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The causes of penetrating damp

Damp is a problem that many homeowners face and while it may be tempting to ignore the issue, unfortunately it will only lead to more serious problems in the future.

There are three causes of dampness – penetrating damp, rising damp and condensation. Below we provide information on everything you need to know about penetrating damp from what causes it, to how to treat it.

What causes penetrating damp?

Penetrating damp is also sometimes known as rain penetration. It can occur through walls, roofs, window or door surrounds, and traditionally happens when water finds its way from the outside of your property into the inside.

This type of damp can be found at any level of a building but it’s usually more prevalent higher up and on walls which face south west.

There are a number of sources which can cause penetrating damp including:

  • Different types of building defects can cause problems including overflowing gutters, missing roof tiles, downpipes, leaking pipes, badly fitted doors and/or windows, damaged pointing, cladding, flashing and render or dilapidated or poorly installed windows.
  • Porous walls – ageing bricks lose their ability to keep out rain penetration.
  • Spalled bricks and degraded mortar – damage to brickwork can allow water to penetrate into your home.
  •  Air bricks which are covered can also cause problems because it prevents the building from ‘breathing’ by restricting the flow of air and trapping moisture. This in turn will cause damp.

What are the signs of penetrating damp?

If you notice one or more of the following, it could be a sign of dampness in your home:

  • Penetrating damp usually shows up through damp patches on walls or ceilings, which may darken when it rains.
  • Growing circles of damp on walls or ceilings.
  • Blotchy patches on walls.
  • Wet and crumbly plaster.
  • Signs of spores or mildew.
  • Drips and puddles.

How to prevent penetrating damp

The good news is that there are a number of things you can do to prevent the onset of dampness including:

  • Be vigilant – check seals, connections and waste pipes on domestic appliances regularly.
  • Check your loft for signs of water coming through the roof.
  • Check exterior walls for decay, crumbling or cracks.
  • Keep areas around damp proof courses and air bricks clear.
  • Don’t place planters directly against external walls.
  • If you’re replacing your driveway or any paving, don’t raise the levels because you may bridge the damp proof course.
  • Twice a year, check moisture levels with an electronic moisture meter.

What to do if you have penetrating damp

If you spot the signs of penetrating damp, it’s important to get the problem looked at as soon as you can because it will only worsen over time.

Peter Cox can provide you with a professional damp survey and provide effective, specialist damp proofing treatment. We carry out a detailed assessment of the extent of any damage and make recommendations on the type of treatment needed.

For more information about penetrating damp and the treatments that we offer, please feel free to contact Peter Cox to book a survey appointment or call us on 0808 273 2138 for further details.