Reviewing the code for sustainable homes

Written by Sustainable Homes

The Code for Sustainable Homes has been in active use for the past two years and looks set to continue into the future. Experience gained by the regulators and housebuilders coupled with the UK’s necessity to reduce carbon emissions, means that the time has come to updated the code. This article will touch on how the code works, recent changes, proposed changes and observations from those training to become qualified Code Assessors on Sustainable Homes’ training courses.
    
Very briefly, the code rewards sustainable features of a home such as energy efficiency, materials used and ecological value. Each feature included in the design results in points being awarded, which when added determine which “Code Level” the home has achieved. Accumulating 36 points means that level 1 is achieved and 90 points means that code level 6 is achieved. Formally qualified code assessors collate evidence to prove that features have been correctly put in place.
    
There are some sustainability features that have to be included. These are low dwelling carbon emissions, water efficiency, surface water management, domestic waste storage and site waste management plans.

Recent changes
The most notable of the recent changes is the methodology to calculate the water efficiency of new dwellings. This is an interesting issue because this is the first part of the code that has become part of the building regulations (it’s now included in Part G). It must be remembered that one of the reasons for introducing the code was to signal future changes and this has indeed happened.
    
Recent flood events have highlighted the importance of surface water management in the UK. This issue is addressed in the code and has been recently reinforced. The requirement to carry out accurate hydrological calculations still remains but some specific exemptions have been identified. This is not an easy way out for builders because these exemptions themselves must be justified with detailed evidence.
    
On the subject of evidence, the last major recent change has been the type of evidence required. Up until recently, the code has detailed specific evidence requirements. There is now more flexibility in the types of evidence required but the evidence required still has to be rigorous of an auditable quality as reflected in the term “detailed documentary evidence”.
    
The recent changes have been relatively minor compared to those that have been proposed. The main proposed changes have focused on the energy category. There will no longer be reward for reaching the code level 3 carbon emission requirement as this will be mandatory in order to comply with the new building regulations. Instead more points will be available for concentrating on the fabric of the building to reduce space heating demand in the first place. This will mean that high levels of insulation, air-tightness and thermal bridging will still be rewarded. An interesting addition is the inclusion of space cooling demand to ensure that overheating does not become a problem in the future.
    
Also in the energy section are specialist exceptions to home office and cycle storage requirements as well as a new issue to reward provision of smart meters which allow householders to continual observe, and hopefully reduce, their energy usage. It is proposed to remove the requirement for energy efficient light fittings as they will also be a requirement of the new building regulations.
    
Other proposed revisions include dropping the mandatory requirement for site waste management plans and standardising the criteria for security. Access requirements for household waste storage, compost facilities and private space will be amended to avoid duplication across the issues and to align with lifetime homes.
    
These changes will exercise the people who will be building homes but will also clarify many of the issues that have emerged in the last two years. Code building has been mainly within the social housing sector. However in the last six months we have seen more and more private developers qualifying as code assessors. They are predominantly driven to do so by local planning permission requirements. We are also seeing a small but growing number training up simply to be ahead of anticipated changes in building regulations.

Product development

As well as turning up in local authority requirements, the code has also prompted technical development of products. We have seen an increasing number of products advertising code compliance compared with two years ago.
    
The other thing that has been prompted by the code is the whole debate on sustainability. People are now realising that new build contributes a relatively small proportion of UK environmental impacts. The ultimate prize is to tackle the impact of existing buildings. Developments on this front are eagerly awaited.
    
Nevertheless, until sustainability initiatives for existing build emerge, the code will continue to stimulate debate and technological development and provide more sustainable housing for the UK.

For more information
Sustainable Homes trains code assessors under licence from BRE, in addition to training on other sustainable housing standards. It also runs a sustainability benchmarking scheme for housing providers, called SHIFT, please see www.sustainablehomes.co.uk