Cost Effective Environment Friendly Construction Technologies

Housing, next to food and clothing is the most important need of a human being. The house reflects his/her socio-economic status in society. For most families, housing is perhaps a major goal of family saving effort. So it must be durable, as it is an outcome of a long drawn process of savings and aspirations.

Housing is a bundle of goods and services. It is not the product of uni-sectoral efforts. Housing production includes a multitude of tasks like land acquisition, development, laying infrastructure, site planning and architectural design on pre-conceived concepts of affordable densities, to provide for shelter, social and physical infrastructure, project finance and finally construction and delivery of the same.

It is within this context that a need was felt to look at ways of optimizing shelter cost. The usual practice involved in this area till the recent past has been to:

  1. Reduce area of the house to the minimum possible level
  2. Reduce the finishing specification of flooring, external and internal walls, fittings etc.

In last two to three decades, cost effective appropriate technologies have cross the borders of laboratory and research organizations and have reached real construction sites. Many experimental and demonstrative projects have been constructed across the country proving the strength and feasibility of these technologies.

A number of cost effective appropriate materials and technologies have been developed, standardized and are being used in the field with success over the years. Many of them have even proved themselves in the test of time. BIS has also included many of these technologies under their umbrella and are working towards covering the remaining so that minimum standardization is achieved and a standard specification for the same is evolved.

Some of the Cost effective appropriate Technologies are described in the table below

Building Component Alternative Systems
Foundations
  • Random rubble masonry in mud/cement mortar placed in excavation over thick sand bed. Rubble pointing above ground level in stabilized cement mortar.
  • Use of lean cement concrete mix 1:8:16 for base with brick masonry in 1:6 cement mortar footings.
  • Use of lean cement concrete mix as above for base and over burned bricks masonry in cement lime mortar (1:2:12) footings.
  • Arch foundations in place of spread foundations
Walls
  • Brick work in 1:6 cement mortar using bricks from black cotton and inferior soil stabilized with fly-ash.
  • Rat-trap bond brick work in 1:2:12 cement lime mortar/1:1.5:3 cement sand mortar.
  • Hollow concrete block masonry in cement mortar.
  • Compressed mud blocks masonry in mud mortar.
  • Stabilized mud blocks masonry (4% cement or lime) in stabilized mud mortar.
  • Sand lime brick walls in 1:6 cement mortar.
  • FAL-G sand block with 1:6 cement mortar.
Roofs
  • Domes and vaults in brick or stabilized mud block with appropriate mortar.
  • Upgraded thatch roof on appropriate frame work.
  • Pre-cast RCC ā€œLā€ panel
  • Precast RCC cored units in M15 concrete.
  • Precast RCC channel units in M15 concrete
  • Precast Waffle units in M15 concrete
  • Burnt clay tube roofing in vault form.
Roof/ intermediate slab
  • Filler slabs
  • Partly precast RCC planks and joist in M15 concrete.
  • Partly precast RCC joist and brick panels
  • Partly precast RCC in hollow concrete blocks
  • Thin RCC ribbed slabs
  • Ferrocement channels
  • Brick funicular shell on edge beam
  • Bamboo reinforced concrete
  • Brick funicular shells with RCC edge beams
  • Brick jack arched over RCC joist
  • Precast RCC cored units in M15 concrete.
  • Precast RCC channel units in M15 concrete
Spanning elements for openings
  • Brick arches : Flat, semi circular and segmented
  • Precast thin lintel and lintel cum chajja
  • Brick arch with sand stone chajja
  • Ferro cement chajjas

 

Door cum window frames
  • Precast RCC frames with wood insert
  • Resin bonded saw dust frame
  • Polyvinyl chloride frame
  • Fiber reinforced plastic frame
Door panels
  • Plantation timber styles with particle board inserts.
  • Medium density fiber board doors.
  • Cement bonded particle board
  • Plantation timber style with rice husk board inserts
  • Red mud polymer panel doors.
  • Ferrocement doors
  • Polyvinyl chloride doors panels.