Yesterday the Chartered Institution of Building Services Engineers (CIBSE) published a draft consultation of its airtightness testing methodology, which can be viewed here

This follows the government’s announcement in the Future Homes Standard Consultation that they were in the the process of approving a methodology that was independent of all organisations with an associated competent person scheme:

Chapter 5 of the consultation contains the proposed changes for airtightness within Part L of the Building Regulations. They include:

Extract from the Future Homes Standard Consultation (Part L and F) Revising the approved methodology 5.17. To ensure that the approved methodology for airtightness testing is independent of all organisations with an associated competent person scheme, we propose approving an airtightness testing methodology written by the Chartered Institute of Building Services Engineers (CIBSE), an independent organisation. A draft consultation version of this methodology will be available on the website by mid-October.


There is a major change proposed for the calibration of equipment, whereby CIBSE are advising testers to follow the manufacturers guidelines as opposed to carrying this out annually. This could potentially spell big savings for testers to the tune of hundreds of pounds per year.

iATS scheme coordinator Jennifer Hartley comments: “We very much welcome this consultation and look forward to responding. iATS is currently reviewing the information provided in the revised draft of CIBSE TM23. We strongly encourage our members to respond to this important consultation, and we will be keeping members informed of our thoughts over the coming weeks.

iATS will be submitting a response to the consultation, which will be available to view in due course, and we encourage you to also read the consultation and submit your feedback before the deadline of 10th January 2020. 

Categories: News item