At the NESEA Building Energy 10 Conference in Boston, great minds have been busy discussing the best ways to build (and rebuild) better buildings. And talks range from covering mechanical details to virtual collaboration in design. Still, one recurrent theme has dominated the conference. "Net zero" was the buzz word a couple of years ago, says Passive House guru Jamie Wolf of WolfWorks. "Now, it's 'deep energy retrofit.' " As much as the concept is gaining broader recognition, there are varying definitions about what it means.
So, we figured we'd ask attendees and experts: just what is a Deep Energy Retrofit?
Jamie Wolf: "We're aiming to reach a threshold of energy use. We say 70 to 90 percent energy reduction of a bad building. It's dramatic. That's why we use the word 'deep.' Anybody who is going to embrace what it takes do a deep energy retrofit has got to be thinking way beyond personal benefit. At the end of the day, we wouldn't be here if we hadn't stared carbon in the face. We looked at our buildings and said, 'we'd better get a move on.' "
Cador Pricejones, project manager with Byggmeister, Inc., and owner of a (nearly finished) deep energy retrofit in Somerville, MA: "A lot of people define it as a 75 percent reduction in energy. But I don't think it's too helpful to get hung up on the numbers. Whatever you can do is a help, a long as you take a whole-house approach. You can phase it, or do it all at once. Just do as much as you possibly can to the entire house."
Ken Neuhauser, Building Sciences Corporation: "Deep energy retrofits are hard. They are not simple, quick or cheap. I would define them as taking an existing building and reducing its energy use by 50 percent over a new construction, code-built building. If we said 50 percent reduction over the current energy use, that would be easy. But if it's a dog, and you reduce it 50 percent, it's still a dog. We can do better than that."
John Livermore, Livermore Energy Associates: "I would define a deep energy retrofit as … a project that involves super-insulating the building shell, and achieves over 50 percent energy savings."
Sean Jeffords, Beyond Green Construction: "A deep energy reduction is.. a comprehensive renovation or remodeling strategy that when done properly will substantially improve the comfort, durability, health and air quality of a home or building. These efforts should provide a minimum energy use reduction of 50% or greater to receive DER status."
Linda Wigington, founder of ACI and the 1000 Home Challenge: "Retrofits are what people do when they thicken the walls. We're talking total energy reduction. You're not going to get the 75 to 90 percent energy reduction we're aiming for in the 1000 Home Challenge with retrofits. You're going to reduce heating use—and you could reach 75 percent less—but you're not going to affect other energy use. To get really deep energy reductions, we need to look at how we live in our houses. How we live in them matters a lot."
What do you think? And....as Ken says, percent of what?