Prefab bamboo and earth house

BAMBOO HOUSE

00 The bamboo house is built at Auroville bamboo land premises in march of 2016, as a part of intensive bamboo construction workshop. This house can be used as a semi permanent housing unit in tropical climate.

GENERAL INFORMATION TECHNIQUES/MATERIALS The Pre-fab Bamboo house is designed as semi-permanent cost affordable house with eco-friendly materials like bamboo and earth.The house is divided in four main elements and those elements are the reason it makes a prefabricated house and easy to move from one place to another. The House is resting on 0.3 x 0.3 m concrete footing raised 0.45 m above ground lvl. with floor truss made of bamboo.

The wall panels are of bamboo frame with wattle and daub technique. The wattle is interwoven bamboo splits and Mud along with coconut choir, sand, cement as a stabilizer and lime mixed together to form the daub. The plastering with daub was done once the wall panels were fixed on site. The Floors are made of Coconut wood inside and in the verandah split bamboos are used as flooring materials. The Roof is made up of Trusses from bamboo, prefabricated and placed later on site once the wall panels were fixed. The roof covering was done with coconut leaves (Keeth) and later covered with green mesh.

Note: The roof pitch turned out to be not high enough for keeth roof to drain of water and hence covered with plastic sheet and green mesh cover at the end. one pitch roof in north and south need to be added to prevent windy rain coming at an angle.

01

Location Bamboo land, Kotakarai, Auroville

Auroville Bamboo land is located on the outer reaches of Auroville’s greenbelt, is dedicated to experimentation with agricultural bamboo and intercrop relations. At Auroville Bamboo land, the Bamboo Centre will develop and refine methods for effective bamboo production, as well as completing Auroville Bamboo Centre’s vision to encompass the full cycle of bamboo, from seed to final product. Auroville Bamboo land is designed to be a model for utilizing bamboo in intercrop plantations, the first of its kind in Tamil Nadu.

[ INTRODUCTION] 11

LAKE

1: Fruit & tree plantations 2: Bamboo intercrop plantation/sectum 3: Natural growth (Sacred grooves) 4: Bamboo nursery 5:Cowshed 6: Chicken barn 7: Water tank 8: Watchman’s hut 9: Youth & children art space 10: Volunteer hut + kitchen 11: Site_bamboo house Figue 1: site map_bamboo land

02

Basic plan The bamboo house is designed to have advantage of maximum light and ventilation and is oriented in north south axis.

Area: 6.5 x 4.5 mts 30 sq mts approx spaces: - verandah (6.75 sq mts) - living room + kitchen (18 sqmts) - bed room (11.25 sq mts) - bathroom + toilet separate (4 sqmts)

[

]

DESIGN

2.00

2.00

1.50

4

6

8

1.76

1.42

0.92

1.84

0.40

5

1.50

11

1.42

1.58

0.78

15

1.54

4.50

1.90

1.84

bed room 1.42

1.76

2.00 6.50 Figue 2: Plan_@ 2.4 mts

1.50

0.84

13

7

2.00

10

3

1.50

living + dining

1.00

3.00

0.86

kitchen

2.92

14

1.54

verandah

0.30

2.50

3.00

0.50

DESIGN

1.62

[

0.90

4.55

03

South elevation

]

0.30

0.60

1.50

0.74

2.50

3.00

4.55

04

North elevation

[ DESIGN

]

0.30

0.30

0.60

1.50

1.55

4.55

0.50

05

East elevation

[ DESIGN

]

0.30

0.30

0.60

1.50

4.55

DESIGN

0.50

[

1.55

06

West elevation

]

07

Toilet & Bathroom

Plan

shower

0,8

1.80

1.10

0,8

1.30

1.60

Toilet

1.70

1.15

1.70 2.85

] 0,3

Section

0,45

2,33

DESIGN

0,55

[

PLAN

G.L

08

PROCESS The bamboo house is divided in 4 entities, footings & columns, floor truss, wall panels and roof truss,which are constructed seperately and assembled later on site.

figure 3 : placing culmns on the footing

figure 4 : bamboo culm (bolted) resting on the footing

0.30

bamboo culm (0.08 mts) opening to put concrete slurry in the culm 8 mm Ă˜ steel rod

Footings & Columns 0.50

nut and bolt 8 mm Ă˜

0.45

0.30

The superstructure is standing on a 0.3x0.3x0.45 M. footings with two 8 mm. steel rebars projecting 50 cm. inside the culms. Fastner (?) were used to tie bamboo columns together. The bamboo culms are then fixed with nut and bolt. reinforced with 1:1cement aggregate mortar.

