Green for Growth: Zero-Carbon Homes

In 2006, the Labour government gave the housebuilding industry 10 years notice to make its products zero-carbon. This ambitious requirement was launched as part of the Code for Sustainable Homes, and included interim carbon reduction targets along the way: 25% reduction in emissions in 2010 and 44% in 2013. Zero-carbon was going to be expensive – adding up to £40,000 per home – but the argument was that the industry would find ways of reducing these costs as the 2016 deadline approached.

About the only aspect of the zero-carbon requirement welcomed by the industry were the clear carbon reduction milestones along the way. This gave manufacturers confidence to invest in zero-carbon-friendly products and galvanised housebuilders into action. A collection of odd-looking homes sprung up at BRE’s innovation park at Garston, Merseyside. Zero-carbon made the industry innovate.

That confidence has taken a battering since the last election. The chancellor George Osborne changed the definition of zero-carbon in the March 2011 Budget so housebuilders would no longer have to provide zero-carbon energy for domestic appliances, just heating, fixed lighting and hot water. Confidence has been further undermined by cuts in feed-in tariff rates for renewable technologies.

The biggest wobble, however, came from the 2013 Part L consultation. Instead of the 25% cut in carbon emissions over 2010 as proposed in the Code for Sustainable Homes, the government favoured an 8% cut, citing the election pledge not to place additional burdens on housebuilders during this parliament. This means that housebuilders face a much bigger jump in 2016 to keep the zero-carbon deadline on track. Additionally, the details of allowable solutions, the mechanism for handling how carbon emissions are mitigated off site, has yet to be finalised. The Zero Carbon Hub put forward proposals for managing this process in July 2011 but the government has yet to respond.

The carbon reduction jump needed in 2016 to keep the zero-carbon policy on track may be too big for the housebuilding industry to cope with. This means the date could be shifted to 2019, which would align with the date for all other buildings to be zero-carbon. Either way, the industry wants to know now. “We do need clarity now,” says Dr Elizabeth Ness, group sustainability director at Crest Nicholson.

“We are hoping that, whatever is in the 2013 regulations, it will also give us a future trajectory, as uncertainty is very bad. It doesn’t let us plan properly when it comes to buying land and it is bad for supply chains as they need certainty to invest.”

The government is watering down the zero-carbon targets for cost reasons. According to figures from the communities department, building a three-bedroom semi on a brownfield site would cost 4% extra if carbon emissions were cut by 25% over 2010 Part L and 15% extra to meet the new definition of zero-carbon. Meeting the target set to the original definition of zero-carbon would cost an extra 29%. But some housebuilders and designers have developed low and zero-carbon solutions that cost very little more than a home built to Building Regulations.

This demonstrated that zero-carbon homes are financially viable and makes the case for the government to press on with the zero-carbon agenda. The industry needs a clear deadline for all new homes to be zero-carbon, plus interim targets and workable solutions. Whether this is by 2016 or later, the government needs to bring clarity to the table now.