Roof Waterproofing is a very important  to increase the life and strenght of the building. The surface of the roof faces the extreme weather conditions. This results in corrosion and development of cracks in terrace. In due course when rain water accumulates, water strats seeping inside the roof slab. over time deterioration of roof surafce will increase leading to more damage to the slabs.So it is very important to make concrete structure water tight, as concrete itself is not water tight.