Performance Gap Project - End of Term Report Launched

Monday, July 7, 2014

The Zero Carbon Hub has today released its End of Term report on the Design versus As-Built Performance Gap project. This report provides industry and government with clear recommendations to close the Performance Gap. It follows on from the Interim Report published July 20131 and the Evidence Review Report published March 20142.

To download the End of Term report, click here.

The Performance gap can arise in a number of ways within the overall house-building process and, if significant and widespread, represents a major risk to government, industry and consumers and may lead to increased costs to the occupant. Tackling this therefore continues to be a significant and serious factor as the Hub develops the Zero Carbon Definition.

The report proposes a broad number of solutions to close the Performance Gap, grouped into themes of: Energy Literacy; Improving Quality Outputs; National Compliance Method and Regime; Demonstrating Performance; and Continued Evidence Gathering and Dissemination. 

Four priority actions are identified for industry, including investment into R&D, training and the development of an industry owned Construction Details Scheme, providing ‘assured’ as built energy performance for common fabric junctions and systems.

Four further priority actions are identified for government, including changes to the compliance regime and actions to stimulate industry investment. A clear signal is needed from the government that industry is expected to act now to address the Performance Gap.

Commenting on the report, Rob Pannell – Managing director of the Zero Carbon Hub, said:

“This report sets out a clear set of recommendations for both government and industry to address the Performance Gap. The range of these solutions shows the scale of the challenge, but our priority actions provide a clear route to tackle it.

As we approach the zero carbon target, housebuilders are producing higher performing homes and need to be confident that they truly perform as intended. Government needs to know that homes play their vital role in the national carbon reduction target.

We believe that industry is entirely capable of closing the Performance Gap themselves, with some refinement to the compliance regime to catalyse it. With the completion of this report, we look forward to helping to move the proposals forwards, up to 2020 and beyond.”

Reaction from wider industry

Nigel Ingram, Director of Development, Joseph Rowntree Foundation:

“Joseph Rowntree Housing Trust have developed a methodology over the years for trying to ensure designs & concepts are delivered effectively. Some might reply this is just good Project Management practice but it boils down to ensuring a collective understanding is arrived at by the key parties at the appropriate stage of a project. This is easy to say but often difficult to actually achieve, as who these key parties are, can be subject to debate - therefore this Performance Gap evidence is critical as it shines a light on who/what these key links in the construction chain are."

Michael Black, Development Director, Bovis Homes Ltd:

“If we are to address any performance shortfall then it is critical that the SAP Assessment tool and the SAP verification process is both robust & auditable. Those undertaking U-value & Psi-value calculations need to be subject to improved training & rigorous accreditation to ensure accuracy & consistency of those details. We strongly endorse the Report’s recommendations in this regard and for the development of robust Construction Details to underpin such improvements in performance.

Steve Shanahan, Vinci Technology Centre UK Ltd:

“Vinci Technology Centre UK LTD is please to be associated with the Performance Gap project, and welcome the recommendations put forward within this ‘End of Term’ report. We will take on board the evidence produced within this report and will use it to ensure we continue to assist in the effective delivery of sustainable projects. We would like to take this opportunity to thank the Hub for undertaking such a crucial piece of work.”

Adam Mactavish, Operations Director, Sweett Group:

“This work has proven to be really valuable and should benefit both the industry and homebuyers.  The engagement process delivered a raft of suggestions, directly from the industry, for reducing the Performance Gap. Importantly it also identified some very achievable savings can be achieved now by looking at procurement and site practice. These savings are very cost effective and will help reduce the cost of owning a new home.”

John Sinfield, Managing Director –Northern Europe, Knauf Insulation:

“Knauf recognise that there is a competitive advantage of being able to guarantee the robustness of our product performance in use. Our challenge is to make enough commercial benefit to reward early innovators so that the sceptics do not win out. We are at the limits of our current testing capabilities, which is a challenge for the entire supply chain.”


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Notes to Editors

Closing the Gap Between Design and As-Built Performance – Interim Report 

Closing the Gap Between Design and As-Built Performance – Evidence Review Report