Phase 1A: Planning an earthquake-proof residential house to be build very quickly and cost-effective in Nepalese conditions by using naturally occurring material (completion of skeleton construction and roof in one week – May 2015)
The blueprints of the prototype house of Badri that will be build in Sudal, a small village 6 km east of Bhaktapur, will be the basis for the quantity determination of every single building material. This week we will remove the earthquake rubble from the site. Then we will commission an expert soil surveyor for the evaluation of stable ground for 12 foundations.
The roof pitch can be between 25 and 30 degree. This corresponds with the building culture and the existing residential buildings. Currently the dimensions are 25 degrees, a roof pitch up to 30 degrees can be planned individually and would have the advantage of more storage space.
The prototype won’t have a ceiling to reveal the roof construction from the inside, providing a better living climate. If desired the ceiling can be installed afterwards.
A first overview of the process and execution of the constructional work and details:
We will deliver all building materials with a small truck up to 200-300 m to the property. From here on the materials will have to be carried by as many helpers as possible to the site.
1. After the soil surveyor examined the site the ground can be excavated for the foundations (12 units).
2. Foundation shuttering will be installed according to site incline, around 50 cm in diameter each for the foundation parts above-ground.
3. Water, cement and sand has to be delivered to the site, the foundation concrete has to be mixed, poured and compressed into the ground or into the prepared foundation shuttering – again depending on the incline on site
4. Steel profiles in different lengths from 2,40 m to 5,50 m have to be delivered, the total weight is 1050 kg with bambus roof skeleton and 1850 kg with steel roof skeleton
5. In four sections the steel skeleton will be welded together, set up, connected to other steel profiles and reinforced with flat irons in a cross shape
6. Lateral metal sheets will be welded parallel to the longitudinal axes on the steel profiles to absorb forces created by the bamboo wall construction
7. Flat steel (5x50mm) will be welded from the outside on the steel profiles (around 32 welding spots) to reinforce the wall and ceiling
8. The skeleton construction has to be attached to the foundation with bolts, threaded rod with flat washer, nuts and concrete heavy-duty dowels. This includes the drilling of holes into the concrete foundation (two items each) and into the steel profiles
9. Wooden beams, planed, shielded under the roof ridge on one of the four steel beam axis (level of girder), fixed with brackets
10. Purlins, planed, have to be assembled in the angle of the roof pitch on the girder axis of the steel skeleton and the wooden posts with brackets and metal sheets. On the eaves side with 1 m roof overhang for the subsequent mounting of the bamboo rafters
11. Brackets (ca. 60×100 mm) have to be welded onto the steel construction and nailed on the wooden components, purlins and posts
12. Brackets (ca. 120×240 mm) have to be nailed on with wooden components, purlins and posts
13. Round steel (or threaded rods), ca 12 mm in diameter has to be delivered and drilled, screwed together and reinforced in three crosses into the roof construction with four posts
14. Bamboo rafters, ca 14 cm in diameter have to be installed every 50 cm on the reinforcing purlin construction, including 1 m roof overhang on the verge of the saddle roof
15. corrugated sheet panels for coverage of the bamboo rafters roof construction including ridge cap coverage on the joint of the metal sheets have to be screwed on, assuring the building’s watertightness. The outside walls will then be clasp with plastic canvas and the finishings on the interior can commence.