Penetrating Damp – What You Need to Know.
Penetrating damp is a more straightforward one to identify. Any water entering the building in ways in which it shouldn’t is classed as penetrating. A missing or cracked roof tile, defective guttering’s or down pipes, cracked or missing pointing or render, raised external ground levels, leaking windows, defective or slumped cavity wall insulation, slipped roof or chimney flashings, abutting walls, settlement cracks, and many more.
All the above, if left, or go unnoticed can lead to serious damage over time. Dry and wet rot can feed off these and wreak havoc in a building leading to costly repairs. A thorough survey could save you thousands of pounds. Identifying these issues takes a trained and experienced eye, some are almost impossible to spot and what is known in the trade as an invasive survey is often required. This could mean cutting and making a trap to access the sub-floor, opening up the cavity wall to insert a camera, taking plaster samples to establish the moisture content at varying levels and to test for salts, removing skirting boards to check for bridging plasterworks, or architraves to look for dry rot etc. The earlier these issues are addressed the lower the cost of remedial action is usually the case. It could be something as simple as replacing a gutter joint or repointing a flashing and could save you thousands of pounds in the long term.
An experienced surveyor is essential so that nothing is missed.
Penetrating Damp Explained: Causes and Solutions
What is penetrating damp?
Penetrating damp occurs when water enters a building through defects such as cracked roof tiles, faulty gutters, damaged pointing, or raised ground levels.
How can I tell if my property has penetrating damp?
Common signs include damp patches on walls, peeling paint, mold growth, musty odors, and sometimes visible water ingress after heavy rain.
Why is an invasive survey sometimes necessary?
Some sources of penetrating damp are hidden and difficult to detect. Invasive surveys—like opening walls or inspecting sub-floor areas—help identify the exact cause.
What damage can penetrating damp cause if left untreated?
Penetrating damp can cause a multitude of problems from spoiled decorations, damaged plasterwork, wet and dry rot, and can lead to structural damage to masonry and timber work. The earlier it’s identified and repaired the better.
How can penetrating damp be fixed?
Repairs depend on the cause but may include replacing roof tiles, fixing gutters, repointing brickwork, improving drainage, or treating timber affected by rot.
