The BSR and Condensation Assessments

A BSR (Building Safety Regulator) submission against Building Regulation Schedule 1 Paragraph C2(c) needs to demonstrate that condensation and mould growth risk has been minimised.  Typically, the guidance in Approved Document Part C would be sufficient however some of the standards listed have been replaced or superseded. This is important as a BSR submission should be compliant with the most up to date standards.

The matrix below describes our view on all the standards against which compliance for fabric elements must be demonstrated, including the standards which have replaced the outdated documents referenced in the Approved Document Part C. The table covers:

• Interstitial condensation which determines the risk of moisture accumulation within a construction build-up.
• Surface condensation which determines the risk of moisture developing on the surface of construction elements and junction interfaces.

Carrying out the assessments, as noted in the table below, for every building element would take a very long time. It is therefore critical that professional judgement is used to determine the appropriate number of assessments. We would expect all designers to follow the design principles laid out in standards such as BS 5250:2021 but for any elements where these design principles do not apply using prescribed calculation methodologies could help the design team to reduce risk.