Method of Waterproofing of Flat Roofs
Flat roofs can be made waterproof by utilising the following methods:
In the case of ordinary and cheap construction, the surface of the roof should be finished with cement mortar preferably in the ratio of 1:4.
Lime cream can be added to the finishing layer of mortar to resist the shrinkage and expansive impacts of cement concrete or mortar.
2. Asphalt Layer
In his method, Before laying a layer of mud or limo concrete, a layer of mastic asphalt is placed on the roof surface.
The asphalt layer is also sometimes placed on the top finished surface of the roof which is later sanded and finished.
3. Bedding Concrete and Flooring
The top surface of the R.C.C. slab is kept rough while casting. A layer of brick-bat lime concrete 1:2:4 about 100 mm thick or brick-bat cement concrete preferably in the ratio of 1:6:12 laid over the R.C.C slab.
This concrete layer is known as bedding concrete. The bedding concrete surface is then finished with tiles or other finishing materials.
Causes of Dampness into a Structure