The government’s proposal to accredit housebuilders as part of its Part L consultation should raise standards

The government’s Part L consultation marks the first serious attempt to tackle the gap between energy efficiency in the design and the actual performance of the building upon completion.

It proposes housebuilders should have formal, quality assurance accreditation and follow a new set of standards for how homes should be designed, built and tested. Any housebuilders that opt out have to build homes 3% better than the proposed 8% carbon emission reduction target. This is intended to ensure those homes are nearer the 8% target than they might otherwise have been.

The proposal should be welcomed as there is no point in setting targets if most homes don’t, on completion, get anywhere near the aim

The proposal should be welcomed as there is no point in setting targets if most homes don’t, on completion, get anywhere near the aim.

Tests reveal that many new homes fall well short of design intent - a Joseph Rowntree Housing Trust development called Elm Tree Mews was losing 54% more heat than designed.

Energy Saving Trust tests on heat pump installations found over half were consuming more energy than allowed for in Part L energy calculations. This was down to poor quality installation.

But for the proposal to work a publically available specification will need to be drawn up. This will cover issues including the robustness of energy calculations, site processes including ensuring the specification was followed, the competency of workers and guidance on testing. Housebuilders would also need to achieve a quality standard such as IS09001.

The proposal has many benefits. A standard that formally sets out best practice can only be a good thing. Quality accreditation should raise standards and mean carbon emissions from new homes could be dramatically lower than at present.

The housebuilding industry may bleat about the costs of accreditation and training but remember they only have to realise an 8% reduction in carbon emissions in 2013 whereas the rest of the industry will probably have to cope with 20%.