Why Air Tightness Testing Matters
Air tightness testing — also known as an air pressure test or air leakage test — is a mandatory requirement for most new build homes and commercial buildings under Part L of the Building Regulations. It measures how much uncontrolled air passes through the fabric of a building, giving a result that confirms whether the structure meets the required energy efficiency standard.
At APT UK, we’ve been carrying out air tightness tests across Northamptonshire and the wider UK for many years. We know what a good result looks like, we know how to identify issues quickly if they arise, and we know how to work with you and your team to resolve them efficiently.
An airtight building is a more energy-efficient building. When air leaks freely through gaps, cracks, or poorly sealed junctions, it drives up energy use, increases running costs for occupants, and makes it harder to control indoor temperature and comfort. For new builds, demonstrating a compliant air leakage rate is a legal requirement before completion — so getting it right first time matters.
If a building doesn’t pass its air test, it can delay handover, create programme problems, and add unexpected cost. Our job is to help you avoid all of that.
Our Process is Straightforward
How it Works
We’ll agree a suitable time, attend site with our calibrated testing equipment, and carry out a full air pressure test in line with current methodology. The test pressurises or depressurises the building and measures the rate at which air passes through the building fabric. The result — expressed as an air permeability figure — is then compared against the design target.
We’ll explain your results clearly, on site, as soon as the test is complete. If the result is compliant, we’ll issue your certificate promptly. If improvements are needed, we’ll walk you through exactly what to look for and how to address it — so there’s no guesswork and no unnecessary delay.
Our Process is Straightforward
How it Works
We’ll agree a suitable time, attend site with our calibrated testing equipment, and carry out a full air pressure test in line with current methodology. The test pressurises or depressurises the building and measures the rate at which air passes through the building fabric. The result — expressed as an air permeability figure — is then compared against the design target.
We’ll explain your results clearly, on site, as soon as the test is complete. If the result is compliant, we’ll issue your certificate promptly. If improvements are needed, we’ll walk you through exactly what to look for and how to address it — so there’s no guesswork and no unnecessary delay.
Our Air Tightness Testing Services
We’re regulated by the Elmhurst Airtightness Scheme (EAS) and work closely with local authority building control, approved inspectors, and warranty providers.
Based in Weedon Bec, Northamptonshire, we cover the local area daily — including Northampton, Corby, Kettering, Wellingborough, Daventry, Towcester, Thrapston, Market Harborough, and Brackley. We also provide a full national service across the UK.
Get in Touch
Ready to book, or just want to talk through what’s required? Call us today and we’ll be happy to help. Ask about our free pre-test checklist — a practical guide to help you get your site ready before we arrive.
