The Chartered Institution of Building Services Engineers (CIBSE) supports the UK Green Building Council call for the wider roll out of display energy certificates contained in its report ‘Carbon Reductions in Existing Non-Domestic Buildings’.

“There is now a clear industry consensus around making more use of Display Energy Certificates to identify potential energy and cost savings,” said Hywel Davies, CIBSE’s Technical Director.

To support the publication of the report, CIBSE has completed an analysis of the first 45,000 display energy certificates, and in particular the benchmarks used to calculate the DEC ratings. The review has looked closely at the spread of ratings across the 29 different benchmark categories, and found that the benchmarks are generally fit for purpose and accurately reflect the performance of the building stock. In particular, the benchmarks for schools and for offices are both within 2% of the median value for all the schools and offices rated, which demonstrates a high level of accuracy.

The report’s recommendations provide the basis for extending the use of Display Energy Certificates to commercial buildings. The report calls for a soft start to the introduction of non-domestic DECs to ease administrative adjustment and allow for data collection and further benchmark refinement before the results are disclosed and displayed.

The report also calls for landlords of multi-let commercial buildings bigger than 1,000sq m to be required to obtain a Landlord Energy Statement (LES), which details energy use in, and carbon emissions from, offices.

“These recommendations pave the way for the roll-out of DECs to non-domestic buildings, and help smooth out the relationship between landlord and tenant by clearly defining the areas of responsibility regarding the energy use of commercial properties ,” said Hywel Davies. “The CIBSE review of the benchmarks shows that in all but a handful of cases the benchmarks are fit for the job and provide accurate measures of the efficiency of the buildings on which they have been used.”