Condensation Control

What is condensation?

Condensation is the process where the water vapour in the air turns into a liquid as a result of warm air hitting of a cooler surface. You will have noticed condensation occurring on a cold glass of water on a hot summers day.

Condensation usually evaporates back into the air, however, it can be extremely problematic within buildings. 

Signs of condensation

The most common sign of condensation is the water running down walls, a musty smell, or when mould, mildew or fungi are visible on windows, corners of bedrooms and behind furniture.

The damp in properties that have been constructed in the last 40 years is 90% more likely to have developed as a result of condensation due to the warm moist air formed from cooking, washing, bathing as well as breathing on cooler days.

Signs of Condensation

Health Implications

Condensation can have serious health implications as mould, mildew and fungi can cause respiratory problems, such as asthma, and skin allergies. Those who are vulnerable such as babies, the elderly and those who have previous respiratory problems are most at risk.


Improving heating, insulation and installing a dehumidifier will aid in improving your condensation problem. Please bear in mind that these improvements are not a permanent solution as it does not treat the source of the problem.

We recommend you follow the following steps to aid in combatting your condensation problem:

  • Avoid drying clothes over radiators or in un-ventilated rooms. Drying clothes outside is better.
  • Open all window trickle ventilators if installed
  • Avoid the use of portable LPG gas heaters
  • Vent outside tumble dryers
  • Close bathroom and kitchen doors when bathing and cooking
  • Leave a space between walls and furniture
  • Remove any black mould that has grown on the paint, wood or timber
  • Using a ventilation system to remove the moist stale air.
  • Using a single or multi-room condensation control extraction fan (C-DMEV - D-MEV) to continuously extract the moist, stale air is continually.

Positive Ventilation Unit (PIV)

Our range of top-quality PIV's are energy efficient units that control condensation by gently providing air to your home from a central position in the stairwell or store room. A loft mounted PIV draws fresh air and heat that exists in lofts, filters it and pushes it into the dwelling via a ceiling mounted diffuser simultaneously circulating existing heated air that has risen to ceiling height. All stale air in the property is forced out through natural forms of ventilation such as doors and windows or a condensation control fan.