Once on site, our Engineer will initially undertake a walk through of the property to determine if all activities on the pre-test checklist have been completed – e.g. trickle vents closed and sealed; extract vents sealed and water traps sealed or filled. Unless already supplied, we will need to calculate the envelope area of the building (m²) and to log down the target Air Permeability Rate to be achieved.
A temporary air-tight screen is then fitted to an agreed entrance door to the building. A fan is then mounted into the screen and activated to blow air into or out of the building to create a price differential between inside and outside of approximately 50 Pa (Pascals). Up to 7 readings are taken with a no more than 10pa difference. A mean average is taken to establish the buildings leakage rate @ 50pa.
Additionally, both before and after the test, our engineer will take a number of other readings, including barometric pressure, internal/external temperature and wind speed . Through the use of specialist software and the fan in operation, our engineer will be able to fully carry out the test and measure the Air Permeability Rate for the building.
To set up and conduct a single Air Test will take approximately 1 hour, and whilst nobody can be allowed to enter or exit the building during the test itself, tradesmen or contractors can remain working inside throughout the testing process.