An at least two person team proceeds with the transport and deployment of the Blower Door ® system at the testing site.

Every opening that is not an opening or a glaring fault, such as cracks and cavities, must be completely sealed, usind the impermeable plastic of the Blower Door ® system, fixed with carpenters tape or aluminium tape in case the surface is excessively slippery.

The entry door will be sealed using the aluminium framework and impermeable fabric, where the fan will be embedded. To this cloth a tube from the outside will have to be connected, in order to measure the baseline pressure.

The fan will be connected to a laptop computer with the pertinent control software installed.
After measuring the baseline pressure, the program will operate the fan until the required overpressure or underpressure is achieved, depending if the test is one of pressurization or depressurization; both are needed to obtain the necessary indexes.

The control system will evaluate the air flux for diverse pressures, generally in intervals of ten between seventy and thirty Pascals.

While the test is underway, a data gathering is carried out using a thermographic camera, in order to identify concrete faults and phenomenons in the building.