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NHBC Foundation publishes invaluable new guidance on meeting challenges of Part L

With the zero carbon standard for new homes just two years away, house builders are ever-more focused on achieving energy efficiency.  The next step in the journey was set with the latest changes to Part L issued by Government earlier in the year as the 2013 edition of Approved Document L1A, which sets rigorous energy standards for new homes in England.

Complying with Part L – conservation of fuel and power in new dwellings – is one of the most complex challenges faced by the house-building industry, so today the NHBC Foundation is publishing two new guides to help house builders and designers understand what is now needed.

The guides, which build on NHBC Foundation guidance first published in 2011, cover the two most common forms of construction – masonry and timber frame.

New in these guides is greater detail on the topic of thermal bridging, such as the heat loss which occurs which occurs around window openings and at the junctions between building elements.  As a first stage in the design process, house builders and designers must now decide how to deal with thermal bridging, before other specification choices can be made in relation to insulation, airtightness, services and renewables.

In the foreword to the report, Stephen Williams MP, Minister for Communities, commented: “The Government recognises the technical challenges that builders face in this area, which is why these publications from the National House-Building Council are to be welcomed.”

Neil Smith, Head of Research and Innovation, NHBC, said: “The guides provide a useful starting point for designing new homes to Part L 2013.  Many in the industry struggle to get to grips with the complexities of Part L and we hope these new, clear and simple guides help will help to build an understanding.

“Presented mainly as tables and construction details, this guidance should be of particular use to smaller firms who may not be as aware of the range of options available to them to satisfy Part L.”

To read and download the guides, please visit