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Meeting the challenges of Part L in Wales

NHBC Foundation publishes new guidance for builders

House builders and designers who operate in Wales will today benefit from new guidance by the NHBC Foundation on how to meet the challenges of Part L.

With the zero carbon standard for new homes coming closer, house builders are ever-more focused on achieving energy efficiency. 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.

The NHBC Foundation is publishing two guides: ‘Part L 2014 – where to start: An introduction for house builders and designers – masonry construction – for Wales (NF64)’ and ‘Part L 2014 – where to start: An introduction for house builders and designers – timber frame construction – for Wales (NF65).’ Similar guides are also available for Part L 2013, England.

Since last year new Approved Documents for conservation of fuel and power have been in operation in Wales, which have stepped up the level of performance required. For the first time, they differ from the Approved Documents in England.

The new guides will help house builders understand approaches to achieve compliance with Part L

Aimed at SMEs in particular the new guides will help house builders understand the variety of approaches that can be used to achieve compliance with Part L, as well as the types of floor, wall and roof constructions that can be specified.

The guides include detail on the topic of thermal bridging, such as the heat loss which occurs around window openings and at the junctions between building elements. In recognition of the amount of energy that can be wasted through thermal bridging, the guides include good practice details which show clearly the critical features of good design and construction.

Neil Smith, Head of Research and Innovation, NHBC, said: “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 builders operating in Wales who may not be as aware of the range of options available to them to satisfy Part L.”

Carl Sargeant AM, Welsh Government Minister with responsibility for Building Regulations: said: “The Welsh Government recognises the technical challenges that builders face in this area, which is why we welcome the National House Building Council’s move to publish new guidance on Part L in Wales.”

To read and download the guides, please visit