Issuu on Google+

1. Prithwe Community - Agrihomes This project can create awareness in the minds of urban population, where people used to see nature on screens, eat breads & milk out of the plastic bag and breathe the carbon di oxide filled air, about natural living. Finally we are all humans & as those, we need the earth. Many of us realize that we cannot buy health & happiness, that we can only bring it out when we are ourselves in our mother nature. By this project, it is possible to reconnect & build bridges between urban & rural societies for better understanding & learning from nature. The large piece of land selected for this project lies on contour site, over looking the terrain. Rather than farm relating only to the conventional weekend recreation these farmhouses will turn into exclusive ‘Agrihomes’, where comfort is achieved through natural living. Following the intention of natural living the houses will be designed according to the local climate and will be built of exceptional ecological & vernacular materials & techniques. Each house in the project will be erected according to the vastushastra principles, produce its own energy; will conserve energy, water & ecological value of the land. The surrounding farm will be spacious & designed according to premaculture principles. Embedded in green the Agrihomes society will have several leisure time facilities like walking & jogging tracks, sports facilities, lawns for reunions etc. Homes were you would like to come to de-stress, revive and feel happy would be made following strict norms of Vastu and Bau-biology. Sustainable and Indian Green philosophy of Prithwe institute would be demonstrated in each homes were locally available, natural and healthy building material would be used for construction. Bamboo, rammed earth and basalt stone would be the main structural elements. These 2 or 3 bedroom homes would also have a cow shed, personal water body, helpers den, open decks, porticos, outdoor dinning and yoga spaces. Native landscaping would be included in the Permaculture design.

Bamboo House

Urban Lifestyle

5. Site Analysis

5.1 Accessibility The site for the Agrihomes is accessed from South East. As site is situated on hill slope there exists less natural pathways made by villagers, tress passers & animal. The road network created on site by taking into consideration the slope & gradient of site & maximum allowable gradient of road. 5.2 Topography The site is situated on hilly terrain, with gradients between 1:2 to 1:6. Steep valleys & contours are indicated in the adjoining map. Soil Characteristics The soil can be categorized as silty clay to silty clay loam (sand: 21 – 24%, silt: 32 – 27%, clay: 46 – 48%) 5.3 Climate The area for “Prithwe” falls under the tropical – wet climate zone. A tropical rainy climate covers regions experiencing persistent warm or high temperatures, which normally do not fall below 18 °C. In the region around Pune, the annual dry bulb temperatures range between 24 and 38°C.


Average annual temperature: 22.5 – 25 deg. Wind speed: 33 – 39 m/sec Main wind direction: southwest Monsoon: June – September Average rainfall: 150 – 250 cm 5.1 Accessibility Map

5.2 Topography Map


5. Site Analysis

5.4 Vegetation The cultivated plantation is rare, but intensifying towards the streams. Areas on the lower slopes are used for rice cultivation on terraces. Moving upwards, the hills are occupied by tree plantations, mainly cashew. Various fruit trees can be found, such as mango, amla and the holy udumbara. The upper vegetation has been left to nature, which has given ground for acacia, eucalyptus and various kinds of pines, wild bamboo, flowery shrubs such as jasmine, various thorns and grasses. The slopes show several open pockets with rocky ground between the dense vegetation.

5.5 Hydrology – water harvesting possibilities The adjacent river is dammed 17km east at the location of Bhor. There it forms a huge reservoir holding the water for agricultural, domestic and industrial use of the region for the months after monsoon. The site is cut by various natural water streams that channel the water from the hilltop towards the river. In monsoon times these are carrying a lot of water, but shortly after monsoon, they are already quite dry and the water keeps on moving underground. The groundwater level seems to be high and several natural water sources can be found on the site. The moderate hydraulic conductivity of the soil gives a good base for natural water holding arrangements. Swales and diversion ditches on contours can be a good solution to hold back rainwater in the monsoons and store it in the soils, prevent from erosion, sedimentation and runoff of important nutrients. These swales can be connected to the natural water sources on the site to collect water from there and distribute it over the site in after monsoon times. 5.4 Vegetation