0.3x0.3x0.45 mt footing 5 cm cement bed

figure 5 : foundation detail

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PREFABRICATION OF CONSTRUCTION ELEMENTS

] Floor Truss

Floor truss were one of the other entity, designed to support the floor. The house has in total 6 trusses, 5 of them being 4.5 mts wide and one is 3mts wide. Horizontal member are joined to the vertical culms with fish mouth and bolted. An arch is introduced below the horizontal culm to divide the load evenly. figure 6 : bolting the floor truss with the columns

figure 7 : one of the floor truss under construction

bamboo pegs to reinforce the tie

0.52

fish mouth joinery angled fish mouth joinery

bamboo culm arched to divide the load

4.39

4.50

figure 8 : floor truss detail

09 wall panels

The wall panel frames are simply made with 4 bamboo culms joined together with fish mouth joinery technique, as shown in fig:8. The dowels for the joinery are reinforced with glue, so the the whole frame is then tied with belt fastener to reinforce the joint.

figue 9 : constructing frames of wall panels

Wall panels are basic prefab module which we make at bamboo center, However this house has wall panels of different sizes in terms of width. the height was fixed at 2.4 mts with 0.5 mts of opening. solid bamboos are used as grills and later the opening is protected with wiremesh for mosquito net. figue 10 : view of wall panels after assembly

[

PREFABRICATION OF CONSTRUCTION ELEMENTS

]

1.42

0.50

solid bamboo pegs to reinforce the fish mouth

bamboo splits interweaved to make wattle for the wall panel

1.98

2.10

solid bamboo pieces used to make grills for the window, later the opening is covered with wire mesh to prevent insects and mosquitoes

wattle (with interwoven bamboo splits) & daub (mixtue of red earth soil, sand,cement,coconut shell fibre)

drilling hole for nuts & bolts 30 cm from top & bottom and 1 in middle figue 11 : wall panel_detail

10 wall panels_wattle & daub

figue 12 : mixing of the recipe for wattle & daubl

figue 13 : applying the recipe on the wattle of the wall panel

[

figue 14 : finished wattle & daub panel

PREFABRICATION OF CONSTRUCTION ELEMENTS

figue 15 : red earth soil

figue 16 : fine sand

figue 17 : cement

figue 18 : coconut shell fibre

Wattle & daub is one of the oldest wall construction technique. It is divided in two parts as the name suggests. wattle which is the skeleton of the wall is made here through the bamboo split strips, interwoven. (refer fig: 12 ). daub is a recipe prepared with the local red earth soil,fine grained sand, cement and cocunut shell fibre to bind the recipe together.

]

11 roof truss

figue 19 : making of roof truss

[

PREFABRICATION OF CONSTRUCTION ELEMENTS

]

roof truss was the last set piece in the house which was assembeld before the wall panel for convienience. all the joineries are angular fish mouth, nailed, bolted and reinforced with the 2 cm plywood gusset plate

bamboo pegs (dowel) to reinforce fish mouth bamboo post joined with angeled-fish mouth joint

4.47 2

3.0

44

1.40

gusset plate (plywood) bolted with the truss pieces 5

2 1.

1.

offset cut out for the purlin to rest. the rest of the purlins are tied with lashing technique

6.86

figue 20 : roof truss details

12 Keeth roof

The existing roofing material used is keeth (interwoven coconut leaves) for insulation.

There is a layer of water proof tarp on top with the final finish of green mesh cover.

green mesh water proof tarpaulin sheet

Keeth cover (interwoven coconut leaves)

[

option I Keeth water proof tarpaulin sheet Green mesh cover

ROOFING MATERIALS

length

width

]

thickness

-

-

-

11

11

-

ridge (aluminium)

25,000

cost/running feet

option II corugated aluminium sheet roof cover

total cost (Rs)

5.5

1

4.5 mm 3 mm

118 850/2.5 mts

23,600 3400

13

figue 21 : Views of house

figue 22 : View of the house North-East

15

figue 23 : Views of the house

figue 24 : View of the house after plastering. North-East

17

[

D e s i g n e r, A r c h i t e c t : Suraj Dwivedi Workshop co-ordination: Nils lalleike Suraj Dwivedi Walter Van Assche

]