Step 2: Imepede/Stop

This is where the method of repair is done on the negative side, the water OUT. In some circumstances, it is not possible to rectify the root cause of leakage due high cost of repair from the source of leakage or due to unknown cause (which is very slim). This is a temporary solution.

Lower Level ceiling with upper level that has swimming pool, walkway, garden, playground, ect on top of them will have waterproofing failure due to wear and tear and life span of waterproofing material.

It will be very costly to have the whole swimming pool to be re-waterproofing when there is a cracked line that cause the leakage found on lower level ceiling. A cost effective PU grouting may used to temporary stopping the leakage.

PU grouting

In market pratice, pressure PU grouting is used, chemical is injected into the affected ceiling; normally cracked line with water droplets or formation of efflorescence with water droplets. PU grouting only work on concrete with water moisture within them; the chemical will only react with water substance. It required pressure to inject into the affected area.

Using PU grouting to stop water from the negative side can only be apply to waterproofing failure. It will not work for water supply pipe leakage, instead it will worsen when the source is not being rectified. When PU is apply to water seepage from lower unit ceiling, it stop water from leaking out from the affected area.

The water from the source will keep increasing to water OUT which has being stop will lead to water accumulated inside slab. Water inside the object will need to drain out somewhere. When water leakage is stop via PU grouting, water may force to leak out from other area.

Water bubbles could be seen on part of external wall due to painting which is waterproof. This could happen if there is leakage inside the building where water is being forces out. Likely case, could be water supply leakage, groove line, expansion joint and etc.