There seems to be a lot of confusion amongst property owners concerning wall coatings that are waterproof and what the consequences are for breathability of the fabric of the building.

We are frequently asked by clients with penetrating damp if our range of coatings are “waterproof” and therefore able to prevent and indeed cure their damp problems. Any bespoke coating system will not be waterproof as this would effectively seal the outer wall and prevent the evaporation of moisture from the inside to the outside where it belongs.

Rather, our coatings are all “water resistant” in that they greatly reduce the amount of water the wall can absorb whilst still allowing the walls to breathe and release water vapour from inside to outside. Moisture and vapour move from hot to cold areas under the law of Thermal Dynamics and therefore the outer leaf of the wall has to absorb some degree of water in order to ensure the wall is colder than inside the house so moisture will move in the right direction.

The key to a quality coating is that it has to be water vapour permeable so as to avoid causing extra damp and internal mould through “condensation damp” which can be exacerbated by a non-breathable coating being applied on the outside. A similar unwanted effect can also occur if an already heavily painted external wall has a new coating applied straight on top without first breaking up and removing the majority of the paint from the wall before re-coating.

If you would like more information on selecting the correct coating or would like an unbiased report and visit to your property please CALL US NOW on 01908 516366 or email us via the CONTACT US button.

Examples of damp: