Building Regulations, Document L, FENSA, Double Glazing, Replacement Windows, UK, Pilkington K

Building Regulations for Windows and Doors

In England and Wales building regulations Part L, and its accompanying Approved Document cover issues relating to the conservation of fuel and power. 

Suppliers must prove that their windows meet the minimum energy efficiency requirements of U2.0 for wooden and PVC-U frames, and U2.2 for aluminium frames as of April 2002.

The accepted and most accurate way of calculating a U Value is through 'hot box' test. These however are both expensive and time consuming.

The UK's leading supplier of Glass to the replacement window market - PILKINGTON have however made things somewhat simpler by working with many of the UK's leading profile manufacturers and carrying out full hot box tests on a variety of their frames fitted with Pilkington Insulight™ Therm insulating units. 

The table below shows some of the window systems proved to conform to DOC L of Building Regulations - All these profiles have achieved Part L compliance when fitted with Pilkington Insulight™ Therm insulating units.

The tests were carried out at the National Physical Laboratory, Middlesex using insulating units containing Pilkington K Glass™.
Other units in the Pilkington Insulight™ Therm range use different types of Pilkington low E glass for even greater energy efficiency.
Thermal performance of any unit can also be improved by filling with argon rather than air.
*Achieves U value 1.74W/m2K.
**Achieves U value 1.75W/m2K. Air filled also achieves <2.0W/m2K.

For more information on U Values - visit http://www.windowstoday.co.uk/pilkington_k_glass_uk.htm