Air Tightness Testing
What we do
Air Leakage Testing Ltd has a team of experienced test engineers registered with ATTMA to provide air testing for Part L1A (new dwellings) and Parts L2A and L2B (new buildings other than dwellings), as well as Passive House and other Low Energy schemes:
Our Air Test Engineers are home-based and well-placed to cover Greater London and the City, Kent, Essex, Surrey, Sussex, Hampshire, Berkshire, Buckinghamshire, Hertfordshire and Bedfordshire, we are able to test all over the UK.
We also offer advice and support on achieving air tightness through design reviews, site inspections and tool box talks/demonstrations on early completion tests. In addition, if buildings fail to achieve their targets, our engineers can demonstrate and explain the issues onsite using the test equipment and/or smoke, report the issues using photographs and snagging sheets then assist with identifying appropriate solutions.
In addition, we are able to undertake air pressure testing for other purposes including:
Air Tightness testing is a requirement for all new buildings. Testing must be conducted by a competent person, typically a company registered with the Air Tightness & Testing Association (ATTMA).
Air Tightness is a key factor in achieving an energy efficient building fabric in combination with insulation. The England & Wales Building Regulations require air tightness to be measured through site testing.
How it works
- We provide a quote based on the size of the building and location – it is usually helpful to have PDF Plans to calculate the size of larger buildings
- We provide a checklist and agree a date
- We call you ahead of the test date to talk you through the preparation and process and agree the timings. We would also look to confirm the air permeability that has been targeted in the energy model at this stage, if it hasn’t been discussed already. The results of the test are a key component of the calculation of the overall energy efficiency of the building and, therefore, achieving the necessary air tightness is a critical part of building control sign-off.
- On houses and flats we would typically complete the temporary sealing for the test when we arrive on site. For larger buildings, we would talk you through what would need to be done in advance of our arrival.
- We conduct the test. Testing is done through a pressure test whereby fans are installed into a doorway of the building and used to create a measurable difference between the pressure inside and outside of the building. The amount of air needed to maintain this difference can be used to indicate the volume of air escaping through the fabric (what would be draughts in the building’s day-to-day life).
- If the building doesn’t achieve its target at the first time of asking, we can use our equipment to identify the leakage paths. If these can be addressed relatively quickly, then we can repeat the test on the same day. In order to achieve increasingly challenging energy performance targets, air tightness requirements are becoming tighter. Typically, a good level of air tightness can still be achieved with excellent attention to detail in the decorative finish but, to achieve tighter targets, consideration must be given to air permeability within the design of the fabric, including use of membranes and tapes to maintain the air barrier – please see FAQs
- We issue ATTMA certificates for each test.
The below checklists can be downloaded and used to manage air testing from design/planning, through construction to preparation for the test:
Why use ALT?
- Helpful – we work with you to achieve the best result, identifying potential issues and repeating the testing once these have been addressed. We are on hand to answer any questions before, during and after the testing
- Knowledgeable – we have been air testing since 2002 and all our test engineers have a vast amount of experience
- Flexible – we try to fit in with the dates and times you need the test, we try to work around other trades to minimise disruption on site
- Responsive – we issue quotes and certificates within 1 working day, our lead-times are typically around a week but we will try and fit you in sooner if required
- Great value – our prices are very competitive but we can also undertake air and sound testing on the same visit to save you more money. If you do manage to find the testing cheaper, we will beat any quote.