What is interstitial condensation?
When internal warm air travels towards the colder parts of external walls or roofs and the temperature drops sufficiently, condensation occurs on surfaces within the insulation layer.
Any formed interstitial condensation evaporates during the summer months.
Air leakage within IWI systems carries a high amount of moisture and considerably increases the risk of interstitial condensation.
Addressing interstitial condensation
The SWIP IWI system is designed to be fitted with full intimate contact to the building substrate leaving no air gaps to negate the risk of both surface & interstitial condensation.
The SWIP IWI System has a choice of two solutions: a Vapour Open or Closed membrane. This depends on the location of the dwelling in the UK and its exposure to high levels of wind-driven rain.
VCL System Selector
You can find a VCL system selector on our website, where you can input the property address and receive a full project specification document via email.
The membrane’s variable vapour permeability adapts to changing conditions, preventing moisture build-up and safeguarding the building structure from mould and damage.
This open VCL is approved and tested by leading certification bodies, including:
- The British Board of Agreement (BBA)
- Passive House Institute
- The National Standards Authority of Ireland (NSAI)
Contact the SWIP team if you’d like to find out more about our insulation systems.
Phone: 0121 384 1029
Email: enquiries@swipiwi.co.uk
