom; - A minimum 750mm clear space around beds; - A minimum 1200mm clear space in front of kitchen units; - Living rooms to have a clear turning circle of 1500mm; - A possible 1200mm zone for future installation of a through-floor lift. They recommend: - Kitchens to be arranged with oven and hob, sink and counter space for each in an unbroken run.
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Section 5: Implementation 5.1 Funding 5.1.1 Homeowner-led The proposal suggests that the densification of the town would be led and funded by individual homeowners, potentially with public support or underwriting of the necessary loans. Many of the target residents are within an age-group who are typically asset-rich but income poor. Such assets could be borrowed against in order to provide future income. 5.1.2 Developer-led An alternative model, more suitable for larger schemes or where a number of plots have agreed to collaborate, would be the developer model as exemplified by the polykatoikia in Athens. Here, the financial risk but also much of the financial gain from densifying would be carried by the private developer, as in traditional forms of housing supply such as Site Location 7.
LCT The architect is involved at two scales. Strategic and spatial skills are employed at a neighbourhood scale in the mapping and analysis of 'spare' space, including the developing of action-plans to inform potential sites for new homes. This sees the architect become involved in the shaping, regulation and control of the development. At the smaller scale, the architect would adopt the early suburban model of pattern books, designing the individual elements and suggesting potential combinations that go together to make the new homes.
5.1.3 New Suburban Development Co-operative The process is overseen by a semi-public body that acts as a subsidiary to the Town Council. This would be partly funded by CIL contributions from larger schemes developed within the town. As it stands, if the town adopted a Neighbourhood Plan it would stand to gain 25% of such contributions, as opposed to 10% without. 5.2 Design Team The Co-operative would be a body comprised of a wide range of practitioners including but not limited to planners, architects, consultants and residents. Using the example of my experience working on the Neighbourhood Plan, the Co-operative would exist between the role of the Steering Group, in its inclusion of a diverse range of specialisms and strong resident voice; and the Town Council, in its level of organisation and professionalism.
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Section 5: Implementation
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6.3 Potential Stakeholders As the proposal concerns adding extra population to the town, the number of stakeholders potentially affected is very diverse and large. The figure right shows the list of potential stakeholders that I was involved in compiling as part of the Neighbourhood Plan Steering Group.
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Section 5: Implementation 6.4
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Implementation Timeline
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