Air-Tightness & Building Thermographic Surveys

Heat loss in a building occurs by two means, Fabric Heat Loss and Ventilation Heat Loss. Our heating equipment is designed to offset these losses and is sized accordingly.

Improvements in insulation can control the amount of heat loss through the fabric (e.g. floors, walls and roofs). Ventilation Heat Loss is caused from controlled air flow into and out of our buildings through purpose designed ventilators which provide a comfortable and safe environment for occupants.

Uncontrolled ventilation (infiltration) though gaps and cracks in the building fabric can lead to an increased heat loss of up to 30% additional to the designed load. A lack of insulation will reduce the performance of your building fabric. Air-Tightness and Thermographic Surveys can identify such problems and therefore highlight remedial actions to rectify the situation.

Building Air-Tightness Testing

The air-tightness of a building is based on Air Permeability. A ’Blower Door System’ is used to conduct an Air-Tightness Test.

The test is conducted by temporarily installing variable flow portable fans in a doorway, or other suitable external openings. All other doors and windows are closed. Mechanical extractor fans and fireplaces are temporarily sealed. The test fan is then switched on and the building is pressurized to 50 Pa.

The following table provides current normal and best practice air-tightness criteria for Dwellings;

Type	Air Permeability m³/ h.m² @ 50 Pa
Type	Normal	Best Practice
Naturally Ventilated	9	3
Mechanically Ventilated	5	3

Building Thermographic Surveys

Thermography, is the production of non-contact infrared pictures from which temperature measurements can be made.

A Portable infra-red camera is used to conduct a Building Thermographic Survey. The camera is used to scan building surfaces to detect temperature variations indicating defects often invisible to the naked eye. It is a non-invasive and cost effective diagnostic tool.

Air Tightness & Building Thermographic Surveys

Combining Building Air-Tightness Testing and Building Thermographic Surveys will both quantify and identify heat leakage from your building. Rectifying such defects will firstly increase the energy efficiency of your home and ultimately save you money.