5.5 Hydrology

5. Site Analysis

M a i n

W i n d

D i r e c t i o n

5.6 Microclimatic Analysis

Conclusion The region falls under warm & humid climatic zone, so that favorable micro-climatic conditions can be achieved by allowing wind & obstructing sun on site. Steps of Micro-climatic Analysis 1. Annual shadow pattern analysis 2. Annual wind flow analysis 3. Preparation of site shadow & wind pattern drawing to grid cell system 4. Micro climate of each grid cell can be analyzed by over laying sun shadows & wind pattern drawings.

Flat Land getting maximum solar radiations & un obstructed wind flow - Most suitable location for renewable energy sources

6. Design Approach

6.3 Green Architectural Capability

6.1 Need:


To spend time with nature for mind relaxation,

Breathing fresh air

To live in environment which is free from all types of manmade pollution.

6.2 Aim & Objectives: •

To Promote natural lifestyle in urban schedule.

To Encourage urban people for organic & sustainable farming.

Climate responsive construction.

Use of vernacular & ecological building materials & techniques.

Producing self sufficient energy & food.

Reduce, Reuse, Recycle

1. Indian GREEN compatible design 2. Appropriate green construction methods for specific locality and climatic conditions 3. Low carbon life-cycle of materials & building 4. Low waste in life-cycle of materials & building 5. Low toxicity, low ecological impact materials & products 6. EMF sensitive electrical design 7. Convenient recycling & composting facilities 8. Permaculture landscaping & gardens 9. Building site waste reduction/recycling systems & procedures 10. Design for deconstruction - recycling upon demolition ENERGY EFFICIENT DESIGN 1. 2. 3. 4. 5. 6. 7.

Superior performance of thermal envelope Optimum orientation & design features Passive heating Passive cooling Thermal mass Thermal chimneys Maximising natural ventilation and air circulation 8. Day-lighting 9. Zoning ACHIEVING CARBON NEUTRALITY (with CarboNZero) -

All the resources are used with care & economy, so the so house becomes a part of local system & Support its health & Sustainability.

Achieving sustainability

Source – Eco Affordable Housing, The journal of IIA may2010

1. Carbon life cycle analysis of building materials and construction process 2. Carbon measurement/monitoring and ongoing management 3. Off-setting carbon emissions, active participation in carbon markets 4. Verification and certification of carbon status

WATER CONSERVATION 1. 2. 3. 4. 5. 6. 7.

Rain water collection and use In-house grey water treatment & recycling Black water systems Low flow water appliances/fixtures Storm water and runoff control Green roof Permeable paving systems

ACHIEVING ZERO WASTE 1. Waste audits 2. Project management of sustainable infrastructure to prevent waste 3. Scoping study and evaluation of new technologies in waste minimisation 4. Drafting waste minimisation plans and ideas for discussion 5. Sourcing provision of special waste information and contacts R E N E WA B L E / TECHNOLOGIES 1. 2. 3. 4. 5. 6. 7. 8.



Smart-home automation systems Photovoltaic systems Wind power Micro Hydro Solar water systems LED & energy efficient lighting systems Heat reflective technologies for hot climates Sophisticated heat inverter technologies for heating & cooling 9. Bio-Diesel Fuel Generators

7. Sustainable Techniques to design passive strategies more scientifically & technically Passive Technologies – To increase sustainability various approaches to lower energy consumption are used in conjunction with natural building. Provision of thermal comfort & healthy environment in building, passively is an important consideration in the designing of buildings for efficiency, and well being of occupants & nature. In the earlier times building designers had to rely on natural ways & means for maximizing comfort inside the buildings. Today’s situation is that none of the measure resources viz. – land, money & time is available in abundance. This led us to design

