It was conscious decision to build with materials which that are ecologically sensitive and available locally, reducing the transportation cost. The primary material used is unbaked mud bricks. The bricks are used to erect the walls and create Nubian vaults as the roof system. Through that process we were able to avoid the use of any steel, cement and wood. The only wood that is used is the rose wood for making doors and louvres. Mud mortar is used as the main binder. We would also like to use lime plaster as an alternative as it provides better protection during monsoon.
Another primary building material is Bamboo. It is used to create a canopy over the courtyard. All the Posts, rafters, purlins and the roof are made of Bamboo. It also allowed us to have a wider span as compared to wood along with a better shear strength. Bamboo can also be harvested in a shorter period of time compared to wood. As it is endangered in the region, we can grow more bamboo on site. This helps us to further reduce the carbon footprint as the energy required to produce Mud bricks and Bamboo is minimal. We have opted for Laterite Stone foundation to reduce the use of cement. Used broken tiles are employed as the flooring which protects against water seepage.
The building is oriented with its longer length running along the East to West direction to get maximum light in the courtyard. The 600mm thick walls protect from heat gain, hence keeping inside climate cooler. The dormitories are placed on the east side with brick jaalis to get in the morning sunlight as a means to wake up the children naturally. Spaces like the admin area, and meeting room are located on the West side. As storage would be the least inhabited area, it is located in the South West side as it will tend to heat up the most. It also has brick jaalis for air flow to maintain the quality of the nutritional materials. The seating at the entrance on the south covered with bamboo shade is a threshold between inside and outside of the building. It is recessed inside to avoid direct southern sunlight which is cut by the protruding bamboo roof.
Water from the bamboo gutters on the roof will be collected into a water body placed near the entrance and at the contemplation area. The average rainfall of the region is about 1100mm per year which could be used for creating a pond and for water harvesting to help during the dry season. The pond placed at the entrance also helps cool the hot and dry winds before entering the courtyard which will help create a microclimate inside the building. The outdoor play area is located on the North side of the building to get maximum shading from the structure. The threshold between the courtyard and outdoor spaces has wooden double hinged doors that can be opened and gives feeling of expanse. The double hinged doors also have louvers to let the natural light and air flow through the building while the doors are closed. Which further helps in creating a micro climate.
The courtyard is shaded using three bamboo posts connected by lashing to form a column. The Beam are of four bamboo pieces forming 2 lateral double rafter beams. On which a set of purlins rest at every meter. These joints are made stronger using fish mouth cuts, bamboo dowels and lashing. The roof is made using half cut bamboos, placed inverted alternatively which is an efficient and cost-effective method. The roof has a 2-degree slope with a gutter running at the end which collects water.
The Nubian vault technique uses locally and widely available resource, mud. The loadbearing walls are of 600 mm thickness made of unbaked mud bricks. These have 90mm wide openings for jaali. The doors have arched openings which remove the need for lintels. The technique of Nubian vaults will be employed to build the roof using small and lightweight unbaked mud bricks and mud mortar. The vault does not require formwork. A steel wire is attached at the centre of the vault with a cord. That cord acts a guide to place the bricks. The vault bricks are laid at a 60 degree angle to make the primary brick rest on the wall and successive bricks on the preceding. The desired curve is an ellipse and not a perfect semi circle to increase its compressive strength. The wall buttresses offer support to the vaults. An infill between the vaults will be done to reduce slope and erosion during rains. It is then covered by a plastic sheet for waterproofing and a layer of mortar on top. Water is drained using bamboo gutters fitted at the height of the infill. The walls are plastered by using mud/lime plaster.
01. EARTH
02. BAMBOO COLUMN IN ROCK FOUNDATION
03. LINEAR BAMBOO COLUMN OF 3 BAMBOO POSTS
04. LATERAL DOUBLE RAFTER BAMBOO BEAM
05. BAMBOO PURLINS
06. HALF CUT BAMBOO PROFILE ROOF WITH 2 DEGREE SLOPE
07. ROCK FOUNDATION / CONCRETE PLINTH BEAM
08. LOADBEARING MUD BRICK WALL 600MM THK.
09. MUD / LIME PLASTER
10. BUTTRESS FOR SUPPORT
11. PLASTIC SHEET FOR WATER PROOFING
12. INFILL WITH BRICKS AND MORTAR TO REDUCE SLOPE AND AVOID EROSION
13. BAMBOO GUTTER
14. EXTRA BRICK COURSE ON FACADE WALLS
15. NUBIAN VAULT WITH THIN UNBAKED MUD BRICKS
16. CONCRETE SLAB WITH BROKEN TILE FLOORING
17. WOODEN LOUVERED DOOR
