Homeowners adding solar PV or thermal systems are often stymied when they discover that their homes' roof is not strong enough to support panels or faces the wrong way for optimal performance. Plus, every roof penetration is an invitation to spring a leak.
Massachusetts College of Art and Design and University of Massachusetts at Lowell joined forces to become Team Massachusetts. Team Massachusett's free-standing super structure, a houseport, as it were (the team called it a trellis), provides PV/thermal panel support, offset from the home structure and shading the home. This completely eliminates worries about weight or orientation or leaks. Done right, the structure also adds architectural interest to homes -- existing or new. As an operating bonus, adding air space under PV panels helps them run cooler and more efficiently.
The 945-square-foot 4D Home boldly asserts solar creds in contrast to Purdue's similarly-sized but deliberately understated INhome. Both two-bedroom homes are relatively affordable, 4D Home coming 4th in Affordability at estimated costs of $267,913.06. Similarly, the two homes were also close in Market Appeal with 4D fourth and Inhome fifth among the 19 contestants.
4D Home employs a combination of fiberglass and closed-cell polyurethane spray foam insulation to achieve R-56 walls, an R-57 floor and R-64 roof. The home is so tight that it achieves 0.6 air changes per hour (ACH) at 50 Pa. To maintain healthy air exchange, a heat recovery ventilator (HRV) brings in fresh air while recapturing as much as 85 percent of the exhausted air's thermal energy. Team Massachusetts was not one of the seven entrants to achieve net-zero status during competition. However, the team did take second place in the Energy Balance Category.
The 4D houseport structure also presents creative combinations of solar technologies. Hybrid-solar hot water collectors bootstrapped to the back of the PV panels capture the PV panels' excess heat. This double-solar heated water (collected in the solar hot water tank) provides 90 percent of the domestic hot water.
Inside, opening or closing two central partition walls easily reconfigures the home. Open the walls to create expansive space for family celebration. Close them up to create more intimate spaces. The two-bedrooms can be easily reconfigured to a one bedroom with a home office.
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