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 | Mar 29, 2015
Elevator shafts a major source of heat loss in New York City
A typical New York apartment building loses thousands of dollars worth of energy every year from leaky elevator shafts that vent warm air at the top of the building and draw in cold air at the bottom, according to a new Urban Green Council report.
Green | Mar 22, 2015
6 myths holding back green building
Sustainable design has proven benefits, so why isn’t it more widely adopted?
Multifamily Housing | Mar 16, 2015
New Jersey Supreme Court puts control of affordable housing agency in the courts
The court said the state’s affordable housing agency had failed to do its job, and effectively transferred the agency's regulatory authority to lower courts.
Codes and Standards | Mar 16, 2015
San Jose adopts bird-friendly building standard
The standard includes avoiding large chunks of transparent or reflective glass and adding fritting.
Codes and Standards | Mar 12, 2015
Energy Trust of Oregon offers financial incentives for net-zero buildings
The organization is offering technical assistance along with financial benefits.
Codes and Standards | Mar 10, 2015
Real estate interests push Congress for Census funding
The groups have joined forces to urge Congress to fully fund the 2020 Census and the annual American Community Survey in its 2016 budget.
Codes and Standards | Mar 5, 2015
Charlotte, N.C., considers rule for gender-neutral public bathrooms
A few other cities, including Philadelphia, Austin, Texas, and Washington D.C., already have gender-neutral bathroom regulations.
Codes and Standards | Mar 5, 2015
FEMA cuts off funding to Indiana after Kokomo continues building stadium in flood zone
FEMA will withhold funding on $5.5 million worth of projects such as building tornado safe rooms in schools.
Codes and Standards | Mar 5, 2015
Construction problems at prison spur support to quash non-traditional project delivery in Iowa
Iowa lawmakers are investigating construction problems at the Fort Madison prison project and are scrutinizing rules regarding project delivery on state projects.
Codes and Standards | Mar 5, 2015
AEC industry groups look to harmonize green building standards, codes
The USGBC, ASHRAE, ICC, IES, and AIA are collaborating on a single green code.