Air tightness testing is a crucial part of delivering energy-efficient, regulation-compliant new buildings. If you’re a developer, builder or self-builder, you’ll likely need to carry out this test to meet the requirements of Part L of the UK Building Regulations.

In this guide, you’ll learn what an air tightness test is, why it matters, what it involves, and how it affects compliance and energy performance.

On 15th December 2021, the government published their updated Building Regulations for England, which included amendments to Approved Document F (Ventilation) and Approved Document L (Conservation of fuel and power), as well as the release of a new approved document for Overheating (Part O).

Here, we’ll take a look at how the changes to Part L, in particular, affect one of our services – Air Tightness Testing.

Air tightness is an important element of building regulations in the UK. Testing air tightness in new properties, as per Part L of UK Building Regulations can make a big difference to the energy efficiency of properties as well as how comfortable and well-heated they are for occupants. Better standards of air tightness will mean that there is less air leakage occurring, which in turn will make for a more robust building envelope and better heat retention and energy efficiency.