Air pressure testing is used to measure the air tightness of a building fabric, it is a requirement for all new build domestic and commercial projects assessed under Part L. The results are entered in the thermal models to improve the accuracy of the predictions, the lower the airtightness the more efficient the building fabric.

For residential properties, Part L1 has a minimum requirement of 8m³/h m² @50pa, in comparison Passivhaus has a lower air permeability target of <0.6ACH @50pa. For existing properties and retrofit, building regulations has no minimum standard whilst the Passivhaus EnerPHit standard has a maximum allowance of 1.0ACH @50pa. When working on existing buildings, it is good practice to perform pre and post air permeability testing to understand how the building performs and ensure performance will be as designed.

We provide air pressure testing to meet all Part L, Passivhaus and retrofit requirements.