Green, Greener, Greenest

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Inside this Article

Active and passive solar
Active and passive solar pair up to offset this home’s energy needs.
House’s narrow footprint
The house’s narrow footprint makes the best use of the small lot.
South-facing windows
Well-placed windows on a south wall let in sunlight for warmth. Honeycombed shades slow heat loss through the windows at night.
Energy Star appliances
Energy Star appliances are part of the whole-house approach to efficiency.
Custom-cut structural insulated panels
Custom-cut structural insulated panels go up fast, and insulate well with little air leakage or thermal bridging.
SIP wall provides room for additional insulation
A nonloadbearing 2-by-4 wall inside the SIP wall provides room for additional insulation.
SIP roof is placed by crane
The 12-inch-thick SIP roof is placed by crane.
Efficient washer and dryer
An efficient washer and dryer help save water and energy.
Drying rack
Linda and Brad routinely use the drying rack for even greater energy savings.
Space-saving fold-down desks
Space-saving is part of energy savings. Linda and Brad have matching fold-down desks in one bedroom, which also functions as an office.
T8 fixtures
LEDs are used throughout the house, including in these T8 fixtures in the utility spaces.
Thermal blinds
Even the most efficient windows lose heat. Thermal blinds help keep it in.
A minisplit heat pump
A minisplit heat pump that helps heat and cool the home with minimal energy input. (Outdoor part shown).
A minisplit heat pump
A minisplit heat pump that helps heat and cool the home with minimal energy input. (Indoor part shown)
Wall-mounted minisplit air handler
The wall-mounted minisplit air handler in the guest bedroom is unobtrusive.
Aurora solar thermal collectors
Two 4- by 8-foot Aurora solar thermal collectors provide as much as 85% of the homeowners’ hot water needs.
Solar hot water components
Peeking up into the thermal closet at the expansion tank, drainback tank, and Grundfos circulator pump.
A single-tank drainback system
A single-tank drainback system is ideal for small spaces. This utility closet was sized specifically for the system.
PV array
Part of the 12 kW PV array.
PV AC disconnect
At ground level, the PV AC disconnect is the only evidence of the system.
utility kWh meter
The well-labeled utility kWh meter.
Low-flow fixture
Water conservation is a key design element: Low-flow fixtures reduce usage. A greywater system distributes the used water in the landscape.
Underground 11,000-gallon rainwater cistern
Perforated black poly pipe is the inner supporting structure for an underground 11,000-gallon rainwater cistern.
Gutters feed directly into the cistern
Gutters feed directly into the cistern.
The garden sits above the rainwater storage tank
The garden is planted in topsoil that sits above the rainwater storage tank.
Linda and Brad
Linda and Brad cozy up in their high-performance home.
Active and passive solar
House’s narrow footprint
South-facing windows
Energy Star appliances
Custom-cut structural insulated panels
SIP wall provides room for additional insulation
SIP roof is placed by crane
Efficient washer and dryer
Drying rack
Space-saving fold-down desks
T8 fixtures
Thermal blinds
A minisplit heat pump
A minisplit heat pump
Wall-mounted minisplit air handler
Aurora solar thermal collectors
Solar hot water components
A single-tank drainback system
PV array
PV AC disconnect
utility kWh meter
Low-flow fixture
Underground 11,000-gallon rainwater cistern
Gutters feed directly into the cistern
The garden sits above the rainwater storage tank
Linda and Brad

Building “green” means lots of different things for homeowners as well as homebuilders. This isn’t surprising considering the array of green building certification programs in the United States today, such as Energy Star, LEED, ICC-700 National Green Building Standard, Earth Advantage, and Passive House (see “Green Home Certifications” sidebar).

Despite the differences, the most important element of any green building strategy is maximizing energy efficiency. And the biggest impact you can have on energy use is by building smaller. According to the Oregon Department of Environmental Quality, in the 70-year life of a U.S. home, the largest use of energy is in occupancy use—not the embodied energy or end-of-life deconstruction costs. And smaller homes typically require less energy for their operation. Of course, water conservation, maintaining good indoor air quality, using resources efficiently, embodied energy, and site impact also come into play.

Passive Energy Measures

As a green designer eager to start a new project, I was happy to hear from builder Gary Dorris when he called me in June 2012 to talk about an interesting one. We had worked together on an Earth Advantage Platinum-certified home a couple of years ago—the beginning of a great working relationship.

Gary wanted me to meet Brad Hagen and Linda Niehaus, who were moving to southern Oregon from central Washington. Gary told me they wanted to build an energy-efficient home, but needed help with the design. From the beginning, Brad and Linda knew they wanted their new home to be energy-efficient and oriented for  passive solar gain as well as for active solar systems.

Beyond the thermal performance of their home, Brad and Linda had simple design requirements: a single-story, two-bedroom modern home. They also wanted to keep it around 1,000 square feet, which I’m delighted to say is being requested more often these days—the philosophy of living simply is resonating with a broader segment of the population. Much of what I know about smaller living spaces I have learned from architect and author of the “Not-So-Big” books, Sarah Susanka: Quality is better than quantity, define spaces without walls, light is good, and details in the finish can make your home unique and personal.

The first lot Brad and Linda looked at failed to work because of the neighborhood covenants, conditions, and restrictions, which did not allow a modern design. But Linda knew what she was looking for and it did not take too long to find an alternate site: a narrow lot, 45 feet wide by 120 feet long, with a good solar window. Only 10 blocks from the center of town, it was good location for easy access to services.

Envelope Efficiency

I attempted to simplify the decision-making process by offering three different design levels for the building envelope. Gary had worked with several homes constructed with structural insulated panels (SIPs), and appreciated the ease and speed with which the envelope could be assembled, so I specified SIPs for the entire envelope.

Level one was the “green” package, which exceeds the existing Oregon building energy codes for R-values. This design includes R-24 SIP walls, an R-40 SIP roof, and 2 ACH50 (air changes per hour at a pressure of 50 pascals—see “Build It Tight, Ventilate It Right” sidebar). “Greener” is a good step up, with R-32 SIP walls, an R-48 SIP roof, and 1 to 2 ACH50. Both levels one and two were estimated to cut thermal bridging by about 40% compared to standard stud construction. This improvement can result in heating and cooling energy savings of 15% to 20%.

Comments (2)

DawnLarisa's picture

We have magnesium anode in our solar heater. Corrosion inhibitor decreases the corrosion rate and protects the metal tank.

Marc Fontana's picture

The article mentions that the Solar Water Heating system uses water with a corrosion inhibitor as the heat transfer fluid. What is this corrosion inhibitor? How frequently does the fluid need to be changed?

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