Vegetation Control of solar radiation through glazings or openings

passive features more scientifically & technically. 7.1

Micro Climatic Analysis


Bio Climatic Chart


Temperature Gradient Graph


Heat Gain Calculations

Exterior window shading strategies

Types of Opening for day lighting & effective ventilation

Placement of weathershed according to Summer & Winter Sun

7. Sustainable Techniques to design passive strategies more scientifically & technically

7.1 Micro climatic analysis: Analysis drawing that illustrates the site’s solar geometry, wind patterns, and existing vegetation Microclimatic analysis is done by plotting grid on site & analyzing each cell of grid for its microclimate. It is essential to understand that the

7.2 Bio climatic Chart:

7.3 Temperature Gradient Graphs:

This graph gives information about the

This graph gives information about

passive design strategies which can be

temperature at any point within the wall

used in particular climate, by plotting dry


bulb temperature & RH values. This technique helps us to determine architectural responses that produces

climate of a region can be modified on a

thermal comfort in the particular climate

small scale within each site. If buildings


For material selection & fenestration design of building façade temperature gradient graphs are used.

are to relate properly to their environment they must be designed for the site and climate in which they exist.

Source – Carbon Neutral Project, the American Institute of Architects

Source – Thermal Environment & companion reference on climate

Source – Manual of Tropical Housing Design

Heat Gain in Building Envelope

7.Sustainable Techniques to design passive strategies more scientifically & technically

7.4 Heat Gain & Sizing of Openings:

By occupants

Internal Heat Gain

By Electric Lighting

External Heat Gain

By Electric Equipments

Thr’ Building Skin

Thr’ Glazing

Thr’ Infiltration

Sizing of Openings: Required size of openings can be obtained by plotting heat gain against wind speed

3 m/s

126 W/sq.m.

5.5% opening of floor area Source – Thermal Environment & companion reference on climate

Provision os sun shading according to sun position & season

Heat Gain Calculations External Heat Gain Internal Heat Gain 4.

Through Building Skin - The amount of heat that flow through the building skin due to temperature difference between “inside & outside”, is a function of magnitude of that difference, resistance to heat flow by the skin materials & the area of skin.


Through Glazing - The amount of solar radiations transmitted through the glazing is the function of available radiations, surface area of the glazing, orientation & heat transmission characteristics of the exposed skin.


By Infiltration - Infiltration heat loss or heat gain is obtained wherever the inside temperature of building is higher or lower than the outside temperature.

1. By occupancy - Metabolic energy of people can contribute too substantially to the amount of heat generated in the building. The heat generated depends upon the degree of physical activity of human being. 2.

By Electric lighting - The inevitable by product of electric lighting heat. The amount of heat generated by electric lighting is a function of illumination level & the efficiency of light source.


By Electric equipments - Electrical equipments & appliances operating in space contribute heat to that space. Amount of heat generated is a function of the kind of equipments used, the amount of equipment & how often it is operated.

The diagram shows the types of shading devices into fixed and movable. Movable shading devices may include awnings, hinged extensions and vegetation. If a mechanically dependent solution, the device needs to be designed for durability. February mid to October mid openings on east & west side

Sources of heat gain in building envelope

8. Natural Building

A natural building involves a range of building systems & materials that place major emphasis on sustainability. Ways of achieving sustainability through natural building focus on durability & use of renewable natural resources, such materials which in their original or recycled form produce healthy living environments & maintain indoor air quality.

Creating homes and buildings that are good for human health and for the planet is an essential part of sustainability. There are many Natural Building technologies in the world that are adaptable to the many climates and bioregions. Most of them rely on a few basic materials: earth, wood, and straw (where straw can be loosely defined to include any dried nonwoody plant material such as palm fronds, reeds, etc.). Depending on the climate these materials can be combined in any number of ways to make a natural home.

While dealing with natural building following points are taken into consideration,

Provision of thermal comfort & healthy environment in interiors is an important consideration in the designing of the buildings for efficiency & well being of occupants. The materials common to many types of natural building s are earth & bamboo.

