What Causes Damp and Moisture Around the Home?

 The first course of action when curing a damp problem is to establish where the water source is and how it is gaining entry in to the walls. Check the following areas:

Broken or perished damp-proof course (DPC)

If the dampness is on the ground floor, beginning at ground level or below, a faulty DPC may be implicated. This may not be easy to establish by eye or without invasive investigations, so should be considered once all other sources have been eliminated. If the property has suffered from subsidence, the DPC may well have been ruptured.

Bridged damp-proof course

It is not uncommon for the ground levels surrounding a property to slowly rise as garden debris and external finishes such as decking and driveways are added. Check the perimeter of your property and be sure that these surfaces do not carry water to a level higher than your DPC, effectively rendering it useless. Cavity wall insulation is also capable of bridging the DPC, so check that this has been properly installed and does not pass below the level of the DPC.

Broken or blocked guttering

Broken or blocked rainwater goods such as guttering, drainpipes, roofing and flashing can be large contributors to damp. If rainwater isn’t conducted safely away to drainage points, it will leak uncontrollably onto walls unprotected by a waterproof layer.

Defective ground and surface drainage

As they meet the external perimeter, surfaces butting up to the walls of your property should be angled slightly upwards so that rainwater drains away from the building. If ground drainage is blocked, rain and waste water will not be able to drain away promptly, and the property is at risk of flooding.


This is caused by humid air hitting a cool surface, so check that kitchens, bathrooms and boilers are well ventilated to carry this moisture rich air away. The area beneath suspended wooden floors is highly susceptible to condensation, so check that there are sufficient airbricks (all sides of the property, every 180cm (5ft 11in)) and most importantly that they are not blocked by garden debris or cavity wall insulation.

Sub-floor and chimney ventilation

Leaking plumbing

Leaks are most often at the joints between shower trays or bathtubs and the walls, so check that sealant and grouting is in tact and continuous. Also check pipework for leaks, particularly at joins, which may simply be rectified by a new joint or washer.

Masonry & chimneys

Check brickwork, rendering, stone and plinths for damage that compromises the waterproof surface.

If the damp is in walls above a fireplace (not necessarily in the same room as the fire, but the room above!), hygroscopic salts are likely to be drawing moisture into the masonry.

We detect damp areas using thermal imaging – non-invasive approach.

Contact Us today for a quote.

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