Dominick Tringali Architects (DTA) in Bloomfield Hills, Mich., is raising the bar for Habitat for Humanity homes built in the Detroit area with a model designed to achieve LEED-Platinum and Green Built Michigan certifications. The first unit in Pontiac was completed in November.
“Our goal was to create a sustainable prototype home for Habitat for Humanity that meets LEED requirements and raises the benchmark for future affordable housing,” says Steve McKay, lead designer for DTA on the project. “We’ve incorporated sustainable building practices that will reduce construction costs, reduce energy operating costs, and create a healthy living environment for the occupants.”
Habitat used this first unit for training and will eventually adopt the same green specs for all of its homes in the area.
The 1,768-square-foot, five-bedroom, two-bath model was designed to house a multigenerational family on two floors. It includes siting, energy, resource, and health-related features that combine with the affordable cost considerations to meet DTA’s goals, as well as the high performance requirements.
The exterior elevations of the home were designed with deeper roof overhangs determined by using solar calculations to both maximize and minimize the sun exposure based on the time of year. In addition, authentic window canopies further shade the South-facing windows and protect the wall and window openings from water intrusion.
Features that contribute to the affordable construction include a sealed and insulated crawl space; value-engineered framing, including single top plates and reduced-lumber corners, headers, and window-opening assemblies; and engineered roof trusses.
Energy performance goals are attained through an enhanced and air-tightened shell, including R-10 Dow Styrofoam–insulated foundation walls and crawl space floor; caulked seams, joints, and shell penetrations; R-25 walls with Nu-Wool cellulose cavity insulation and 1-inch-thick exterior R-5 Dow foam sheathing; Nu-Wool attic insulation; Simonton Energy Star–rated, low-E windows with argon gas fill; and a high-efficiency, sealed-combustion furnace rated at 90%-plus AFUE designed for short duct runs (all ducts installed in conditioned space).
The HVAC system includes make-up air features in response to the reduced air leakage, and all caulks, adhesives, and finishes used in the house are either low- or zero-VOC to meet indoor air quality provisions.
The first home was built by Brooklyn Homes, an area green builder, with supervised sweat-equity labor contributed by the owner-family. All LEED and Green Built Michigan construction and performance requirements were site-verified by Nelson Energy Seal, a HERS- and USGBC-approved green rater. And, as part of the overall mission, jobsite waste was minimized as much as possible and sorted for recycling throughout construction.
Dominick Tringali Architects has developed the DTA Green Guide CD, a collection of green building construction details and suggested specifications available for $199. Contact DTA at 248.335.8888 or www.dtarchitects.com.