The Adirondack-style, shingled home, complete with a pond and running stream, holds its own along the estate-studded back roads of New Canaan, Connecticut. But if you slow down long enough to give this custom-built property more than a cursory admiring glance, you will notice what one local clean energy advocate recently called “an encyclopedia of green ideas.”
In fact, that’s what the owners want you to do: stop, look, and learn. Etta Kantor, who converted her VW Jetta to bio-diesel vegetable oil fuel a half-decade ago, along with her husband, Nate, had very specific environmental and educational objectives in mind when they enlisted architect Jim Edgcomb, builders Mike and Chris Trolle, green building consultants Steven Winter Associates, and what became a fairly large team of subcontractors to realize their vision.
“The couple’s goals were to build the greenest, most energy efficient house possible,” recalls Edgcomb. “Finding the land took a while, because good parcels are not so plentiful in the fairly well developed area where they wanted to build. This site had attributes they were looking for, including natural water features and open areas in the right places to incorporate photovoltaics in the program. It balanced beautiful views and the necessary southern exposure.”
At the same time, the house plan that gradually emerged had a complex and detailed shape. The homeowners also had a long list of materials and systems that they wanted to include in the program.
“An indispensable part of our process is to first make the box as airtight as possible,” says Chris Trolle, the project’s engineer, who did the math for the home’s performance features.
The super-insulating process was extensive. Basement walls are precast concrete, insulated with both rigid foam board (1”) and spray foam. The floor slab sits on a 6” bed of crushed stone, to keep it dry, and 2” of XPS foam board. Above grade walls were framed with 2x6, 24” OC. Roofing was framed with 2x12, also 24” OC. In addition, horizontal 2x3 strapping over studs and beneath the finish drywalls in the basement, above grade, and on interior roof rafters provided a generous increase to the cavity space for spray foam insulation, which in turn yielded significant increases in R-value (R-58 roof, R-31 above grade, R-39 basement).
Also part of the basics were the windows; most are triple-glazed casements with two layers of low-E coatings and two 1/2” air spaces filled with argon; these features contribute to a U-value of .21, and an R-5 rating. Frames are solid wood and aluminum clad so that they are virtually maintenance free.
Because the clients wanted the visual aesthetic of stained-shingle cladding, they selected FSC-certified cedar from local sources. To increase the durability of this material, the builders installed a special mesh fabric between the building wrap and shingles, allowing moisture to drain out and away.
For the roof sheathing, the clients chose a shingle manufactured from recycled rubber. The shingles, which even close-up look like slate, met the client’s expectations for sustainability; cost-wise, the roof is comparable in price and durability to a standing seam metal product.
“Our focus is always on the building envelope, first,” says Edgcomb. “Once you have a durable, high performance envelope, you can add the systems.”
To provide about 94% of the home’s electricity, a 10.8 kW system, consisting of 1,000 square feet of pole-mounted PV panels, was installed in the optimum location on the nearly five-acre property. But it is the hot water system, which supplies radiant floor heating, domestic hot water, and heated pool water in the warm weather months, that uses the most ingenious integration of three high-efficiency sources.
500 square feet of solar thermal panels on the roof heat a custom-made1,000-gallon water tank, which is used like a battery to store heat for all the home’s requirements. When the sun isn’t producing enough heat, a pellet boiler with automatic feed backs up the solar panels. In the event that these systems cannot keep up with demand, a super high-efficiency (AFUE 95) propane boiler will kick in.
Wherever possible, the clients wanted local and sustainable materials used throughout the interior and exterior. Stone for building facings and landscape stonework was harvested on or near the property; reclaimed lumber and FSC-certified wood products from Northeast sources were also used for the structure and finish items such as the kitchen island and desk tops. Countertops made from recycled glass at a Brooklyn, N.Y., fabricator were yet another local selection.
“They were incredible clients,” acknowledges Edgcomb, and the Trolles agree. “They were completely committed to doing the right thing.”
The owners have taken the “reduce, reuse, recycle” mantra to the farthest degree possible, with a graywater system—the first domestic system approved by the state—that takes water drained from sinks, showers and the washing machine and uses it to flush toilets.
In addition, the couple had a composting toilet (which looks like every other water closet) installed in the master bath, linked to a composter in the basement that will harvest waste and turn it into fertilizer—a factoid which leads us to the outdoors.
The story of this home’s green logic would not be complete without the efforts made to create a natural, native, and productive landscape. A thoroughly planned and meticulously installed design complements the home’s resource-conserving features. Rainwater runoff from the roof is captured in underground cisterns, which in turn is used for irrigation. To insure that no rainwater runs away, careful grading and installation of a stone-lined bio-swale, planted with water loving plants that absorb the moisture, runs into a rain garden that will grow more luxuriant with each passing season.
For other plantings, the clients chose fruit trees and many edible herbs and berries for the garden. Fields continually transform themselves with a succession of native flowering plants. A fenced vegetable garden will provide produce for the family, with excess harvest donated to local food banks.
Even though the pool was one feature that the couple could not bear to leave off the building program, the previously mentioned heating system and an automatic pool cover to conserve heated water makes even this indulgence more sustainable.
The resulting home and property is a living green laboratory—it has earned LEED platinum and NGBS Emerald status—that the clients enjoy sharing with school and university groups, other building professionals and green advocacy groups, and their neighbors.