External sealing of foundations or retaining walls is necessary to protect each building against water. These substrates are constantly exposed to moisture, which can lead to serious damage to the building structure. Leakage may also be associated with groundwater level variability. Avoiding this problem is possible by using foundation waterproofing or external waterproofing in a basement based on a bituminous system – products S 700 (N 500), N 300 or a polyurethane-bituminous system based on the use of N 1000 membrane. It will permanently and tightly protect these surfaces . These products are resistant to large temperature changes or moisture penetration, which is confirmed by numerous tests carried out in certified units throughout Europe.