Waterproofing treatment of concrete is an essential part of building construction. In case of multi-storey building, besides waterproofing, thermal insulation is an equally important factor to be kept in consideration. This is achieved by increasing the thickness of grading by using economical and effective materials.
The waterproofing treatment is generally given to roof of multi-storey buildings and other important structures may be divided into the following steps:
- Painting the top of roof slab uniformly with the layer of hot bitumen spread at the rate of 1.70 of bitumen per sq.m of the roof surface.
- Spreading immediately course and at the rate of 0.6 cu.m of sand per 100 sq.m of roof surface when the bitumen it still hot.
- Laying cinder concrete 1:15 (1cement:5 cinders of 13 mm and down gauge) in an average thickness of 15 cm, the slope for the proper drainage of the roof being given to this layer.
- Lying 7.6 cm thick layer of lime concrete over the consolidated layer of cinder concrete, the lime concrete being prepared by mixing 50% of mortar consisting of lime and sand mixed in the ratio of 1:2 with brick blast 25 mm, and down gauge.
- Spreading 13 mm thick layer of cement mortar 1:3 and laying title brick flat and open jointed over the mortar. Finally grouting the joints in the bricks with cement mortar 1:3.
