Flawed energy efficiency modeling is the reason many green buildings fail to live up to expectations on energy efficiency, according to a U.K. researcher.
David Coley, a University of Bath specialist, led a team that surveyed 108 architects, engineers, and energy consultants who routinely use energy performance models. They asked participants to look at a typical British semi-detached home recently updated to meet current building codes. Then they asked test subjects to rank which improvements made the most difference to energy performance.
Their answers didn’t match up with reality, suggesting a performance gap between modeling and the real world. There were cases where the modelers produced a savings measure that was more than the energy use of the house.
Energy models showing unreasonable results are evident at the preliminary stage on half of projects going through the LEED certification process, according to a U.S. Green Building Council official. Designers have a tendency to accept outputs without evaluating the reasonability of the results, she said.
Part of the reason for the performance gap is that modelers do not usually go onsite to see how the building operates and compare that to the design. Typically there is no expectation that they’ll even talk to the building manager at year one and ask how energy usage compares with the original model.
Related Stories
Codes and Standards | Oct 16, 2015
Appellate court enacts nationwide stay on controversial expansion of Clean Water Act
New EPA rule suspended until court cases settled.
Codes and Standards | Oct 9, 2015
New California law means commercial building benchmarking program will be implemented
Multifamily housing to be included, a first for a U.S. state.
Codes and Standards | Oct 2, 2015
New ASHRAE guideline for commissioning existing systems and assemblies
Focuses on optimum facility and system operation.
Codes and Standards | Sep 18, 2015
New RELi standard addresses disaster resilience
Based on LEED model, may help lower insurance rates
Building Materials | Aug 28, 2015
Structural steel buildings specification available for second public review
Next year's specification open for comments until Sept. 21
Energy Efficiency | Aug 28, 2015
North American Passive House Network e-book explains Passivhaus, net-zero techniques
Free guide includes spotlight on individual projects
Windows and Doors | Aug 28, 2015
Newly formed group challenges Florida building code
Window, door companies oppose provisions that raise costs
Codes and Standards | Aug 28, 2015
New Orleans becoming a model for climate resilience only 10 years after Katrina
The city has moved ahead with resilience strategies that may become a model for other communities
Codes and Standards | Aug 21, 2015
Illinois governor vetoes bill that would restrict condo owners’ rights
Bill would have made it harder to sue for building flaws
Codes and Standards | Aug 21, 2015
Post-Katrina roofing codes creating more resilient buildings on Gulf Coast
Ten years after storm, notable progress on stronger roofs, IBHS says