The GHA has developed a significant policy presence since its launch, and we are continuing to grow our influence with the new government. Our current work is focusing on the need for as-built performance measurement, and simpler, more-effective regulation. We have also started to work on wider policy aspects of good homes relating to planning and localism, including health, well-being and sustainable lifestyles.
Using the practical experience of its members and associated research work, the GHA is lobbying Government and land owners to encourage fully sustainable house building through legislation and specification. Our current policy activities include:
As-built performance measurement - the 'performance gap'
The GHA is leading the campaign for home performance assessment to be based on measured as-built performance, rather than design targets/intent. This is particularly important in the case of the energy efficiency of new homes, where the performance gap – the difference between actual as-built performance and the design target - has been shown to be up to 120%. The GHA is involved in the Zero Carbon Hub group that discusses how performance measurement could be included in the Building Regulations requirements, and has been actively promoting the inclusion of as-built performance measurement in the zero carbon definitions. GHA Developer Members are also required to monitor the performance of their projects post-completion.
Making as-built performance measurement mainstream relies on the development of robust and cost-effective testing methodologies. The GHA has been active in helping to trial, develop and promote these methodologies through its monitoring programme. Please click here for further information.
Zero Carbon definitions
The GHA was involved in preparing an input to the original definition for zero carbon homes - see our paper below – and GHA members have voted on the usability of the definition at their Christmas debate every year since 2008 - see the results of the debates below. In particular, the GHA has been active in promoting the inclusion of as-built performance measurement in the definition.
Code for Sustainable Homes (CSH)
The GHA has been a member of the CSH Technical Working Group since 2007, and has worked diligently to try and ensure that the Code will actually deliver truly sustainable homes. During 2008-09 we found problems in several areas - energy, water and materials - and highlighted these in 3 detailed papers, all available below.
The energy paper highlights our Members' experience of implementing the energy requirements at Levels 3 & 4, suggesting that there are some inconsistencies in the Code, that the % reduction methodology can be unhelpful for some building types, and that there are significant unintended consequences arising from the fuel factors defined in Building Regulations. These issues were recognised by DCLG and the points were examined and addressed as part of the 2010 review of Part L of the Building Regulations.
The water paper highlighted problems with this section of the code and the water calculator, which were also acknowledged by DCLG and were under consultation as part of the Part G 2010 review. The water calculator has now been updated but inapporapraite rainwater harvesting is still being specified for higher levels of the Code.
The GHA also highlighted some difficulties with using BRE's Green Guide to Specification in the materials section of the Code - see the section below for more info.
The GHA has been a champion of the fabric first approach as a means of achieving low-energy buildings that are robust in the long term. GHA Developer Members are required to meet a testing low-energy standard - based on as-built measured performance - as a condition of their membership. We are delighted that this approach is now incorporated into the zero carbon homes definition in the form of the Fabric Energy Efficiency Standard.
BRE's Green Guide to Specification
The GHA prepared a critique of BRE's Green Guide to Specification, written by Neil May of Natural Building Technologies and Gary Newman of Plant Fibre Technology. The critique highlighted a number of concerns raisd by GHA members related to the use of the Green Guide, particularly:
- transparency of the LCA data
- build up of the data into Generic Profiles
- potential negative impacts on whole-house performance
- use of the Green Guide as a Planning or Code requirement
Many of these criticisms remain valid today; a copy of the critique and an update following recent responses can be downloaded below.
Part L Review
The GHA was asked to input into working groups leading up to the consultation process for Part L.
Energy Efficiency Partnership for Homes - EEPH
The GHA was involved in the new build branch of EEPH - see more at www.eeph.org.uk