About iATS

iATS is an authorised Competent Persons Scheme created for companies (including sole traders and partnerships) that carry out Air Tightness Testing. The Scheme is owned by Elmhurst Energy, the largest accreditation body for energy efficiency professionals in the UK, who support and promote the scheme to its wide membership base.

Air Tightness Testing, also known as Air Permeability Testing, Air Leakage or Air Pressure Testing plays an important part in establishing the energy performance of a building. Air testers use blower door testing equipment to establish the air leakage occurring through gaps and cracks in the building fabric. Too many of these leaks can effectively result in unwanted heat loss, which is reflected in the results of the air pressure test.

iATS, as a recognised competent persons scheme are dedicated to ensuring that Air Testers provide quality and accurate air tightness testing reports for developers and building control bodies. Our leading air tightness testing scheme provides reassurance to clients that the work is carried out to a high degree of quality and integrity. You can search for one of our qualified Air Testers below:

Level 1 Testers – Authorised to test dwellings and non-dwellings up to 4000m3 for building regulation compliance purposes

Level 2 Testers – Authorised to test at Level 1, and large buildings over 4000m3 for building regulation compliance purposes

Background Ventilation Testers – Registered to test for the assessment of background ventilation of existing buildings  

Our Principles

We operate our scheme based on the Aims and principles shown below


We provide reassurance to clients that the work carried out by iATS members are to a high standard of quality and integrity.


We are dedicated to providing the highest level of technical support to our members, and always respond to tester concerns.

Trusted, Impartial and Transparent

As an independent scheme we endeavour to be trusted, transparent and professional in the eyes of all stakeholders.

Latest News

Take a look at the latest news from iATS

Updated CIBSE TM23 released

The Chartered Institution of Building Services Engineers (CIBSE) has published the final version of its airtightness testing methodology, TM23 Testing buildings for air leakage (2022) . This new methodology is due to come into force in Read more…

Get in Touch

Find us at the office

The Independent AirTightness Testing Scheme Ltd

16 St Johns Business Park,
LE17 4HB

T: 0300 688 0016
E: manager@iats-uk.org

Opening Hours
9am - 5pm (Mon- Fri)

The Independent AirTightness Testing Scheme Ltd is registered in England, Company Number: 09309058

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