The Code for Sustainable Homes
is the Government’s national standard for new housing, even though it is optional. It became effective in England in April 2007 and a Code rating for new homes became mandatory in May 2008. It is not compulsory for every new home to be built to the Code
, but each home must contain a rating against the Code
It incorporates all key Government sustainability targets into one standard, measuring sustainability against categories such as energy and CO2 emissions, water, materials, surface water run-off, waste, pollution, management, ecology, and health and well being.
A home is given a sustainability rating that ranges from one to six stars, where Level One
is a modest improvement on minimum regulatory standards and Level Six
is a zero carbon home with an exemplary level of sustainability performance.
In November 2010, the Government made changes to the Code For Sustainable Homes to bring it into line with new regulations such as the Part L of the Building Regulations as well as to simplify the Code.
Assessments are carried out in two phases:
• An initial assessment and interim certification is carried out at the design stage. This is based on design drawings, specifications and commitments, which results in interim certificate of compliance
• A final assessment and certification is carried out after construction. Based on the design stage review, this includes a confirmation of compliance including site records and visual inspection.
Shortly after the introduction of the Code
in 2007, developers of demonstration homes on the BRE Innovation Park
were among the first to try building to the Code
’s higher levels and a four-part Information Paper produced by BRE explains the lessons learnt.
The experience gained from the Innovation Park provided lessons in terms of building fabric, energy and ventilation, water economy and materials. The Information Papers
provide some of these findings:
• Simple house designs are easier to make airtight, as are large panel construction systems with few joints
• Windows and doors must be specified and installed for air tightness, day lighting and solar gain as well as thermal performance and sustainability
• Achieving Levels Five and Six requires the use of ‘renewable’ energy, either generated communally, or through micro-generation at each house. A range of energy technologies was installed on houses at the Park
• Appropriate shading, thermal mass and ventilation can minimise overheating
• Water use can be reduced while minimising the effect on the end user by using aerated showers and taps to increase perceived flow rate without increasing water use
• Careful specification of white goods can save water and earn credits under the Code
• Water butts that collect water from the roof are an effective, but must be fitted with functioning overflows.