Code for Sustainable Homes
Since 2007 the developer of any new home in England can choose to be assessed against the Code. From 2008 it was mandatory for all new homes to be rated against the Code and to include a Code or nil-rated certificate within the Home Information Pack. Even though the requirement for the Home Information Pack for property sales was suspended in 2010, an Energy Performance Certificate is still required.
There are six levels of the Code, with mandatory minimum standards for energy efficiency at each level. Level 1 represents a 10% improvement in energy efficiency over the 2006 Building Regulations. Level 6 would be a completely zero-carbon home (heating, lighting, hot water and all appliances).
Improvements in the energy efficiency of new homes of more than 25% compared to 2006 regulations (Level 3 of the code) would probably require some form of low- or zero-carbon energy generation, either by individual buildings (eg dedicated solar water heating) or by whole developments sharing a source of low carbon generation (eg wind turbines).