Flooring for low cost rural housing

A common low-cost rural flooring in Nepal is the mud (earthen) floor with cow-dung/clay finishing, and an improved version is a brick-on-edge or cement-stabilised floor. The mud floor is explained here.

Construction of mud floor

1. Site preparation: remove the top soil, vegetation and loose earth from the floor area. Set the floor level at least 300-450 mm above the surrounding ground.
2. Filling: fill with good, clean soil in layers of 100-150 mm, with a bit of water, and ram it until firm.
3. Base layer: spread a 75-100 mm layer of well-mixed clay, sand and chopped straw (or cement-stabilised soil with 5-8% cement), and ram it.
4. Surface coat: a 10-12 mm coat of fine clay mixed with cow dung (or red clay, geru) is spread and smoothed with a wooden float.
5. Curing: keep it shaded and damp for several days, then let it dry slowly.
6. Maintenance: regular re-plastering with cow-dung, clay and water, usually every few days or weeks.

   cow dung + clay coat   (10-12 mm)
   clay + sand + straw    (75-100 mm)
   rammed earth fill      (layers of 150)
   original ground        //////////////

Precautions for durability

• Select well-graded, non-expansive, organic-free soil.
• Raise the plinth and provide drainage and a gentle slope away from the walls.
• Protect against rainwater with wide roof eaves and a plinth protection (apron).
• Ram thoroughly and avoid cracks; cure slowly.
• Add 5-8% cement or lime to stabilise.
• Re-plaster regularly with cow dung to seal cracks; keep termites away with treatment.