Conservation of Fuel and Power

Energy and the Conservation of Fuel and Power

Part L, Technical Handbook 6 and Part F

For the latest information on Part L 2021, visit our Part L 2021 Hub.

In both England and Wales, Building Regulations for the conservation of fuel and power are covered by Part L and its accompanying Approved Documents. For Scotland, the regulations are supported by Technical Handbooks, Section 6 of which deals with energy. For Northern Ireland the regulations are in Parts F1 and F2, last updated in June 2022. There is also a corresponding Part L for the Republic of Ireland.

Ahead of the introduction of the original 2016 zero carbon homes target, the UK Government dropped its zero carbon buildings policy in England. However, new low energy homes are expected to become the norm following a consultation on Approved Document L in England. Published in December 2021 and in force since June 2022, the new Part L in England is anticipated to be followed by the Future Homes Standard in 2025.

One of the most significant changes in building regulations in the past few years was the introduction of  Window Energy Ratings (WERs) as an alternative to U values as a criterion for compliance.  WERs are a much more accurate indicator of the energy performance of a window because they take a range of factors into account, including the useful solar heat gain. For existing homes in Scotland, WERs are now an established route to compliance for replacement windows and windows for extensions.  

Window Energy Ratings are administered by the British Fenestration Rating Council (BFRC), Thermal Rating Register (Certass) and the BSI.  Detailed information on obtaining BFRC Ratings for windows can be found on:

Solutions to meet the requirements of building regulations include Pilkington Optitherm™ S1 Plus and the Pilkington K Glass™ Range of low emissivity glass that can be combined with Pilkington Activ™ self-cleaning glass and Pilkington Optiphon™ to give a broad choice of thermal and other properties. Particularly for non-dwellings, Pilkington Suncool™ is a range of solar control glass products that combine low emissivity glass, low U values with solar control with neutral appearance. 

Pilkington energiKare™ Advantage which can provide triple glazing performance in a double glazing. 

To view details of the full Pilkington range of Thermal Insulation glass to help you meet the new Part L regulations please click here.

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