Causes and precautions for dampness in walls.

If the foundation masonry is directly exposed to sub-soil water, the water may enter the building through the walls.

For this, ensure the pointing or plastering to the exposed walls is done to restrict the direct contact of sub-soil water with foundation masonry.

Generally, the parapet masonry and the top floor masonry of the external walls are the worst affected by the direct rains.

During the masonry of such walls, ensure that quality masonry using rich mortar with waterproofing compound is done.

The hollow spaces and gaps should not remain in this masonry as these are the routes for the water to enter.

Plaster these walls with rich cement mortar containing water-proofing compound.

Uninterrupted curing should be done to this plaster for avoiding formation of any cracks.

For the junctions of R.C.C. and masonry, chicken mesh should be used before plastering.

The terrace slab of the building should be projected 0.6m beyond the building line, all along its periphery. This projection saves the top most masonry of the wall from direct rainfall and reduces the chances of the dampness.

Dampness due to rain may occur on the wall, in the form of small or big circular spots. It is often observed that these spots are the locations where holes are made for the scaffolding of the external plastering and which are not treated properly afterwards. Avoid such holes as far as possible and insist on M.S. scaffolding for the plastering from outside.

Dampness is also observed on the ceiling in the form of patches.

It is due to the stagnant water on the terrace or some organic material dumped on terrace.

Ensure that during the execution of the terrace waterproofing work, a proper slope should be maintained, so that water does accumulate at any place.

Keep the terrace clean during the rainy season to prevent continuous dampness due to the presence of organic materials.

The terrace slab concrete of the building should be cast carefully so that it attains density and impermeability.

Possibility of any leakages through such dense concrete is almost nil.