The Government finally publish important energy saving changes to Part L of the UK Building Regulations

This week finally saw the publication by the UK Government of the new Building Regulations for existing and new dwellings. I downloaded the online version of L1B “Conservation of fuel and power in existing dwellings” as these major changes come into effect now for all property owners in England and Wales who will be installing windows and doors from 1st October 2010. The main purpose of these far more onerous requirements is to legally obligate UK home owners to fit high performance energy efficient energy saving windows and doors if on or after 1st October 2010 they a) replace existing any windows/doors, b) have an extension or c) build a new premises. There is currently no obligation to replace existing windows, even if old highly inefficient single glazed rotten windows, although who is to say that the incoming Government will not introduce a requirement for property owners to install energy rated double glazed windows in order to help reduce the UK’s carbon emissions, cutting energy consumption and heating bills.

Having had a brief look at the approved documents L1B on conservation of fuel and power, the big change as far as replacement windows and doors is concerned is that any windows installed on or after 1st October 2010 must now have a Window Energy Rating (WER) of at least band C (currently E) or a combined U Value of 1.6 W/m2K, and doors a combined U Value of a maximum of 1.8 W/m2K. There appears to be a (yet to be fully explained) exception where replacement windows can not meet above for appearance or building character reasons, where a centre page U Value of 1.2 W/m2K may be accepted. The exemption applies only where the energy efficiency requirements would “unacceptably alter the character or appearance” of existing dwellings. However, I suspect this will literally be the exception, rather than the rule!

Another requirement of L1B for existing dwellings is that insulated cavity closers should be fitted by installers where appropriate. Other things that are of note include the fact that whilst the Window Energy Rating method of compliance is now established as shown in both the HM Government L1B and L2B approved documents for new and existing dwellings there is an additional U value method added to L1B as requested by the double glazing industry. However this has been set at 1.6 W/m2K which is extremely stringent given that most A rated windows are at this level.

At one time it was proposed that conservatories less than 30m2 be included in this revision of the building regulations, but thankfully for anyone looking to build a conservatory next few years it looks like common sense has prevailed and conservatories under 30m2 still keep their exemption, conditional on all the existing external windows, doors and walls being retained or replaced, plus the property’s existing heating system not being extended into the conservatory.

Fortunately, Buckinghamshire based Energy Saving Trust members, Hazlemere Window Company has been manufacturing, supplying and fitting “A” rated aluminium windows since they became the first UK double glazing company to design and install a dualframe “A” rated aluminium window back in 2007. Since then Hazlemere have been supplying and installing both UPVC and aluminium A rated, B rated and C rated double glazed windows – all of which have been certified, tested and approved by the British Fenestration Rating Council who issue the Window Energy Ratings (WER’s). These energy saving, thermally efficient products have also been endorsed by the Energy Saving Trust. Download a Factsheet about the 2010 changes to Part L of the Building Regulations explaining how these affect you and your property now

If you would like free expert help and advice regarding the implications for your particular property of the higher energy performance standards required by any fenestration products you need to install in your property (be they replacement double glazed windows and doors or windows and doors for an extension/new build) on or after 1st October 2010, why not Freephone one of Hazlemere Windows and Doors experienced consultants on 08000 825825


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