Code for Sustainable Homes

Code for Sustainable Homes

The Code for Sustainable Homes is an environmental impact rating system for housing in England and Wales, setting new standards for energy efficiency (above those in current building regulations)[1] and sustainability which are not mandatory under current building regulations but represent important developments towards limiting the environmental impact of housing.



The Code was officially launched on 13 December 2006, and was introduced as a voluntary standard in England in 2007. It complements the system of Energy Performance Certificates[2] for new homes introduced in 2008 under the European Energy Performance of Buildings Directive,[3] and builds on the most recent changes to Building Regulations in England and Wales.

The Government-owned scheme is a successor to the Building Research Establishment's EcoHomes rating scheme first used in 2000. Although the Code currently applies only to newly built dwellings in England, the National Assembly for Wales recently announced a plan to adopt the code, earlier than its English neighbour, and Northern Ireland are required to achieve a code level 3 on all public sector homes from April 2008. In February 2008, Sustainable Homes Ltd were licensed to train assessors and Stroma Certification Ltd (Formally named Stroma Accreditation Ltd) won the license to training and certify code assessors. This was pushed through by communities and local government (CLG) as fears from a lack of assessors to cover demand.[4]

In March 2008, the UK government announced a mandatory requirement for all new homes to be rated against the Code from May 2008. No specific star ratings or assessments are set, but the rating means that every new home owner will know whether their home was built to higher standards than building regulations and what standards had been met. The rating also acts as an incentive to home builders to consider building to the Code's higher standards, whilst making the information routinely available will encourage consumers to be more demanding.

September 2010 saw compliance with the code become mandatory for new build dwellings for the public and private sector.

Technical guidance[5] is amended on a six-monthly basis, every April and October to reflect changes in materials and building techniques resulting from feedback from assessors and industry. There are also changes in the figures used relative to Approved Document Part L1A of the building regulations, for example the thermal standards set in Part L October 2010 make redundant the thermal standards of the Code for Sustainable Homes levels 1-3. This is representative of the Building Regulation's gradual improvement of thermal standards, level 4 Code thermal standards are set be part of the Building Regulations by 2013.


The code works by awarding new homes a star rating from 1 to 6, based on their performance against 8 sustainability criteria which are combined to assess the overall environmental impact. One star is entry level above building regulations, and six stars is the highest, reflecting exemplary developments in terms of sustainability.

The sustainability criteria by which new homes are measured are:

  • Energy and CO2 Emissions – Operational Energy and resulting emissions of carbon dioxide to the atmosphere (both of which have minimum standards that must be met at each level of the code)
  • Water H2O & Surface Water Run-off – The change in surface water run-off patterns as a result of the development– The consumption of potable water from the public supply systems or other ground water resources (each of which have minimum standards to be met at entry level)
  • Materials – The environmental impact of construction materials for key construction elements(no mandatory minimum standards).
  • Waste – Waste generated as a result of the construction process and facilities encouraging recycling of domestic waste in the home (no mandatory minimum standards).
  • Pollution – Pollution resulting from the operation of the dwelling (no mandatory minimum standards).
  • Health and Well-Being – The effects that the dwelling’s design and indoor environment has on its occupants (no mandatory minimum standards).
  • Management – Steps that have been taken to allow good management of the environmental impacts of the construction and operation of the home (no mandatory minimum standards).
  • Ecology – The impact of the dwelling on the local ecosystem, bio-diversity and land use (no mandatory minimum standards).


The Code is a 6 level rating system with credits in a broad range of categories from water use to occupant health. There are simple and inexpensive methods of gaining credits, like specifying compost and recycling bins, and costly methods such as installing solar photovoltaics.

In 2010 Code level 3 compliance is mandatory for public and private sector new-build residences, including flats and houses, effectively making redundant the use of code levels 1 and 2.

Currently, compliance with higher levels of the Code is voluntary, with a long-term view for step-change increases. However, landowners and agents are already selling sites with stipulations to build at a certain Code level.

The extra-over cost of building to Code Level 3 is valued between around £2000-3000, additionally the Code assessment costs around £2000 for a small project, the total cost of this is typically under 5% of a standard build.[6]

From 1st May 2008 it would be mandatory for all new homes to have a rating against the Code when houses are sold, it is mandatory for them to have an Energy Performance Certificate. If there has not been an assessment carried out, then a zero rating is given. This provides an incentive for developers to reach a higher rating. In fact more and more companies are including the Code and BREEAM in their corporate policy.

Code levels pertaining to energy require a Dwelling Emission Rate (DER) a certain percentage higher than the Target Emission Rate (TER) as set in Part L1A of the Building Regulations. October 2010 saw Part L TER standards rise equivalent to Code level 3. Since this change Code level 4 requires 25% DER improvement over Part L1A TER standards and code level 6 is 100% improvement i.e. thermally twice as efficient. It is also anticipated that the Building Regulations as well as the minimum mandatory Code level will continue to improve until the 2016 target of 'net zero CO2 emissions' per annum standard. Guidance is also available via the code simply explained published document to demistify the technical requirements.


The scheme was welcomed by the WWF for putting zero carbon development at the top of the industry agenda,[7] and by the Association for Environment Conscious Building for including 'whole house’ carbon emissions.[8] Despite these positive reactions, even a zero carbon building would only achieve Level 1 of the Code unless further measures are taken to comply with other requirements.[9][10] Other reactions were generally welcoming, but with some reservations.[11]

Views of the scheme were not always so positive; early drafts were heavily criticised by industry commentators, both for being unnecessary (due to it being apparently modelled on the existing EcoHomes scheme) and due to its contents.[12] In December 2005 the WWF representative on the Steering Group resigned "in despair" due to the failure of government to accept the Steering Group's advice and recommendations.[13] The Construction Products Association criticised the original proposals as being confusing.[14] The Sustainable Development Commission is keen that the standard is extended to cover existing homes, and covers this and other recommendations in its report 'Stock Take'.[15]

See also

Compare to


  1. ^ Office of the Deputy Prime Minister (ODPM publications), Building Regulations Explanatory Booklet, 2003
  2. ^ Communities and Local Government, Certification scheme and accreditation scheme standards, 2007
  3. ^ Defra, UK - Error page Archived 27 December 2010 at WebCite
  4. ^ Stroma - Stroma - Services for Building, Construction and Refubishment - Home | Front Archived 27 December 2010 at WebCite
  5. ^ Code for Sustainable Homes: Technical guide - 2010 - Planning, building and the environment - Department for Communities and Local Government Archived 27 December 2010 at WebCite
  6. ^ Code for Sustainable Homes: A Cost Review - Planning, building and the environment - Department for Communities and Local Government Archived 27 December 2010 at WebCite
  7. ^ Foundations are laid for a more sustainable future published 2006-12-13, accessed 2011-10-05
  8. ^ AECB congratulates the government Archived 27 December 2010 at WebCite
  9. ^ Housebuilder's Update: Drilling Down into the Code: Part 3 Mark Brinkley, published 2011-10-4, accessed 2011-10-5
  10. ^ Code for Sustainable Homes
  11. ^ Code for Sustainable Homes could be better Archived 27 December 2010 at WebCite
  12. ^ Archived 27 December 2010 at WebCite
  13. ^ Government fails to get UK’s house in order on Climate Change. | Article Search Results | WWF UK Archived 27 December 2010 at WebCite
  14. ^ Archived 27 December 2010 at WebCite
  15. ^ Stock Take: Delivering improvements in existing housing · Sustainable Development Commission Archived 27 December 2010 at WebCite

External links

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