Frequently Asked Questions

What is Air Tightness Testing?

Air tightness testing is the procedure to find any drafts and unwanted airflow through the building.

Air Tightness testing northern Ireland is essential to prevent air leakage which results in heat loss and higher C02 emissions.

Contact CPL Energy Services today to get your dwelling building control compliant which will result in a more energy efficient home and in turn more affordable heating costs.

If you are working on a Self-Build project or a Multiple Dwelling Site and you want to know more about EPCs then contact CPL Services of Omagh

How is an air tightness test carried out?

A blower fan is fitted to an external doorway, all internal doors opened and windows closed and the building pressurised (or depressurised), usually to 50 Pascals.

It’s a light pressure difference only, but enough to allow the accurate measurement of air leakage.

Design ventilation is closed and sometimes sealed, but no other temporary sealing work should be undertaken – the purpose of the test is to assess these unintended areas of air leakage!

When and why is the air tightness test required?

The test should be carried out only once the building is completed. It is required as part of final sign off for building control compliance, and to provide an as-built input to final SAPs and SBEM Calculations.

How is the air permeability calculated?

The Air Permeability figure is the level of leakage from the building in m3 per hour, divided by the envelope size in m2. So an envelope of 250 m², with a leakage air flow of 2,500 m3/h would give an air permeability of 10.0 m³/h/ m². It differs from Air Changes per Hour (ACH), in that the ACH is based on internal volume (m³) rather than envelope (m²).

Why have Energy Performance Certificates been introduced?

The EPC has its roots in the Kyoto Protocol which was a worldwide initiative started in 1997 to address the issue of Greenhouse gases. Since then the European Union have formulated the European Directive for the Energy Performance of Buildings, which applies to all member states with a clearly defined timetable of the measures we must introduce. Currently virtually every property in the UK including our homes, shops, offices, factories, schools and hospitals will require an energy rating.

An Energy Performance Certificate (EPC) is a certificate which demonstrates the energy rating of a building. It forms part of the ‘Energy Performance of Buildings Directive’ (EPBD) which the Government is currently implementing in nationwide.

The energy performance of a building is identified using an ‘A’ to ‘G’ grading system, similar to the energy grades provided with appliances such as a washing machine. ‘A’ is very efficient and ‘G’ is the least efficient.