Close-Up: Energy Upgrades
Part 1: Beardmore Building Shows How Deep Retrofits Can Bring Big Savings
Beardmore Building Shows How Deep Retrofits Can Bring Big Savings
By Ben Ikenson - June 2012 - Energy Efficiency
When the Beardmore Building came into the possession of Brian Runberg, the great-grandson of the building's original owner, its brilliance as a centerpiece for the small town of Priest River in the panhandle of northern Idaho had long faded. In its heyday, the two-story building housed offices, mercantile shops, a ballroom, and the Rex Theater, the 1922 site of a Hollywood movie premiere.
Its glamour gone the way of the region's mining and lumber boom, in 2006 Runberg, a Seattle architect, pursued an extensive historic restoration project that not only renewed the building's old charm but dramatically enhanced its energy performance.
"The building was certainly designed well for its day despite limited technology," says Runberg. "We recognized how it was intended to function and carefully implemented simple technology measures to augment those natural systems."
It's well known that certain investments such as increased insulation or occupancy sensors for lighting — both components of the Beardmore's update — can enhance energy performance while cutting utility bills, often paying for themselves and more. But, because so many building aspects operate as interrelated systems, integrated design strategies can maximize energy savings.
The "deep retrofit" of the 28,800-square-foot Beardmore Building resulted in an energy usage rate for its occupied portion of 32 kBtu/sf/yr. That's a considerable improvement over the energy usage prior to the restoration and one-third of the average office building in the United States, according to the most recent (2003) Commercial Building Energy Consumption Survey (CBECS).
"People often undervalue the inherent value of older buildings," says Ric Cochrane, project manager at Preservation Green Labs, a satellite of the National Trust for Historic Preservation, which recently released analyses of the environmental benefits associated with the reuse of buildings as opposed to demolition and new construction. "It shouldn't be assumed that they [older buildings] can't reach the same level of energy performance as new buildings."
Measuring Real Results
The Beardmore, which has been operating between six and eight cents per square foot per year, is no anomaly. With eight other buildings, it provides the basis for a study examining energy reduction associated with deep retrofits to offe analysis on building characteristics, efficiency measures, motivations, money, measured energy performance, market and tenant outcomes, and barriers and innovations. As part of efforts to accelerate commercial market adoption of deep, integrated energy efficiency solutions, the Northwest Energy Efficiency Alliance (NEEA) and New Buildings Institute (NBI), profiled the retrofits of the nine office buildings, looking closely at monitored energy usage.
The study, "A Search for Deep Energy Savings: NEEA's Study of Existing Building Energy Efficiency Renewals," was conducted "to identify successful design strategies and technologies applications for existing building retrofits and to verify their actual performance," says Mark Lyles, NBI project analyst.
For decades, the accepted industry practice has been to state building energy use based on its estimated performance, typically through modeling based on architectural and engineering plans.
"But we have evidence that there can be a wide variance in building performance compared to estimates, even for the most advanced buildings," says Lyles. "If the building industry is ever going to achieve the amount of deep energy savings required to drastically curb greenhouse gas emissions, building owners and operators must have access to data that tells them where their building falls short of expected or target performance and identifies areas of successful strategies."
Indeed, measuring results to provide such data was a major impetus for the case studies, which demonstrate how integrated design strategies applied to current new construction are also effective in existing buildings. All projects in the study are offices, including three designated "historic" buildings, with occupied floor space from 8,000 square feet to more than 390,000 square feet.
Each building was significantly retrofitted in the past 10 years and all accomplished drastically enhanced energy efficiency. More than half now save 50 percent more energy than the national average, and their average savings is 52 percent greater than the national average. Their average energy use intensity is 39 kBtu/square foot per year. Each received an Energy Star score in the top 20 percentile of their class. Energy Star scores are calculated by the program's Building Portfolio Manager benchmarking tool and have become the basis for many of the energy disclosure requirements in cities and states across the country.