Ask the Architect

Producing more energy than we use

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Q. I’m interested in redoing my home to be a zero-energy user. I’ve been investigating the latest materials, like foam insulation and recycled flooring, bamboo (natural) and even low no-emission paint. What can you tell me about what to use and who can build it the way I want it? You always write about builders not cooperating, and I did a lot of homework already and don’t want to be disappointed. It’s a lot of money to spend.

A. It’s great to aspire to “net-zero-energy” architecture, where the home produces more energy than it uses. It’s also difficult to achieve without the right team of people, especially if you’ve done so much studying and collecting of ideas and materials. Start with the basics, like a good designer who knows what you’re talking about and can sit with you, shaping your concepts, in a holistic process, and a team of installers near the beginning of that process who can work as a team. That means taking every piece of the jigsaw puzzle and making sure it integrates well. This results in not getting a competitive bid, but getting what you need.

You must integrate whole systems. For example, bamboo floor is anti-static, anti-microbial, resists expansion and contraction, and can be well integrated with clean, radiant, under-floor heat to avoid exposed baseboard fins that gather dust and are less efficient. Geothermal and solar hot water enhance the system, all at great upfront cost. Round out the system with high-density insulation (closed cell and foamed in place) and you have one part of the puzzle solved. Where this starts to fall apart is when, for example, the foam insulation is open cell, but they don’t tell you until it’s in, and the installer does a poor job of making sure the entire wall cavity is filled completely, with no gaps, holes or pockets.

I recently inspected a project where we selected fiberglass batt r-15 insulation. The contractor recommended a switch to foam, which was a great if not more expensive idea (exceeding the original budget). After a building inspector saw it and called me, I looked and saw gaps, holes and pockets 5 feet long and 1 inch deep in an 8-foot-tall space in almost every 14½-inch-wide wall cavity throughout the construction. Even though the installer said the foam was still better, a quick calculation of the r-value showed that unless the cavity was completely filled, the foam was only r-7 to r-9 where the code requires r-11 minimum, not to mention how cold the room will actually be and how much heat will be lost. The fiberglass batt insulation turned out to be a better product, in this case, because the r-value would be higher and there is much more ability to run electric wiring without cutting out insulation. Unlike standard work, you require much more cooperation, a contractor/team leader and the right design.

© 2016 Monte Leeper. Readers are encouraged to send questions to yourhousedr@aol.com, with “Herald question” in the subject line, or to Herald Homes, 2 Endo Blvd., Garden City, NY 11530, Attn: Monte Leeper, architect.