- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 16 Jun 2018
Diagnosing the causes of dampness (GR 5 revised)
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:
- Internal dampness: moisture from condensation.
- External dampness: rain penetration.
- External dampness: rising damp.
- Construction moisture.
- Leaking pipes.
- Leaking roofs.
- Ground and surface water.
- Contaminating salts.
- Hidden dampness.
- Specialist inspection.
 Find out more.
 Related articles on Designing Buildings Wiki
- BRE articles on Designing Buildings Wiki.
- BRE Buzz articles on Designing Buildings Wiki.
- BRE Buzz.
- Building damp-free cavity walls.
- Building Research Establishment.
- Damp in buildings.
- Damp proof membrane.
- Damp proofing.
- Damp-proof course.
- Dew point.
- Dry rot fungus.
- Interstitial condensation.
- Penetrating damp.
- Rising damp in walls - diagnosis and treatment (DG 245).
- Rising damp.
- Understanding dampness.
- Wall insulation and moisture risk.
Featured articles and news
Wall covering used to insulate rooms and fight against rising damp.
New eligibility criteria for EU nationals explained.
Click and lock flooring.
Recovery Advice for Business scheme launches.
Insight paper examines nuclear and net zero goals.
Suburban Americana with a secret past.
New planning rules to protect theatres, concert halls and music venues.
Public engagement in London Borough of Enfield's heritage strategy.
Engineering services in the spotlight.
The Government's Summer 2020 economic update.
Getting organised below the surface.
Securing suitable water systems.