“My wife and I recently fulfilled our goal of building a planet-friendly home for our golden years. Sustainable energy consumption and aging in place were our “must-haves.” Low environmental impact materials, good water management, and wildlife-friendly landscaping were additional goals. We also wanted the home to serve as an inspiration—a demonstration of sustainable construction and low-impact landscaping.
We had our home designed to meet the rigorous standards of The Passive House Institute. The end result is a home that is certified as Passive House Plus—only the second home to achieve this certification in the U.S. The primary energy source for the home is our rooftop solar array. During the summer, we expect to sell as much excess production to our electric utility as we buy during the shorter days of winter.
The house is super-insulated with 18-inch thick walls and is extremely airtight to prevent unwanted heat loss or gain. A heat and humidity recovery ventilation system provides indoor air quality. Heating and cooling are provided by an air source heat pump.
An on-demand plumbing loop brings hot water to faucets and returns standing cold water to the water heater, eliminating the need to run cold water down the drain until hot water arrives. Heat captured from waste water helps preheat cold water entering the water heater. All water supply lines—hot and cold—are insulated to preserve water temperature and control condensation. We wanted ample natural light throughout the house. Large windows on the south also provide heat gain in winter via captured sunlight. Adjustable exterior sun blinds block heat gain when it’s not wanted. All windows and exterior doors are triple glazed and have insulation barriers in the frames to minimize heat transfer. The magenta trim was a visual offset to the green siding—choosing “lively” over “boring.” The design team initially thought the color choices might be too bold. But, ultimately, the “spring cherry trees in bloom” theme turned out to be a perfect fit for the home.
warmth, and future house plants.
To reduce bird window collisions, our largest windows feature bird safe glass with an imprinted mesh pattern, visible only at ultraviolet wavelengths. Humans can’t see this imprint, but birds see it and avoid it.
The framing and sheathing are a mix of sustainably produced lumber, certified by the Forest Stewardship Council or the Sustainable Forest Initiative. Our home’s foundations incorporate a high percentage of fly ash instead of pure concrete in order to reduce the embodied carbon cost of conventional concrete. The siding is a combination of steel, a long-life material that can be fully recycled at the end of its life span, and heat-treated ash from trees killed by the Emerald Ash Borer. Flooring is a mix of ceramic tile, and cork and linoleum made from renewable materials. Wall and roof insulation is dense-pack cellulose made from recycled newspaper.
Rain gardens capture all of the runoff from the house and garage roofs, the driveway, and a substantial portion of the lot. A grant from our local watershed district—the Capitol Region Watershed District—offset a portion of the construction and planting cost. We used native species selected for pollen and nectar production for locally native insects.
To accommodate aging in place, all entries are at grade level. Rooms and hallways are sized for ease of use with wheelchairs. The master bath has a roll-in shower. All faucet handles, door and cabinet handles, and light switches are ADA compliant. An elevator supplements the stairway and is currently used when we have guests with disabilities.
We’re still in our first year of occupancy. The appreciation we have for the home’s energy performance, design efficiency, and comfort is already rewarding, and we expect further experience to continue to raise our satisfaction.
We hope to offer tours when that becomes practical again. For further details, please visit the designer’s web page as well as a comprehensive visual review of the project.”
permeable driveway.
About the Author. Dave Crawford has dreamt of having a home designed for energy sustainability for most of his life. He’s also landscaped with native plants at his various homes since the 1980s. Recently retired from a career as an environmental educator and landscape restorationist with the Minnesota Department of Natural Resources, he continues to live out his dreams with his wife and share them with those who are interested. Readers can follow his ongoing efforts and wildlife observations on his Facebook page.