Penetrating Damp

What is Penetrating Damp?

Penetrating damp is moisture that enters a building through the roof or external walls, which is different to rising damp, which comes from the ground. Years of driving rain can cause brickwork, masonry and render to decay and that can lead to moisture penetrating the material and causing damage to the internal walls and timber frames.

Leaking Roof

A major cause of penetrating damp is a leaking roof, which might be due to missing or dislodged roof tiles; another cause is blocked or damaged guttering that can lead to rainwater running down the external walls. Once rainwater enters the internal roof structure, it will damage joists and rafters and mould is likely to follow and if unaddressed, considerable damage will be the result.

Compromised External Walls

Whether brickwork, masonry or render, external surfaces have to endure the harsh British climate and that can lead to degeneration and moisture penetrates into the internal structure. You should closely inspect the external walls, looking for crumbling materials and moss growth, both of which are signs of moisture retention.

Timber Window & Door Frames

Timber frames are affixed to brickwork and usually have a mastic seal to prevent water from penetrating into the interior; this seal needs to be inspected on a regular basis and any breach should be repaired promptly. Check the interior window reveals for signs of damp and don’t forget to also look under the window board.

Tell-Tale Signs of Penetrating Damp

Signs of penetrating damp include the following:

• Damp patches on internal walls that remain damp
• Damaged plaster and bubbling paint
• Evidence of timber rot
• Salt stains on walls
• Rotting skirting and architrave
• Mould and mildew on hard surfaces
• Musky smell in the house
• Moss growth on external walls

If you should notice any of the above signs, you should contact London Damp Specialists and book an independent damp survey by a PCA-certified surveyor. This is the best way to get an accurate assessment of the damp issues in your property, plus you receive a quote from the best damp-proofing company in London, an organisation that issues a 30-year guarantee on all their work.

The Importance of Correct Diagnosis

It is very easy to misdiagnose penetrating damp and that can lead to wasted money on ineffective repairs. Removing damaged plaster and recovering the affected area is not likely to be effective if the root cause of the damp is not addressed.

How Best to Treat Penetrating Damp?

Penetrating damp is a serious threat to London homes and with more than 40 years of hands-on experience treating damp and mould issues, we have all the solutions, which might include:

• Cavity wall injectables
• Waterproof renders
• Water-repellent paints & coatings
• Silicone sealants for roofing
• Unblocking guttering
• Sealing exterior walls in transparent coatings
• Replacing damaged roof tiles

The best treatment is determined after an inspection by a PCA-certified damp surveyor and no obligation quote along with a comprehensive 30-year guarantee on everything we do. Penetrating damp is a complex problem that might require numerous treatments to ensure that damp will not return. The problem is that penetrating damp is not normally apparent until considerable damage is caused, which is one good reason to have regular damp inspections that give you early detection.

If the correct treatment is not carried out, the chances are that the damp will reappear and that means expensive and repeated repairs. Remedial work should not be undertaken until the root cause is established, only then can you move forward with some confidence.

If you are planning to purchase a property in London and you are concerned about penetrating damp, we recommend booking our homebuyer damp survey, which is a thorough and detailed inspection that would reveal any damp, mould or timber rot issues.

Many London homeowners are looking to check their home prior to the arrival of the cold winter months, which is the best time to undertake a professional damp survey.

Call London Damp Specialists on 020 8242 9391 or complete the online booking form and let a PCA-certified surveyor inspect the property, looking for any signs of penetrating damp and other moisture issues.