Air Pressure Testing

Air pressure testing assesses air permeability or air infiltration of the building structure which can lead to undesirable draughts, heat loss, increased fuel and carbon usage. By testing the air pressure of the new build domestic property it is possible to calculate how well it will retain heat and potential asscociated CO2 consumption.

The Building Regulations 2006 Part L1a Conservation of Fuel and Power in New Dwellings – details a legal requirement that new build domestic properties must conform and pass a mandatory air pressure tightness test before becoming occupied.

All buildings require a certain amount of air to be allowed to flow around the building and be exchanged to facilitate the removal of pollutants, combustion air and to adapt to the moisture content which allows a healthy living environment. There are 2 seperate types:

  • Controlled ventilation, for example a trickle vent situated on a window.
  • Un-controlled ventilation i.e. gaps around pipe entry points or around windows.

Controlled ventilation – calculates how much air flow is required to permeate the building to provide adequate ventilation.

Un-controlled ventilation – is the free flow of air in and out of the new build structure. This can cause unwanted draught and wastes energy used to generate heat for the property, causing inefficient heating systems and increased carbon emmisions.

An airtightness test calculates these losses and allows for the property to be tested and assessed against the targets set out by the building regulations and the properties’ design requirements. Air pressure testing can also help assess the quality of the new build construction to some degree.

How is air pressure testing carried out?

Air leakage testing involves using a powerful mobile fan and sensitive computer monitoring equipment which has specifically calibrated. The fan is located at an external door where the property can be pressurised or depressurised and air leakage can be assessed as this process is carried out.

Air pressure testing can be undertaken by a competent person. The British Institute of Non-Destructive Testing (BiNDT) runs a registration scheme of competent persons to ensure adherence to procedures, quality of service and UKAS calibration of equipment.