Iris Communications, Inc. World Headquarters Design
	Index Design Foundation and Framing Insulation and Air Sealing Solar Energy Heating and Ventilation Interior Appliances and Lighting Recycled Materials Landscaping Certifications and Recognitions
	It was difficult to locate a solar-friendly lot, because urban lots are getting smaller all the time and new developments are not laid out with solar access in mind. Builder, Jim Chauncey of SunTerra Homes, found this cul-de-sac lot in a new development. The site is located about three miles from downtown and is near a bicycle corridor being developed by the parks district. Jim envisioned the north side of the building snuggling up to the hill for some earth sheltering. Another small hill to the south is covered with native Junipers and caused some adjustments to our solar glazing.
	The building footprint was placed as close as possible to the west property line to minimize shading from the Junipers. The site slopes gradually from west to east. Storm water is retained on site through a drainage channel and swale. There isn't much rain here (12 inches per year), but it can come in downpours or accumulate rapidly from snow melt.
	SunTerra proposed a split entry design with living spaces on the top floor (left). This allows the building to follow the slope, while pushing the south-facing glass up to rise above shading from nearby Juniper trees. The plan is small, only 1786 square feet. That includes about 250 square feet for business activities, such as publishing Oikos.com. The main living area and the office lie along the south wall. The centrally located entry and stairs collect and distribute solar heat throughout the home. The plumbing runs are short, because the bathrooms and kitchen are located near the center of the building. Virtually all of the plumbing occurs on interior walls, where it doesn't interfere with insulation.
	A key principle in the building design is combining insulation and air sealing in the same plane as the weather shell (roof, walls, slab-on-grade floors). This "functional integration" encloses a space that is fully usable from the ground level all the way to the peak of the roof. The roof is where this diverges most from typical construction. Sometimes called a "hot roof", it is illustrated in this drawing from the SunTerra Homes Conservation Guide. In a typical wood framed building, three functions (weather barrier, insulation and air sealing) often find themselves taking different paths through the building. A ventilated attic is a good example. Insulation is placed on the ceiling while attic vents encourage outside air to flow between the ceiling and the roof. This approach is known as a cold roof. The success of this particular hot roof relies on the layer of spray foam insulation applied directly to the underside of the roof sheathing. The closed-cell foam is impermeable to water vapor and is thick enough so that the surface temperture of the foam stays above the dew point even during the coldest periods. Water vapor that may enter the roof cavity is prevented from reaching the cold sheathing so it doesn't condense. As long as indoor water stays in its vapor form, it can't cause mold or decay.