Urgent action demanded to improve SAP for calculating energy use of new homes
The government’s tool for calculating the energy performance of new dwellings cannot adequately meet the challenges of delivering low-energy and zero-carbon houses, concludes a new report.
A six-month study undertaken by the Zero Carbon Hub, due to be published next week, concludes that the Standard Assessment Procedure (SAP) now used to calculate the energy performance of new dwellings and demonstrate compliance with Building Regulations is not adequate in its current form.
Compliance tools are used to assess a design to see if it meets the energy criteria set out in regulations and often steers designers and the products and systems they specify. However, should the compliance regime result in a poor reflection of reality then there is a risk that carbon emissions and energy use will be higher than expected.
The report suggests that urgent action is required to ensure that a compliance tool fit for purpose is developed to meet the government’s target for all new homes to be zero carbon by 2016.
It proposes that the development of a tool could be financed by government, or through the private sector with government maintaining ownership of the policy.
David McEwan (Glasgow) comments on 9 Jul 10 4:44 pm:
‘Although it’s unclear as to whether this report refers to SAP 2005 or the Part L 2010 version (confusingly termed SAP 2009), it raises an important question; why is the Government continuing to spend money expanding the capabilities of SAP, when other alternative tools are already available in the form of SBEM and DSM?
These existing non-domestic compliance methods can equally apply to domestic properties and offer tools which are flexible enough to accommodate different levels of building complexity – the kind of complexity required in new housing to achieve zero-carbon, with all the associated passive design strategies, clean-technology and renewable energy sources.
The Part L 2010 version of SAP has already moved to a monthly calculation method, the same as SBEM. Surely opening up the choice of tools available for domestic dwelling compliance allows more flexibility – enabling designers to pick the tool sufficiently complex for the building in question.
At this time when the Government is asking for ideas on how to save money, surely making use of existing tools that Energy Assessors are already familiar with is the most cost effective way forward without the need for more government investment?’
