Thermal Performance & Air Leakage

​The Government is committed to the reduction of greenhouse gases as a result of the Kyoto agreement on Climate Change. The Building Regulations for England, Wales and Scotland, which cover Conservation of fuel and power, have been updated accordingly. The revised Regulations require buildings to:

  • Have more insulation in the building envelope.
  • To limit heat loss from pipes and ducts.
  • To provide more energy efficient lighting, heating, cooling and ventilation systems.

In the drive for energy efficiency the revised Regulations set minimum acceptable levels for natural daylighting and refer to CIBSE LG10 for additional guidance. That publication explains the value of natural daylight on human performance and thus on energy efficiency in its widest sense. Widespread research links natural daylighting to tangible work place benefits: improved retail sales, lower staff absenteeism, faster hospital recovery rates, and improved school exam results.

Natural lighting should be provided in all buildings. Windows can provide daylight to areas within 6 metres of a window, but rooflights are the only practical means of introducing daylight to any wider buildings.