Building modelling professionals are to blame for the difference between a building's estimated energy consumption in design and how much it uses in operation, researchers claim.
Academics at the University of Bath’s architecture and engineering and psychology departments said it was vital to find the reasons behind this common performance gap, which resulted in non-domestic buildings using up to twice as much energy and emitting twice as much carbon dioxide as predicted.
The research focused on the building modelling stage of the design process and involved interviews with more than 100 professionals about energy-related aspects of a building, from the insulation in the walls to heat settings.
The professionals failed to agree on the aspects that were important and those that were not, or on how much difference to the energy bill changes would make. Professor of low-carbon design at the university, David Coley, said: ‘The inaccuracies of building modelling professionals have severe financial and environmental implications for the government’s global warming targets, as well as building owners who are purchasing homes and other buildings that are sold to be energy efficient but are not.’
However, sustainability consultant Niall Enright said that the study’s conclusions showed a ‘complete lack of understanding’ of the purpose of modelling, and its constraints. Modellers have to use the Standard Assessment Procedure (SAP) tool, which is very generic, and usually do not know a building’s final occupants, he noted.
‘The purpose of modelling at the design stage is to improve the quality of materials and equipment selection. To blame modellers for the performance gap is completely wrong,’ he said. ‘Occupiers of a new building should ensure heating, lighting and ventilation systems are set to meet their requirements.’
John Alker, campaign and policy director at the UK Green Building Council, said that solving the performance gap was a shared responsibility between everyone involved in designing, developing, constructing, operating and occupying a building.
