How Carbon Negative Homes Could Change the House Building Industry
St Modwen Homes launched its first set of affordable carbon negative homes in Copthorne at its new development of Heathy Wood last year. Although other house building developers have created carbon negative homes before, St Modwen Homes is the first major housebuilder to have built affordable ones. Working alongside British Gas, this development has seen people’s energy bills reduced by 79%, as well as a reduction in CO₂ emissions by 125%.
Carbon negative homes essentially produce more energy than they consume. They are so energy efficient that they do not cost as much to heat and light as traditionally built homes. British Gas kitted these homes out with Hive smart home technology to help reduce energy bills even further and as a way of showcasing how smart heating technology can help consumers become more energy savvy.
Steps were taken in construction to reduce the amount of embodied carbon, which is carbon emissions trapped and associated in a building’s lifecycle. Low carbon concrete was used to get partly around this, which is just one way in which building developers could start to implement change in their future projects. It’s not simply enough for households to limit their emissions; the way buildings are constructed and the carbon emissions associated with that, i.e., embodied carbon, needs to be drastically reduced.
St Modwen Homes estimated that these carbon negative houses will be able to reduce a household’s energy bill by 52% compared to a standard new build. When compared to the UK average, this increases to an impressive 79%. Having been completed in May 2022, these two homes came at the right time when energy prices were rapidly rising, even before the Energy Price Guarantee was introduced.
Other developers should take stock of how they construct and design their new homes, taking inspiration from the modern technology used and installed. Besides the useful solar panels, solar batteries, EV chargers and air source heat pumps that were included, they also made use of smart hot water tanks and heat recovery from both ventilation and waste water. The fabric of the homes included improvements to the insulation and ventilation as well, creating warmer homes. Air tightness was also 10 times higher than industry standards, reducing the opportunity for energy leaks and wasted heating.
Since the government scrapped the Code for Sustainable Homes back in 2015, there hasn’t been any need for house building developers to build eco features into homes. Instead, it was considered too costly to do so and removed several hoops to jump through. The scheme awarded developers points towards implementing environmental features to their new developments, whether they decided to sit just above Building Regulations or really showcase exemplary standards of ecological living.
With more developers like St Modwen Homes going out of their way to build carbon negative homes that are affordable, more people can benefit. Living in a sustainable home doesn’t have to be for the elite or those with the most money. The house building industry has a lot of work to do to reduce operational carbon, i.e., emissions from living in a building, as well as embodied carbon to really make a difference. If the standards are raised or implemented more heavily by government, real change will be seen en masse.