A Year in a High-Performance Home

Reader Contribution by Sarah Lozanova

In a leap of faith, a year ago my family joined Belfast Cohousing & Ecovillage in Midcoast Maine, a 36-unit multigenerational community on 42 acres. My husband and I loaded all our possessions into a truck and uprooted our two young children as we moved from Wisconsin to a quaint coastal community. Upon our arrival, we were greeted by friendly neighbors who helped us unload and unpack. Our children began exploring the property and we all began building friendships within our community. We instantly enjoyed living in our new high-performance home because sunlight fills our living space, fresh air circulates throughout the home and our utility bills are very low.

All Belfast Ecovillage homes are built to the passive house standard (although not certified), so we use 90 percent less energy for heating and cooling than the typical code-built home. The solar orientation and huge triple-pane windows and doors allow the sun to passively heat our home. The cement slab absorbs heat during the day and releases it at night when the temperature drops, helping to maintain more even temperatures. Generous amounts of insulation and virtually airtight construction allow the heating system to remain idle much of the time. Our heat recovery ventilation (HRV) system constantly supplies a stream of fresh air to the bedrooms, while removing stale air from the kitchen and bathroom.

Fresh Indoor Air

Most conventional homes leak lots of air out of the home, thus losing heat and creating drafts in the winter. Because homes built to the passive house standard are virtually airtight, they would have air-quality issues if there wasn’t mechanical ventilation. Exhaust fans are not energy-efficient in cold climates because they vent heated air out of the home without capturing the heat, so our home doesn’t have an exhaust fan in the bathroom or a range hood in the kitchen.

Instead, we have a Zehnder HRV system, which constantly brings fresh, tempered outdoor air into the bedrooms and removes stale air from the kitchen and bathroom. These systems are up to 95 percent efficient in capturing heat from the exhaust air before it leaves the home and transferring it to the incoming air, so we can have both fresh air and energy efficiency, even on the coldest days of the year.

Energy Efficiency

Despite the cold Maine climate, we haven’t needed to use our heating system until late October or early November. On sunny days in winter, our home can heat up 10 degrees or more solely from the sun, with the heating system turned off. Even on winter nights, our heating system turns on sparingly because of generous amounts of insulation in the walls, ceiling and slab; an energy-efficient standing-seam roof; and triple-pane windows and doors.

Our highest electric bill for heat, hot water, cooking and plug loads was during January, for a grand total of $120, at roughly $0.15 per kilowatt hour. I know people who spent more than $1,000 a month on heat alone for a similar-sized older home in our area. We later learned the difference that removing screens from southern windows makes in boosting the heating effect of the sun, further reducing winter heat bills. The upfront cost of the home was greater because of the energy-efficient features, which have an estimated 7.5-year payback period.


Even on the coldest winter nights, our home is draft-free, and it’s comfortable to sit by the windows. Our home is heated largely by the sun, which delivers gradual heat. The HRV system helps circulate the heat from the sun in the home, balancing the temperatures between the rooms on the south side (which receives more sun) and the north side of the home. Our last home had a forced-air furnace, and I really appreciate not having dry hot air blowing on me during the heating season.

In the summer, our home remained very comfortable, even with so many south-facing windows. The Unilux windows and one of the doors can tilt in using one hinge at the bottom to allow them to open at the top, providing lots of ventilation. When it’s hotter outside than inside, the HRV system can actually pre-cool the incoming air from the outgoing air.

No Moisture Issues

I’ve lived in several homes that developed mold above the shower, despite diligentuse of an exhaust fan. Even bath towels would get moldy when left on a hook to dry during humid weather. This has not been an issue in our new high-performance house. We chose to forgo having a clothes dryer and even on humid, rainy days we can air-dry laundry inside without mold.

Healthier Living

Although we are mindful of using nontoxic products in our home, it can be difficult to avoid them completely. Having an HRV system constantly supply fresh air to the home helps mitigate the buildup of toxins in the indoor air. In recent years, I’ve found myself developing chemical sensitivities to synthetic fragrances. If I mistakenly light a scented candle or my daughter comes home wearing synthetic perfume, I can boost the speed of the HRV system to increase the amount of fresh air brought into the home to reduce my reaction.

One of our neighbors was experiencing a chemical sensitivity after she had flooring installed in her home. Instead of having to open windows during cool fall weather, she was able to boost the HRV system, which eliminated her symptoms. The HRV system also filters out pollen and dust, a great feature for people who suffer from allergies.

Energy Independence

Over the summer, 11 solar systems were installed at Belfast Ecovillage through a community purchase initiative with Capital City Renewables. By purchasing and installing the systems collectively, members received wholesale rates for solar panels and components. Now 22 of the homes are near net-zero, producing all or most of the power used over the course of the year.

There is an excitement in the neighborhood around energy conservation and green power, which began with the planning of the high-performance houses and expanded with the installation of the solar systems. Our high-performance home and community living are helping us to live our dream of green living.

Sarah Lozanova is an environmental and health journalist with an MBA in sustainable management. She lives in a net-zero house in Belfast Cohousing & Ecovillage in midcoast Maine with her husband and two children.

Need Help? Call 1-800-234-3368