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Healthy homes for a healthy environment 
About the house Name: The Green Compact
Type: New, single family construction
Square Feet: 1,270
Location: Seattle’s Central District neighborhood
Completed: January 2005
This open, airy house on a small city infill lot is packed with features that conserve resources and add pizzazz. These include a vegetated roof and rain barrels to keep stress off the city’s storm drains, a single tankless water heater to heat the house and supply the taps, and a heat-recovery ventilator to bring in fresh air and warm it with heatfrom stale air flowing out.
To cut down on materials that went into the house, the two-bedroom, 1 3/4-bath house was designed to fit within 1,270 square feet. The builders used salvaged materials wherever they could. Some are hidden away in the walls, where about 90 percent of the framing lumber is in its second life, but others are showpieces: a vintage stairway balustrade, reclaimed doors and a striking trough sink that came from a school art room. In addition, structural materials double as finished surfaces in many cases. The building’s concrete slab, for example, is also the finished floor for the ground level, while plywood subfloors on the second floor and in the loft got a clear finish and are now the finished flooring.
GreenLeaf Construction, which builds seven to 10 spec homes a year, had incorporated “green” features in earlier projects, but never on the scale one here. The company wanted to get its houses and building practices to the next level and decided to do that by building this house to qualify for Built Green™ 4-Star certification. The house met that goal. GreenLeaf has since incorporated many of the strategies as its standard way of doing business. And the house sold quickly for a premium price, more than making up for the 10-15 percent in added costs.
Goals/Challenges
The right team
The first challenge, according to GreenLeaf President Jim Barger, was to find an architect who could not only come up with a suitable design for the 3,402-square-foot lot but work with the builders as part of a team and help them learn.
David Vandervort Architects took the lead in designing the site and floor plans, and the builders took the lead in finding finish materials. When they wanted to try something new, such as using wheat board panels instead of hardboard in the kitchen, the architect would say, “Great idea; do it,” or counsel against it based on technical knowledge.
Salvaged materials
Due to the high price of sustainably harvested lumber, the project team switched to reclaimed lumber. GreenLeaf crews partially deconstructed two houses by hand, and they put out word that they would gladly pick up leftovers from other jobs. The added labor costs balanced out with what the company saved. To persuade the building inspector to allow use of wood without a grade stamp, GreenLeaf separated sound wood from pieces with rot or insect damage. The inspector, seeing that the crew was careful, went along but reserved the right to call in a grading inspector if he saw problematic lumber being used.
Tracking down other salvaged materials became sort of a hobby — fun, even if not always strictly cost-effective because of the time it took. At Seattle stores that specialize in selling used building materials, GreenLeaf found a 1970s butcher block to use as a kitchen counter, old school bleacher seats to cut into stair treads, an old ship’s ladder to provide access to a loft, and many other items. The company also salvaged and recycled its own leftover materials through King County’s Construction Works program.
Site issues
As with many infill properties, this lot was narrow and small, and it had existing homes on both sides. The architect and builder focused on finding a plan that would respect the neighboring houses and not make them darker, and yet give the new house good light and air circulation. Locating the house near the rear of the lot, where there is good southern exposure, solved this problem. The eventual buyers love the arrangement, which they say gives the house a secret-garden feel. The neighbors, too, are grateful.
Green roof
Vegetation covers about 20 percent of the roof area, creating a roof area that’s accessible from the loft. Metal roofing on the rest of the structure drains partly into the roof garden and partly into two rain barrels. Overflow goes into an infiltration trench landscaped with plants that thrive where the soil is soggy periodically. This puts all rainwater to good use and keeps it out
of storm drains.
Hot water
A single tankless water heater supplies taps and two radiantheat systems for the house. On the ground floor, hot water circulates in pipes embedded in the concrete slab, which is insulated underneath. Upstairs, hot water flows through wall radiators. Because there are no ducts, the heating system doesn’t blow dusty air through the house. Tankless water heaters cost more than conventional water heaters up front, but save money over time as they save energy. Making the
water-heater double as the furnace more than compensated for that.
Energy efficiency
This house should leak 12 percent less heat than houses that merely meet the state energy code. Advanced framing and added insulation bolster places that are weak links in many houses, such as headers, corners and intersections that involve interior and exterior walls. Windows are oriented to bring in free heat from the sun, and south-facing overhangs provide shading when needed. The cooling system consists of ceiling fans and cross ventilation. Appliances are Energy Star rated.
Lessons learned Know what it means to innovate
Using one piece of equipment to supply both the hot tap water and two radiant-heat systems turned out to be trickier than the builders expected. The systems eventually were brought into balance, but only after considerable tinkering. Barger says the lesson from this is not to get bogged down in trying too many innovative features at once. There will always be a learning curve — you just can’t face too many.
Think like a buyer
About half the potential buyers were drawn to the house by its beauty: the way Vandervort set the house on the lot and the architectural features he incorporated; the builder’s craftsmanship; even the color scheme, which came from a consultant that GreenLeaf hired. These potential buyers also loved the structural materials used as finished surfaces, although the green reasons for choosing this approach weren’t their primary motivator. However, when GreenLeaf built the same basic house a short time later, that buyer considered green features to be crucial. In this evolving market, green features are clearly important, but so are pop and sizzle.
Source: City of Seattle Department of Planning and Development
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