Condensation risk


High levels of humidity in buildings can result in harmful condensation building up on internal surfaces and also within roofs, walls and floors. Condensation within building elements (usually referred to as interstitial condensation) can result in rot, rust and decay and lead to building failure; it can also reduce the performance of thermal insulation, increasing the rate of heat loss through the building.

Building Regulations and Standards recommends that condensation risk analysis is carried out to determine whether or not there condensation is likely to occur, and whether it will be harmful.

We can assess the risk of condensation occurring within a structure, working to the latest standards (BS 5250:2011 and BS EN ISO 13788:2012), taking account of:

  • the materials used in the construction;
  • the external environmental conditions;
  • the temperature and humidity levels within the building.

We provide a report which shows whether or not there is risk of condensation, and can advise on the results of the calculation. You can view a sample report here.

A single calculation costs £20.00, while combined U-value and condensation risk analysis for a construction costs £25.00. We offer discounts for bulk calculations and regular customers.