? The

emphasis passive techniques through design

? The

operational & maintenance cost of the building

? The

orientation of building

? The

utilization of local climate & site conditions

? Vernacular

? Positive

& ecological construction materials & technologies

impact on the surrounding environment

? On

site energy acquisition

? On

site water capture

? Alternate

sewage treatment & water reuse

8.1 Natural Building Materials

Rammed Earth Construction, Earth is an ancient building material that has been used in many different ways around the world for thousand years. Building with earth materials can be way of helping the sustainable management of the earth’s resources. They can be put in place by using simple machinery & human energy. Earth buildings avoid deforestation & pollution and can achieve low energy costs throughout their life time (in initial manufacture & construction, in their use as home, and eventually their recycling back to earth) Rammed earth is a form of unbaked earth construction used primarily to build walls; other applications include floors, roofs & foundations. Rammed earth is formed by compacting moist sub soil inside temporary form work. Loose moist soil is placed in layers 100 – 150 mm deep & compacted. These walls are typically 300 – 450 mm thick. Row materials required for rammed earth construction – •

Soil – it is primary constitute of rammed earth. It should be

taken from subsoil found beneath organic & life sustaining topsoil. • Sand & Gravels – 45% - 80%, Silt contents – 10% - 30% • Clay contents – 5% - 20%, Plasticity index – 2 – 30 • Linear shrinkage – less than 5% • Organic contents – less than 2% • Soluble Salt contents – less than 2% • Water – the quality & quantity of water present has a very important influence on the overall quality of rammed earth. The water used should not contain excess organic matter •

&soluble salt. Additives – additives may be used to improve strength,

water resistance & shrinkage in rammed earth construction. Natural fibers such as straw are added in the rammed earth construction to overcome the defects. Straws from all main cereals (wheat, barley, rye, oats and maize)

8.1 Natural Building Materials

Bamboo Bamboo construction falls into the category of being environmentally friendly as the plants are extremely fast growing in comparison to trees. Bamboos have a high leaf surface area that makes it very efficient at removing carbon dioxide from the atmosphere and generating oxygen in its place.

Bamboo Construction Bamboo is one of the oldest and most versatile building materials with many applications in the field of construction. It is strong and lightweight and can often be used without processing or finishing. Bamboo constructions are easy to build, resilient to wind and even earthquake forces, and readily repairable in the event of damage. Bamboo is non-durable in its natural state. It provides a ready food source for insects and fungi, and can decay in less than a year in direct ground contact. Protection is therefore essential to ensure the longest possible life for the material, and the building in which it is used. Protection does not necessarily mean chemical treatment. The first line of defense is good design.

8.1 Natural Building Materials Adobe


Adobes are sun-dried mud bricks stacked with a mud mortar to create thick-walled structures.

Earthbags are soil-filled fabric sacks or tubes used to create walls and domes.



Cob is an ancient technique of building monolithic walls using "cobs" of moist earth and straw.

"Earthships" are the name for the independent living structures utilizing passive solar design and recycled materials

Compressed Earth Blocks

Light Straw-Clay

Compressed earth blocks are similar to adobes, with the main differences being they are not fully saturated with water

It is a German technique of ramming loose straw coated with a clay slip into forms as an infill for timber frame structures.

Hemp and other Fibers Thatch Hemp and other fiber-producing plants as kenaf and saw grass are currently being investigated as potential building products.

The use of reeds, grasses or palm fronds as a roofing material

Natural Plasters and Finishes.

Wattle and Daub

Before the advent of portland cement, most earthen and masonry structures were protected by mud- or lime-based plasters.

The technique of weaving branches (wattle) as a support for mud plaster (daub)

Straw Bale Construction

Wood Wood is an ideal building material: strong, easily worked and beautiful.

Straw-bale construction is a building method that uses bales of straw as structural elements, building insulation, or both.

Prithwe Agrihomes