WHAT IS PENETRATING DAMP?

Penetrating damp, otherwise known as lateral damp, is the end result of water successfully penetrating from the outside of a building and into your property.

Unlike rising damp, penetrating damp can happen at any level within the property including lofts, ceilings and walls.

It is a very common problem in older properties that have solid walls. Newer properties tend to have much more protection from penetrating damp through the use of cavity walls and are therefore less likely to suffer from this type of damp problem.


WHAT CAUSES PENETRATING DAMP?

Properties in an unsheltered position with no protection by surrounding buildings or trees are particularly susceptible to penetrating damp. This is due to prolonged exposure to wind driven rain. Any building situated in areas prone to high-intensity winds can suffer. This is particularly prevalent on the west coast.

When wind driven rain is not the cause, penetrating damp is usually caused by leaky pipes, poorly maintained brickwork or deterioration of mortar joints. 


CAN CAVITY WALL INSULATION CAUSE PENETRATING DAMP?

Cavity walls are actually quite effective at preventing penetrating damp and cavity wall insulation is an effective method for improving thermal efficiency in properties.

However, cavity wall insulation has been known to absorb moisture/damp and ultimately bridge the gap between the outside wall and internal plasterboard. Also, if it is installed poorly, gaps can lead to cold spots, condensation and mould occurring in the cavity wall. 


WHAT ARE THE SIGNS OF PENETRATING DAMP?

Here are some tell-tale signs that point to a penetrating damp problem:

  • Damaged plaster
  • Musty damp smell
  • Black mould growth
  • Damaged timber
  • Damp patches on walls that do not dry out
  • Damp patches getting bigger when it rains
  • Leaky roof

If you notice these issues, make a note of where the damp issue is within the property and go outside the property to see if you can see any problems in the external fabric of the building in the corresponding area that might be causing the issue. This could be something like a broken downpipe or missing roof slates. Also, remember to look inside for possible defective plumbing issues or burst water pipes.


WHAT DAMAGE CAN PENETRATING DAMP CAUSE?

The damage caused by penetrating damp can vary depending on how much water has managed to penetrate through to your property.

Penetrating damp can lead to black mould growth which carries a host of problems ranging from affecting your personal possessions, home décor and potentially your health. In cases where penetrating damp affects the timber in a property wet rot, or more severe dry rot, can occur as a result.

The key to most penetrating damp problems is firstly locating the point of entry for the moisture and resolving this problem. After cutting off the moisture you can then start to assess the damage caused by the penetrating damp and decide on what treatment is required.


ARE THERE HEALTH RISKS LINKED TO PENETRATING DAMP?

Musty odours, stained plaster and peeling wallpaper are unpleasant, but they typically do not pose significant risks to healthy individuals.

However, any dampness and mould can aggravate existing respiratory health problems, especially amongst elderly people, children or people with asthma. 

So, while dangerous is a bit of a strong word when talking about penetrating damp, residing in damp environments for extended periods is definitely undesirable. This means timely resolution of the problem is necessary.


PREVENTING PENETRATING DAMP: ADVICE

Dealing with penetrating damp promptly is essential, any part of your property exposed to damp for a long time will begin to deteriorate. To tackle this issue effectively, it’s crucial to identify its source. Penetrating damp primarily arises from external building damage. Here are common defects and potential solutions:

DAMAGED ROOF

  • Damaged surface on flat roofs
  • Missing, broken, or loose tiles
  • Faulty flashing around chimneys

Fix these by replacing cracked or missing tiles and flashing if you have the necessary expertise.

DAMAGED GUTTERS AND PIPES

  • Blocked and overflowing gutters
  • Cracked or broken downpipes
  • Continuous overflow from cisterns or water tanks

Fix these by unblocking or repairing damaged gutters and repair pipes to prevent dampness.

DAMAGED WALLS

  • Deteriorating mortar in brickwork joints
  • Blocked air-bricks
  • Defective detailing around windows and doors

Patch cracks using sealant or renew the render. Replace porous brick and coat with a damp proofing solution to protect brickwork.

While some property owners may be confident enough in their abilities to attempt the maintenance above, we would always recommend involving a qualified damp surveyor if you are unsure. Misdiagnosis of a damp problem and applying the wrong fix can exacerbate the issue and lead to costly repairs. A certified and qualified surveyor can provide accurate diagnosis and tailored solutions for your property and its specific needs.


HOW IS PENETRATING DAMP TREATED?

The key to most penetrating damp problems is firstly locating the point of entry for the moisture and resolving this problem. After cutting off the moisture you can then start to assess the damage caused by the penetrating damp and decide on what remedial treatment is required.

PENETRATING DAMP TREATMENT

When it comes to treating penetrating damp, the first important step is to establish and rectify the source of moisture/water ingress. Click the button below to learn how Wise Property Care approach penetrating damp treatment.


HOW MUCH DOES PENETRATING DAMP COST?

The cost of treating penetrating damp varies depending on the severity of the problem and the source of moisture ingress. If porous building materials is the only issue, a chemical barrier may suffice. However, other factors affecting cost may include fixes like replacing brickwork, re-pointing, and repairing gutters and downpipes.

As each case differs, tailored solutions are necessary and a visit from a surveyor to establish what is needed is always recommended. Unfortunately, there is no genuine one-size-fits-all “ball park figure” for this kind of treatment.


CONTACT A PENETRATING DAMP SPECIALIST

If you think your property needs penetrating damp treatment, and would like to arrange a penetrating damp survey with one of our fully qualified, experienced surveyors, then call Wise Property Care today or use our contact form below. 

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