Penetrating Damp

The Dangers of Penetrating Damp

Rainwater entering a building through the roof or exterior walls is called penetrating damp; masonry and brickwork have to endure harsh weather conditions, with driving rain and gale-force winds and should your London home fall victim to penetrating damp, you need to take immediate action to limit the damage. The damp UK climate is an ideal breeding ground for penetrating damp and with increased rainfall, London is wetter than ever, which is not good news for homeowners.

We have been providing industry-standard damp surveys for London homeowners for 40 years, a family-managed business that offers independent damp inspections by qualified damp specialists and sourcing the causes of penetrating damp is one of our specialities.

The Damp London Climate

London sits on the Thames Valley Basin, a large area with a clay-based foundation and that means moisture retention. Heavy rainfall is a prime cause of penetrating damp; a leaking roof or walls allows rainwater into the building, which can cause extensive damage to masonry, plaster and timber. Regular inspections are advised in order to detect damp issues and when a building is compromised, there may not be any immediate signs.

Above Average Rainfall

Ask anyone in the London area about rain and they will agree that rainfall seems to be higher than usual. If you haven’t had your roof inspected recently, perhaps now is a good time to book an independent damp survey and find out if your home is impacted by penetrating damp. Blocked guttering, for example, can lead to rainwater running down exterior walls and if this is not addressed, the damp will penetrate to the interior walls.

Tell-Tale Signs of Penetrating Damp

The tell-tale signs include the following:

  • Patches of damp on internal walls that do not dry out
  • Plaster/paint deterioration
  • Salt stains on walls, tide marks
  • Rotting timber
  • Damage to skirting boards and window frames
  • Mould on internal decorations and fittings
  • Musky odour in the house
  • Moss growing on external walls

Watermarks on internal walls are a sure indication of penetrating damp and if you should notice any of the above signs, contact us on 020 8945 5547  and book an independent damp survey to get a definitive answer. We provide the homeowner with a detailed report within 24 hours of the survey completion. Should remedial work be required, we have a close working relationship with one of London’s leading damp-proofing companies.

Typical Causes of Penetrating Damp

Penetrating damp can be caused by the following:

  • Driving rain can penetrate brickwork, masonry and compromised render
  • Blocked guttering and downpipes
  • Leaking roof
  • Leaking window and door frames

Damp-proofing must be completed before repairing damage caused by penetrating damp, otherwise, the problem will persist.

How to Treat Penetrating Damp

Penetrating damp can be caused by compromised cavity wall construction and might require a DPC foam to be injected into the cavity and the application of waterproof render. A comprehensive roof inspection is advised if you notice signs of penetrating damp, which is one part of our independent damp survey package.

Penetrating Damp Treatments

The following are used to combat penetrating damp:

  • Removal of damaged plaster/timber
  • Use of salt neutraliser
  • Tanking slurry
  • Use of waterproof render
  • Application of new waterproof exterior render
  • Sealing external walls with clear silicone

The most important factor is to pinpoint the origin of the moisture penetration, then the remedial work can be done and after that, the damp damage can be repaired. If you repair damage caused by penetrating damp without first identifying the cause, you could be wasting your money, as the damage will return if the penetrating damp issue is not resolved.

How to Book an Independent Damp Survey

If you would like to book an independent damp survey from a leading London provider, we are the go-to company in all London Boroughs. Our PCA-certified surveyors use cutting-edge digital tools and equipment to accurately determine the presence of damp, mould and timber rot.

Call 020 8945 5547 or fill in the online form on this website and we will arrange for one of our certified damp surveyors to inspect your London home.

FAQs
What is the difference between rising and penetrating damp?

These two terms are often mixed up. Rising damp comes from the ground, if moisture enters a building from the roof or external walls, it is known as penetrating damp. Both are equally destructive and you can waste money if the damp is misdiagnosed.

What are the most common signs of penetrating damp?

The common signs of penetrating damp include damp patches and tide marks on walls and ceilings, moss growth on external walls signifies a source of moisture and this needs further investigation. If you notice a musky smell in the house, or bubbling paint and peeling wallpaper, this is a sure sign that damp is present. You can book an independent damp survey with London Damp Specialists and find out whether or not your home has damp, mould or timber rot issues.

What is the best way to inspect my roof?

Climbing onto a roof presents danger and we would never recommend that a homeowner do this. We provide an independent damp survey that includes a thorough roof inspection; our surveyors operate drones to get a close-up view of every square inch. They can see the guttering, examine the timber fascia and soffit boards and upper walls can be inspected, looking for signs of penetrating damp. You could book a roof inspection from a local roofing company but that would not include a damp survey on the whole house.

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For an in-depth survey of your property or simply to talk to one of our damp proofing specialists in London.

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