Green House in Georgia
Oversized doors in the master bedroom and operable windows allow afternoon breezes to circulate through the house. It was remarkable to note, one day in early July 2009, that the house was still cool while the doors stood open, even in the subtropical summer.
Heat gain is reduced by glazing with a low solar heat gain coefficient (0.36 SHGC) and by recyclable solar roller shades at all exposed glazing. Energy-recovery ventilation and LED lighting help further reduce the home's energy use.
A covered deck and a screened porch add a substantial amount of outdoor living space. The smaller screened porch faces the street and is positioned to capture breezes from two or three directions, while the deck off the master bedroom is open, shaded by the house's broad eaves.
Inverted by Design
Robert Cain says he took care inserting the RainShine House into a neighborhood dominated by dollhouse-like homes dating from the 1920s to the '50s. "The exterior design is modulated pretty carefully to give the same rhythm and feel that the older houses in the neighborhood have," he says.
The architect reports that the most misunderstood feature of the house is likely its soaring butterfly roof. A native Southerner from northern Alabama, Cain points out that even though an inverted-gable roof may be atypical in the region now, it is not strictly novel. "My grandfather had a shed roof on his barn that sloped like that," Cain recalls. "It wasn't strictly a butterfly; it was two roofs of intersecting sheds at different levels. He used it to collect rain in barrels."
The RainShine roof design arose for the same purpose. "In this case," says Cain, "the decision to use the butterfly roof was directly related to 'How do you to easily collect water and use it for a rain harvest system?'" The roof feeds rain to five 500-gallon (1,900-liter) cisterns installed in the basement, where the water is stored for use in toilets.
The roof is also oriented to maximize southern exposure for photovoltaic panels. While the PV panels don't power the house, the energy they generate is sold back to the local power company's grid in exchange for green power credit.
Hunt for Materials
Cain, who says he's been building green since the 1970s, reports that finding sustainable materials was one of his biggest challenges for the RainShine House. "I think the Southeast is not the leading area of the country to find local sustainable products," he says. "We had to dig to find stuff. You're seeing more and more everyday now in our region. But when we started this a while ago, it was difficult to find locally."
Heart-pine floors and stairs are the most visible reclaimed element; they make a huge difference in the warmth and feel of the house. The wood was salvaged from the early-1800s Atlanta stables, which had recently been torn down. The clients and architect saw the lumber in beams, before it was sawn, and elected to use it throughout the house. This became one of their best aesthetic decisions — the wood simply glows. Surprise housewarming gifts for the clients were coffee and console tables made from the same lumber.
RainShine also includes a variety of recycled-content materials, such as fiber cement siding and concrete-and-glass kitchen countertops. The steel that supports the roof is 100 percent recycled material from local sources, and the porches are made of Trex decking, a composite of recycled and reclaimed wood and plastic. Fixed rugs are made of modular carpet tiles, a recycled product from FLOR, whose parent company, Atlanta-based Interface, doesn't just encourage recycling of its product — it actually pays customers to ship it back when they're done with it.
The RainShine House is on a tight one-third-acre (0.13-hectare) lot, bounded on one side by a creek and a storm culvert. The low-maintenance landscape designed by Lynn Saussy includes native, drought-tolerant shrubs and grasses, and deciduous trees placed strategically to shade the house in summer without blocking the solar panels.
There is no lawn, and the house's lack of a garage by is by design — the owners are cyclists who also rely on walking and using Atlanta's MARTA mass transit. According to Cain, the rain gardens and rainwater harvesting systems installed on site confer permeability equivalent to that of a woodland.
Aside from reactions to the inverted-gable roof, the questions the clients heard most often about their building project were: Why tear down an existing house? And what's the deal with hiding construction under a large blue tarp?
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