Penetrating damp can have a number of different causes, when above ground level it is usually because of leaking gutters or down pipes, defective flashings, masonry and mortar defects and poor ventilation. It is treated by removal of all plaster and backing coats in the affected areas, applying a waterproof sand and cent render and finished with a plaster topcoat.
Basements areas and retaining walls are particularly prone to penetrating damp due to increased water pressures at sub-ground levels. In most cases below ground moisture will penetrate through up to ground level, therefore all plaster and backing coats will need to be removed up to the DPC level and treated for moisture ingress.
Cementious Tanking system; involve applying two coats of waterproof sand and cement render onto prepared brickwork or block work. Then applying a Cementious waterproof tanking mix over the render followed with a further coat of waterproof render. When dry the area can be finished with plaster if necessary.
Cavity drain membranes ; provide an alternative to conventional cementitious tanking systems, which work by holding the water back. Cavity drain membranes work on the principle of allowing water to continue to penetrate the structure but control it in the air gap and divert it to a suitable drainage point. They do not allow pressure to build up against the internal construction and the air gap behind the membrane allows the structure to breath and to some extent to dry out. The membranes are losing laid on floors and fixed to walls using special plugs and sealing materials, with little or no preparation required to the substrate. Once the membrane has been fitted, wall surfaces can be dry lined or plastered directly and floors can be screeded or a floating dry board system installed.
| For a free survey contact us today
on: Unit 55 Culvert Court, London SW11 5AU |
075 9350 6106 020 7498 4786 |
