Whilst Ecohomes in Scotland, and the Code for Sustainable Homes in England and Wales attempt to establish criteria and technical guidance for improving the overall sustainability of new homes, there are additional initiatives that focus specifically on driving the low carbon agenda. These have the ambition of ensuring that all new homes built from 2016 onwards are Zero Carbon Homes and add no new carbon to the atmosphere.
The UK Government set out its vision for zero carbon new homes in 2006 in a consultation document entitled Building a Greener Future: Towards Zero Carbon Development. The report sought views on the Government's proposals to reduce the carbon footprint of new housing development. It explored the relationship between the planning system, the Code for Sustainable Homes and Building Regulations in delivering the ambitions for zero carbon homes and it proposed a timetable for revising and progressively tightening the Building Regulations (Part L Conservation of Fuel and Power) in 2010 and 2013 so as to reach zero carbon development in all new housing in England & Wales by 2016.
Since the launch of the 2016 target, there has been much debate as to the definition of a zero carbon home. The original definition was for the home to deliver a 70% reduction in emissions compared to current homes; this would require a combination of high energy efficiency and on, or near-site, renewables. The remaining 30% new carbon emissions, plus an amount for non-regulated electricity use such as by appliances, would be supplied by directly connected renewables. This definition soon became widely recognised as economically unachievable and very few such homes have been built.
The Zero Carbon Hub, which was set up by government and industry to help deliver this challenging target, has been working to find the most technically achievable and cost-effective way to deliver the target. The zero carbon target has been broken down into three parts:
- A high level of insulation and air tightness known as the Fabric Energy Efficiency Standard (FEES)
- Efficient heating, hot water and lighting known as the Carbon Compliance Standard (CCS)
- The remaining emissions to be dealt with via “Allowable Solutions”. These will probably include the option to go for higher standards of the FEES and CCS, as well as onsite and offsite renewables. Government has yet to fully define Allowable Solutions.