We have been working closely with Green Power House on a Zero Carbon project in Wiltshire.
Air Leakage Testing
We provide accredited air testing to complement our energy assessment – SAP, SBEM and Dynamic Thermal Modelling services.
Air-tightness of a building is also known as 'air permeability' and when measured is referred to as the buildings air leakage rate. Air leakage can occur through gaps, holes and cracks in the fabric of the building envelope (service penetrations, wall/roof junctions etc), which are not always visible.
Air leakage affects the building's performance and is one of the key areas in meeting or exceeding Building Regulations Part L standards for low carbon buildings, Code for Sustainable Homes and BREEAM. Making a building air tight reduces the amount of fuel needed to heat it, which in turn reduces the CO2 produced, reduces your carbon footprint and your energy bills.
The air tightness strategy should be developed in line with the fabric and ventilation proposals. We have vast experience in delivering air leakage rates of less than 3m3/(h.m2), which is often a requirement on many Code 4, 5 and 6 dwellings.
Part L of the Buildings Regulations requires that all non domestic buildings, which have a gross floor area greater than 500m2, be subject to mandatory air permeability tests.
For domestic dwellings, as a minimum, a representative sample of houses (in a development) must be tested.
An air test is not required for every dwelling on a site; a test is required on three units of each dwelling type or 50% of each dwelling type whichever is the least.
For dwellings that have undergone a pressure test their respective values are then incorporated within the SAP assessment. Dwellings that are not to be tested are liable to have a confidence applied to their correlating results from the plots actually tested. The applicable confidence factor is currently set at 2m3/(h.m2) at 50Pa. Developers should be aware of this when agreeing to design stage air leakage rate.
This means that in order to achieve building regulations compliance the maximum design stage air permeability rate should not be set higher than 8.0; thus allowing for the confidence factor to take the results of plots not tested to 10. For Code 3 or 4 schemes the air leakage rate will typically need to be significantly better than this (3 and below).
Air Leakage Testing when it suits you
We will fit in the test around you, give advice on how to prepare, provide advice on how to pass and provide feedback directly after the tests have been completed.
We have been in business for 20 years, specialising in low energy/emission buildings. Our experience extends to PassivHaus design, Thermal bridging and modelling, Code and BREEAM assessments, which complement our IATS air testing services. We understand the principles and our technical capability provides a complete service.
Remember: Build Tight, Vent Right.