Condensation | damptec
Black mould at base of wall


Our surveyors will come to your property to diagnose if there are excessive levels of condensation by recording amongst other things the level of relative humidity against the ambient air temperature in your home.  We can then offer you detailed advice about how to reduce the levels of moisture.


Please note that we do not provide or install extractor fans or PIV units. We can however make recommendations with regards to the treatment of condensation and recommend the most effective extractor fans.


What is condensation?

There is always some moisture in the air, even if you cannot see it. If the air gets colder it cannot hold all the moisture and tiny drops of water appear. This is condensation. Kitchens and bathrooms are often primary sources of atmospheric water. Moisture is released into the air through normal daily activities such as washing, cooking, drying clothes, showering and bathing. This can occur commonly on windows or external walls, or cold surfaces within the fabric of the property. Look for it in corners, on or near windows, in or behind wardrobes and cupboards. It often forms on north-facing walls.


The problems of condensation can lead to staining and mould growth, damaging wall paper and wall surfaces, window frames, furniture and clothing. Black spot mould (Aspergillus Niger or Cladosporium spp), for example form pyramid profiles in wall corners and at wall/floor or wall/ceiling margins as a consequence of condensation.


Tiny spores produced by the mould and the higher numbers of dust mites due to the moist conditions can increase the risk of asthma and respiratory illnesses in some people.

Maintaining a reasonable balance between heating, ventilation and insulation can reduce excessive condensation. In the short term you should wipe off the condensed water from windows and sills every morning during the condensation season.

Black spot mould in classic pyramid profile in external corner
Condensation on a Window

How to avoid condensation

  • Reduce the potential for condensation by producing less water.

  • Some ventilation is needed to get rid of moisture being produced at the time, including that from people’s breath.

  • Keep trickle vents open at all times, alternatively open small windows/top lights.

  • Kitchens and bathrooms require more ventilation due to cooking, washing, bathing which means opening more windows.

  • Close the bathroom and kitchen doors when these rooms are in use, even if they have extractor fans. This stops moisture reaching other rooms, which are often colder and more vulnerable to condensation. 

  • Allow space for the air to circulate in and around your furniture.

  • Open doors to ventilate cupboards and wardrobes. 

  • Use a good quality extractor fan, in the bathroom and kitchen and any other rooms with running water, which are classed as wet rooms, and which therefore require ventilation.



                       PCA Condensation Leaflet


What is positive input ventilation? 

Positive Input Ventilation systems provide a continuous supply of fresh, filtered air into the home through positive pressurisation, creating an environment in which condensation and mould growth can’t exist. PIV is the UK’s most popular method of low-energy whole home ventilation.















Benefits to you:

  • Cures condensation dampness

  • Removes allergens and pollutants such as carbon monoxide

  • Extremely low power consumption and low running costs

  • Fit and forget - easy installation and very low maintenance required

  • 5 year warranty


For any ventilation products we would recommend that you contact Nuaire direct on 029 2085 8500 or visit the website at


Condensation on a Window

Damptec Systems Limited
Unit 45, The Clocktower Business Centre                   Company Number: 
Works Road, Hollingwood                                           VAT Registration Number: GB 
139 5306 07 
Chesterfield, S43 2PE