There are historic buildings all around us. There are some that have special significance and get special treatment. Most, however, didn’t play a dramatic role in history and still are working buildings. They just have been standing for a long time.
These structures aren’t necessarily inefficient, but generally have a different profile than more modern buildings because they were built in a different era. They are getting the special attention they need from ASHRAE. This week, the organization announced that Guideline 34P, which is “Energy Guideline for Historical Buildings” will be open for a second comment period until May 2.
The guideline was developed by the 34P committee. Committee member William Rose said that the approach to improving energy efficiency in historic buildings must be a bit different because the proactive cooperation of a significant group not present in other upgrade scenarios – preservationists – must be courted.
Where possible, the building should be left as it is. "There’s a predisposition to do nothing, leave it along,” he said. “If the building is already energy efficient and isn’t a burden on society, generally that’s fine.”
That often is the case. In many cases, older generations of buildings have a higher native level of energy efficiency. That’s because the ones that survive generally were solidly built and have been well cared for over the years, Rose said. And, though the building may be old, internal structures and systems generally have been updated over time. People like old buildings and take care of them. “When parts get replaced they get replaced with good parts,” Rose said. “So old buildings have a lot of energy benefits already. People don’t credit that. They really should.”
A big change has hit the world of energy efficiency and historic buildings. The International Energy Conservation Code (IECC) formerly gave these structures blanket exemptions from energy codes. That practice ended last year. Now, Rose said, a case must be made to the IECC to win the exemption.
This has a significant impact on the entire historic building industry segment. Rose said that a new relationship must be created between people whose primary interest is in energy efficiency and the preservationists who suddenly have to think more deeply about the subject.
ASHRAE’s guidelines can play an important role in forging the bond between the energy efficiency side and preservationists, Rose said. Though preservationists are interested in saving money and acting in an environmentally responsible way, they can be protective and reluctant to make the changes necessary. ASHRAE, Rose said, “does a bit of hand holding” and worked to break down silos and get the energy efficiency side (including mechanical engineers and building designers) and preservationists to communicate more effectively. It is, in short, the organization – through the guidelines -- is well positioned to foster cooperation.
Some changes will be necessary. An example Rose gave was that older buildings tend to lack insulation and compensate by using a lot of energy in the form of heating. That must stop. However, old masonry “likes” heat. “We are going to save energy and you will not be able to throw heat at the masonry as you used to,” Rose said. “It will be colder than before and by virtue of being colder it is going to be wetter than it was before. A lot of preservationists would say, ‘Stop right there. No, no. We are done.’ One thing that the guidelines says, ‘No, we are going to keep talking even if gets wetter than before, we still have job to do.’ ”
