New York Times Highlights Importance of Passive House Design
Share this post
This weekend the New York Times highlighted the growing effort of architects, builders, and homeowners to create houses that meet the strict German Passive House standard.
The article, Can We Build in a Brighter Shade of Green?, follows the story of one super efficient home built in Vermont.
It notes both the challenges both with designing such an efficient house, and getting the required skills and materials to construct it in America:
While some 25,000 certified passive structures — from schools and commercial buildings to homes and apartment houses — have already been built in Europe, there are just 13 in the United States, with a few dozen more in the pipeline.
“Even though the passive house standard is tried and true, and is used all throughout Europe — we know it works, we know there’s some simplicity to it,” says Mrs. Landau, “here in the United States, we were reinventing the wheel.”
… In Europe, this design-and-construction balancing act has an established manufacturing base to feed it; in the United States, not so much.
“If we were in Europe, most of the materials and equipment would be off-the-shelf and readily available from local suppliers,” says Tedd Benson, owner of Bensonwood Homes, a high-efficiency timber frame builder based in Walpole, N.H., that is constructing the Landau house. “And they would have already been vetted and certified by the Passivhaus Institut, with their performance specifications already linked into the passive-house software.
“Here, we have to invent the systems and try to find the materials, products and equipment that will help us meet the passive-house standards.”
Despite an initial price premium (for additional design time, thicker walls and insulation), over the course of its life a Passive House will return the initial investment many times over. The Landaus (featured in the Times article) expect to have the energy efficiency investments pay for themselves within 10 years.
Here’s a video the Times produced on the project:
In it, he cites design-focused (rather than energy-focused) architecture as one of the problems with building design, stating that “American architects are well schooled in matters of design, they often receive little training in the physics of how a structure breathes, how it consumes energy and how best to elevate its overall efficiency.”
While it is an accomplishment to see that “more than 1 million Energy Star qualified homes, which consume at least 15 percent less energy than conventional construction, have now been built in the United States,” Zeller goes on to say the “lack of [more] ambitious targets may actually be hindering the effort to address pressing problems like global warming.”
Why Code-Built is Not Efficient Enough
To understand why exceeding Energy Star ratings is desirable, Zeller includes a graphic of the HERS Index, a chart that shows the energy consumption of typical homes on a scale from zero to greater than 100, showing how different types of construction stack against each other.
Here’s the graphic, courtesy of Zero Energy Design:
We express the discussion in slightly different terms. Here’s a graphic from our renewable home heating page, where we frame the discussion of mechanical systems for heating a home in terms of btu/hrs required per square foot:
The underlying principle remains this: the more energy efficient a home is, the less heating load it requires. When minimal heating load is required, smaller, modest, and renewable heating options make sense, and monstrous fossil fuel heating systems are unneeded and uneconomical.
Going Passive in Maine
ReVision has worked on a number of high performance homes, here are links to a few:
- The GO Logic home in Belfast, Maine is the state’s first true passive house home. The prototype home has produced more energy than it has used to date and is a model for a new Belfast cohousing community.
- The home of architects Ian and Zofia Weiss uses many passive house principles. It uses radiant heat powered by solar hot water collectors with electric backup, and should eventually have grid-tied solar electric to make it near net-zero.
- The Bright Built Barn is a net-zero home in Rockland that incorporates leading-edge building practices and an innovative LED system to inform you as to whether the home is generating more energy than it is using.