The energy efficiency of a building is an integral part of Building Regulations and PART L – the Conservation of Fuel and Power concerns itself with reducing the CO2 emissions. Windows and doors need to meet certain criteria in order to comply with this.
Changes in the regulations in October 2010 have meant that windows and doors need to be more energy efficient than ever before. There are two methods for proving compliance with building regulations – U Value performance or Window Energy Ratings (WERs).
Below shows the current minimum standards for compliance with Part L:
WINDOWS
U Value : 1.6 W/m2K
Window Energy Rating: C
Centre Pane U Value: 1.2 W/m2K*