There is a widely held belief that there are currently two definitions as to what constitutes zero carbon; the Treasury has one version and the Department for Communities and Local Government (DCLG) has another.
But John Alker of the UK-GBC says: ‘For all intents and purposes there is only one, and that is as laid down by the DCLG in its Code for Sustainable Homes’.
Under the DCLG code, to attain Level 6 status (that is to be defined as zero carbon), in addition to achieving Standard Assessment Procedure (SAP) 2005, homes must be built so that ‘net carbon dioxide emissions resulting from all energy used in the dwelling are zero or better’.
In the latest budget the Treasury promised to exempt zero-carbon homes from stamp duty, but it did so before the technical guide for the DCLG’s code had been published.
The original code allowed for off-site renewables; however, the Treasury made a U-turn and demanded that all renewable energy should be self-generated, and not from the National Grid.