How to install a damp proof course

Do you have damp patches on external or internal walls? Mould? Rotten floorboards? If you have an older property, you may need a damp proof course to prevent rising damp or penetrating damp.

A damp proof course is a physical barrier inserted horizontally or vertically to stop water from rising up through a wall (rising damp) or from passing outside to inside through the masonry (penetrating damp).

Building construction regulations require damp waterproofing to be installed 6 inches above ground level. This is a plastic membrane which acts to stop water rising up into the house. In the past a non porous course of stone was used but over time this can become broken or porous, allowing water to seep through.

New methods of damp proof injection mean that you can install damp control materials yourself if you have some knowledge of DIY. This involves drilling holes between 10 and 12 mm in diameter into your wall, blowing out the dust and injecting a chemical damp proof course which comes in the form of a cream. Over a few months a water repellent layer is formed and the wall above the damp proof course will dry out.

If you don’t want to do the job yourself, you’re best to use a professional like TDT preservation. This way you know that the materials used are covered by certificates issued by the British Board of Agrément and BSI. Professional damp proofers will also be able to identify the damp problem and apply the correct damp solutions. If a damp proof course isn’t identified and installed properly the problem will persist.


If you suspect you have some kind of damp problem, but aren’t sure how to fix it, then call TDT Preservation. Established in 1967 we’re professional damp specialists who can be relied on to identify the problem and provide damp solutions where necessary for your property. Our damp proofing experts (d.p.e) operate in Somerset and throughout the South West treating residential as well as commercial, public and national trust properties. Jump online and Book a Survey today or call us on 01761 416 728.

CALL TDT PRESERVATION – 01761 416 728 


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