Damp in Period & Heritage Properties
Older, solid-walled buildings manage moisture completely differently to modern cavity-walled homes. They were built to breathe – to absorb and release moisture through lime mortar, lime plaster and lime render. Most damp problems in period properties come from someone, at some point, sealing that breathability away with cement, gypsum or impermeable paint.
Our approach is to restore how the building was meant to work, rather than fight it with chemicals.
Looking for conventional damp proofing?
For chemical damp-proof course (DPC) injection, basement tanking and timber treatment on standard properties, our sister company Severn Damp Proofing handles that side of the work. This page is about the breathable approach for period and listed buildings.
Understanding Damp in Old Buildings
Not all damp is the same, and the wrong treatment can be worse than no treatment at all. We regularly see period properties where previous “damp proofing” – cement render, injected courses, gypsum plaster – has actually made things worse by trapping moisture inside solid walls.
Penetrating Damp Water entering through the building fabric – failed lime pointing, cracked or cement render, defective gutters. Often the most common cause of damp in old buildings, and very treatable once correctly diagnosed.
Trapped Moisture Walls that can no longer breathe because of cement, gypsum or modern paint. The cure is to remove the impermeable layers and reinstate breathable lime.
Rising Damp Genuine rising damp – moisture drawn up from the ground – is far less common than the damp-proofing industry suggests. In a period property it’s usually better resolved by restoring breathability and addressing ground levels and drainage than by injecting chemicals.
Our Breathable Approach
1. Proper Diagnosis We start with a thorough survey to understand what’s actually causing the problem – no guesswork, no rushing to sell you treatments you don’t need.
2. Address the Cause The best fix usually means tackling the real cause – lime repointing, replacing failed cement render, improving drainage and ventilation – not masking symptoms.
3. Restore Breathability We remove inappropriate cement and gypsum and reinstate breathable lime plaster and lime render, letting the wall manage moisture as it was designed to.
4. Make Good Re-plastering is done with breathable lime – never gypsum or cement-based products that simply trap moisture again.
Why Not Chemical Injection or Tanking?
In a modern house, an injected DPC or cementitious tanking can be the right answer – and that’s exactly what Severn Damp Proofing provides. But in a solid-walled period building these methods often trap moisture in the wall, pushing damp elsewhere and accelerating decay of historic fabric. For heritage buildings, breathable repairs are almost always the better long-term solution.
Free Damp Surveys
Not sure what’s causing damp in your period property? Contact us for a free initial survey. We’ll explain what we find and give honest advice on the best course of action – even if that’s doing very little.