Our qualified air testers carry out airtightness testing towards the end of construction to measure uncontrolled air leakage through the building envelope. The results support Part L compliance, SAP or SBEM calculations, EPC production and Building Control sign-off. If a building does not achieve its target air permeability, we can help identify likely leakage paths and provide practical guidance on areas to review before retesting.
By working with your architect or building designer from the early design stages, we can help develop practical timber frame solutions that place airtightness at the heart of the building fabric. With careful detailing, coordinated junctions and the right specification, our systems can achieve very low levels of air leakage, supporting improved energy efficiency, reduced heat loss and the performance standards required for low-energy, net zero or Passivhaus-led projects.
Highly airtight buildings need a carefully considered approach to fresh air and ventilation. Our energy assessors can advise on passive ventilation strategies to support Part O compliance and help manage overheating risk. Where mechanical ventilation is required, we can also work with your mechanical engineers to help ensure the chosen system is coordinated with the building fabric and operates as efficiently as possible.
Airtightness is key to achieving high energy performance in a timber frame building. By reducing uncontrolled air leakage, it helps retain heat, lowers energy demand, and reduces running costs. Improved airtightness also supports compliance with Part L, contributing to better EPC ratings and a lower overall carbon footprint.
Airtightness is measured through blower door testing once the building envelope is complete. Our in-house, qualified testers carry out these tests to verify performance against design targets and regulatory requirements. By combining robust detailing, thermal junction modelling, and site testing, we ensure consistent and reliable results.
No. Modern buildings are designed to be “airtight but well ventilated.” By limiting uncontrolled air leakage and incorporating properly designed ventilation systems, we ensure a constant supply of fresh air while effectively managing moisture. This approach improves indoor air quality, prevents condensation risks, and maintains a comfortable internal environment.
