Bridging Damp

Bridging Damp

Rainwater damaged plaster should be replaced, salts can be left in the masonry from the rainwater that pull moisture from the air, this can cause a similar damp problem to appear on the plaster. Salts pulling moister from the air are termed Hygroscopic. When re-plastering a membrane is needed to separate the masonry from the plaster, this allows the plaster to dry quickly away from damp masonry and without any salts contaminating the new plaster from the masonry.

You get similar problem with concrete floors being raised up above the damp proof course where no damp proof membrane has been used beneath the original concrete and the new concrete layer is directly on top. Signs of bridging damp on plaster are similar to rising damp, normally bridging damp only travels 300mm up the wall at its wettest point then fades out quickly.

If you’re having problems with damp in your home call today to arrange a free damp survey on 07719 879751 or email: robert.w.j.smith@live.co.uk.

Treatment

The treatment involves the removal of the contaminated plaster that is bridging the damp proof course (DPC) and application of a membrane to bridge the damp proof course.

This membrane will separate the new plaster from the contaminated masonry protecting the plaster from ground salts and be a water proof barrier carrying plaster over the DPC. In most cases where floors have been raised above the damp proof course, a remedial damp proof course can be injected above the new floor level; a re-plastering process is also still needed because of ground salt contamination in plaster and masonry. We give professional long lasting guarantees on damp proof cause injection.

Injection

We use Wykamol Ultra Cure this is a silicone emulsion cream which is virtually odourless and low hazard. It can be used in all types of masonry and takes effect by migrating rapidly into the masonry pores reverting to a liquid to spread, polysiloxanes are formed this acts as the new DPC.