Diagnosing the causes of dampness (GR 5 revised)
BRE (Building Research Establishment) is an independent, research-based consultancy, testing and training organisation, operating in the built environment and associated industries.
Diagnosing the causes of dampness (GR 5 revised) was written by John Houston and published by BRE on 18 March 2015.
Even in a ‘dry’ building, there is a surprising amount of water in porous materials, most of which does no harm. A building is only considered to be 'damp' if the moisture or its effects become visible, leading to deterioration in decorations or the fabric of the building.
Dampness is the most common problem in housing. It results in visible wetting of walls, ceilings and floors, blistering paint, bulging plaster, sulfate attack on brickwork and mould growth on surfaces and fabrics, usually accompanied by a musty smell. It can also lead to less obvious problems such as a reduction in the effectiveness of thermal insulation or cracks in brickwork due to the corrosion of embedded metal components.
The first step in solving damp-related problem is to diagnose the cause.
This Good Repair Guide provides advice on how to identify the potential causes of dampness in homes. It is aimed at housing professionals, home owners and occupiers, and replaces guidance published in 1997.
Its contents are:
- Introduction.
- Internal dampness: moisture from condensation.
- External dampness: rain penetration.
- External dampness: rising damp.
- Construction moisture.
- Leaking pipes.
- Leaking roofs.
- Spillage.
- Ground and surface water.
- Contaminating salts.
- Hidden dampness.
- Specialist inspection.
- References.
Other guides in the series, Good Repair Guides 6–8, cover specific remedial treatment for the principal causes of dampness.
[edit] Related articles on Designing Buildings Wiki
- Assessing moisture in porous building materials.
- BRE articles on Designing Buildings Wiki.
- BRE Buzz articles on Designing Buildings Wiki.
- BRE Buzz.
- BREEAM.
- Building damp-free cavity walls.
- Building Research Establishment.
- Condensation.
- Damp in buildings.
- Damp proof membrane.
- Damp proofing.
- Damp-proof course.
- Dew point.
- Dry rot fungus.
- Efflorescence.
- Humidity.
- Interstitial condensation.
- Penetrating damp.
- Rising damp in walls - diagnosis and treatment (DG 245).
- Rising damp.
- Spalling.
- Understanding dampness.
- Wall insulation and moisture risk.
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
New and updated CLC building safety guidance.
New UK National Buildings Database.
Building Safety Wiki Interviews
Chief executive of the British Woodworking Federation.
Planning condition discharge in England and Wales
A brief explanation from a building compliance expert, with further links.
Overheating guidance and tools for building designers
Guidance for dealing with element of building fabric control that have increasing importance.
Shading for housing, a design guide
From the Good Homes Alliance and British Blind and Shutter Association.
UK Standard Skills Classification (SSC)
A shared framework for describing skills needs.
Social media ban consultation comes to close
CIOB urges UK Government to consider social media’s role in careers guidance in ban debate.
The latest of eight Skills England apprenticeship units
The addition of battery manufacturing welcomed by ECA with a warning about the risks of fast-tracked apprenticeship units.
Building Control Independent Panel final report
A precis of a key report led by Dame Hackitt with full recommendations and link to the government response.
Building Safety recap April, 2026
A short and longer run-through of the month, with links to further information and sources.

















