The Lewis Creek Cottage is a net-zero-energy home designed by Rolf Kielman (AIA, Leed AP) for TruexCullins Architecture + Interior Design. It was designed for his daughter, her husband and their new baby boy. Kielman told me that the family was fully on board with net zero right from the start: “My son-in-law insisted that the house be conditioned without the use of carbon fuels.” Also, the orientation and placement of the house on the site was chosen for both passive and active (PV panels) solar gain. Situated on the northern edge of a hay meadow, with a view south to the Green Mountains, the house adjoins 65 acres of preserved land that is part of local efforts to improve the Lewis Creek Watershed. The primary living and gathering spaces are oriented toward the southern view and sun. Windows and glass doors provide ample natural light, beautiful views across the fields, and easy access to the outdoors. The white interior walls and natural wood floors impart a very modern feel.
The builder for this project was Jeremy O’Neil. According to architect Kielman, O’Neil has a long history of energy-efficient construction, and they have worked together before. Don Schroeder, another long-time colleague of Kielman, supplied and installed the solar array and did all the electrical wiring for the house. The 15kW solar array, with battery backup, provides auxiliary power when required. (Their utility, GMP, supports homeowner electrical backup grid load sharing (bit.do/gmp-home-nrg). This is an owner-installed Tesla storage system with two 13 kWh batteries.
A cold climate air-source heat pump system by Mitsubishi provides heating and cooling, as well as hot water. The windows are by Logic from Pinnacle Window Solutions of Maine (bit.do/logic-windows), good value Euro-type windows with an R value of 7. Air quality is controlled by a Lifebreath 205 Max HRV heat recovery system.
The efficient thermal envelope includes four inches of sub-slab insulation, R-42 walls and R-70 roof. The blower door test yielded a 0.5 ACH@50P. Other energy-saving features include low-flush toilets and Energy Star appliances. The exterior siding, cementitious Hardy Board, was chosen for ease of maintenance.
Rolf Kielman began his career designing solar-powered homes in the Philadelphia area during the energy crisis of the mid-seventies. He has been involved in environmentally conscious projects at VT Law School as well as South Farm Homes, a community of net-zero homes in Hinesburg, VT. He is a principal designer with TruexCullins Architecture + Interior Design of Burlington, VT. Learn about more of their high-performance projects at https://truexcullins.com.
Barbara Whitchurch is a freelance writer and a member of Passive House Vermont. She is the co-owner of a Passive House, a Nissan Leaf, a Kia Niro, and a St. Bernard.
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