WHAT IS LATERAL DAMP?
Lateral Damp is moisture driving itself directly through the wall. That can happen through a poorly painted wall with cracks or through crevices around windows and doors.
CAUSES OF LATERAL DAMP.
P V A consists of 50% water. Once it is applied to the wall, the water evaporates leaving a very thin film on the wall, P.V.A. does not use an acrylic based resin (Acrylic based resins are permeable to moisture therefore allowing evaporation to drop of water) P.V.A. is water proof, but because it is so damp it soon cracks and allows drops of water to enter the wall. Ines drops are then trapped behind the thin P.V.A. film. The salts in the water then react with the minerals in he plaster causing damage to the plaster. Once the plaster starts becoming damaged the cracks widen With lager cracks more water can enter the wall and if the house is not built with a cavity walls, thus moisture will penetrate right through the wall and cause the need for damp repairs on the inside.
Water entering the wall through crevices around windows and doors is obviously caused by a poor seal in these areas when the house was built, or no seal installed at all. Plaster deterioration could also be developing in these damp areas which would then cause larger cracks and more water to enter the wail.
SOLUTION TO LATERAL DAMP REPAIR.
The solution is to apply an acrylic based coating system which will allow wails to breathe but is waterproof and thick enough to expand and contract, with your walls.
Lateral damp through cracks at windows and doors is sealed by an industrial silicon building sealant. If in the case of a damaged plaster crack we will remove the damaged plaster and re-plaster with a water proof screed in the plaster.