What is condensation?

What is it?

Condensation is droplets of water that can be found on mirrors, windows and even walls. It makes your home damp and can cause mould on walls, furnishings and clothes.

It can occur in any building, and is the most common cause of dampness.

What causes it?

If there is too much moisture in the air and not enough fresh air moving through your home.

These things can make it worse -

  • Keeping windows and doors closed
  • Not using extractor fans if provided
  • Steam or moisture in the air from cooking or baths and showers
  • Drying clothes on radiators or in a closed room
  • Keeping too many items in a room that stops the air from flowing
  • Lack of loft insulation or items covering loft vents

How do I know I have it?

It is usually condensation if -

  • It’s found on north-facing walls, but it can occur on any wall if it is cold
  • It’s found in corners, in cupboards and under work surfaces (where there is little air movement)
  • You have checked pipes and overflows and under sinks and there are no leaks
  • There are no slates missing from the roof, no cracked gutters and no cracked rainwater pipes
  • Your home is over 18 months old (new homes take about 9 – 18 months to dry out after building work)

How can I prevent condensation?

• Try to keep your house warm most of the time

It makes sense to keep your heating on at a low temperature all day rather than trying to heat it up all of sudden and very quickly in the evening.  This is because most houses take a long time to warm up and a cold house means more chance of condensation.

• Keep air flowing

Try opening the window a little for a while to allow the air to flow. Keep your trickle vents (the small vents at the top of the window) open. You could open a window and keep doors open to rooms.


If you notice any of these things in your home, then you may have damp or a leak.

  • Damp musty smells
  • Paint cracking or deteriorating
  • Damp marks around chimney breast
  • Damp stains, damp mould or white chalky marks on walls
  • Staining of wall coverings
  • Evidence of dry rot fungal growth on walls and structural timber
  • A discoloured or white tidemark on walls, indicating rising damp

Signs of a damp problem outside of your property:

  • Water marks on walls
  • White chalky marks on walls

Moss or vegetation growing on the exterior of buildings

If you are worried about any of the above, please ring our offices for advice.