Energy standards for new homes – the government gets tough

Last week’s government announcement of tough energy efficiency standards for new homes marked a decisive step away from five years of putting the housebuilder before homebuyer and planet.

Energy performance standards for new homes have been pretty much static since 2015 when the Conservative government scrapped the previous Labour administration’s 2016 zero carbon homes target in a bid to reduce red tape and the costs of complying with zero carbon standards for housebuilders. 

The growth of offshore windfarms has been faster than anticipated due to rapidly falling capital costs and is now economic without subsidy

Instead the sector got Help to Buy which fuelled bumper profits. This came against a background of increasing home buyer dissatisfaction with falling quality standards, Extinction Rebellion stalking the streets and most significantly the government’s target of net zero carbon emissions by 2050, upping the stakes from the previous target of reducing emissions by 80%.

• Read: Government launches consultation on energy regulations

The starting gun on the rebirth of tough new energy efficiency standards was fired by former chancellor Philip Hammond in March when he announced the Future Homes Standard which mandates the end of fossil fuel heating systems in new homes from 2025.

The launch of the Future Homes Standard consultation last week is the first concrete step towards this goal as it sets out the interim carbon reduction targets towards the 2025 target with these taking effect next year. These will be implemented through Part L of the Building Regulations which deals with energy; a consultation on the part that regulates new homes was launched at the same time.

The consultation proposes two reduction targets: a 20% cut in carbon emissions compared with 2013 Part L, to be achieved through fabric improvements, or a 31% cut. The government favours the latter target, to be met through the adoption of some low and zero carbon technologies together with fabric improvements. This would provide an early boost to the LZC (low and zero carbon) sector which will need a helping hand if it is to have any hope of meeting demand by 2025. The 31% target will have a much bigger impact on fuel bill reductions and consequentially a much shorter payback period. It also means the jump towards zero fossil fuels in 2025 will be easier to navigate.

There is much else to recommend the proposals in this consultation which address much more than a simplistic headline carbon reduction target. This includes the scrapping of a loophole that has allowed housebuilders to continue building homes on large sites to old energy regulations despite newer, tougher standards taking effect. 

Called transitional arrangements, it meant housebuilders could build all the homes on a development site to the regulations in force when they started work on the first house regardless of how long this would take. This anomaly meant someone buying a new house on a site that had been developed over many years could unwittingly end up with a much less energy-efficient home than one built at the same time on another site. Transitional arrangements also meant the carbon reduction ambitions of later iterations of Part L were stymied.

The consultation also includes the first steps towards improving the as built performance of new homes.

The poor energy performance of new homes when compared with the design intent has long been a concern to many in the industry and government. The Part L consultation proposes that housebuilders provide photographic evidence in a bid to get round the problem – it is very hard to check insulation levels and other energy-saving measures once these are covered up. The consultation also proposes that all new homes must be subjected to air pressure testing rather than just a sample. 

Some aspects of the consultation will be welcomed by housebuilders, including the proposal to scrap local carbon reduction targets which have been implemented through the planning process. This has long been a bugbear of the sector as it creates a postcode lottery of differing energy standards.

The problem of overheating in new homes promises to be tackled in a consultation for launch later this year and will be blended into 2020 Part L.

The carbon reduction targets in the consultation are predicated on the widescale adoption of heat pumps, a very different strategy from the previous zero carbon trajectory which relied on complex carbon offsetting rules to work. This change is thanks to the wind power dividend; the growth of offshore windfarms has been faster than anticipated due to rapidly falling capital costs and is now economic without subsidy. The 2025 target relies on this trend continuing as demand for electricity increases to power electric vehicles and homes. There needs to be a parallel growth in energy storage systems to take full advantage of the growth in wind power. There is a case for government help on the grounds that subsidies have been so successful in stimulating the renewable energy sector. The country is going to need this low carbon electricity to fulfil the ambitions of a consultation due out later this year which aims to reduce carbon emissions from existing homes. In all likelihood this will also rely on the adoption of heat pumps. Tackling the existing stock is the only way to hit the 2050 zero carbon target and will be the acid test of how far this government is prepared to go.

Thomas Lane is group technical editor at Building