Above grade water proofing

Water proofing of surface above grade is the prevention of water instruction into exposed element of a structure or it component. Above grade material are not subjected to hydro static pressure but exposed to determination weathering effect such as ultraviolet light.

Requirement

They must be breathable to prevent liquid from seeping into the space but allow water inside the wall to escape because the membranes will be exposed to light it must be UV resistance. It must be resist to abrasion and corrosion because they are often used where there is high volume of foot or vertical traffic. It may be applied as horizontal surface like roof balcony and parking dock and vertical surface such as wall.

Below grade water proofing

Water is rest exist pressure I.e hydro static pressure when it rains and the water table rises pressure increase and ground water table rises pressure increase and ground water publish the foundation in all direction spreading into naturally occurrencecrack and fracture determine the foundation and eventuality reaching the interior and seepage of dampness.

Difference between above grade and below grade water proofing