One-of-a-kind house: In the city, off the grid

When Randy and Janna Hafer finish their house on the North Side of Billings sometime next year, it won’t look all that different from other houses in the neighborhood.

There will be one noticeable difference, though — the 23-foot-high wind turbine on the corner of their lot at North 23rd Street and Seventh Avenue North.

Much more important will be the differences that passersby won’t see, differences that will make the house the first of its kind in Montana and one of the first of its kind in the country.

The “Urban Frontier House,” as Randy Hafer is calling it, will eventually be completely off the grid, meaning there will be no city water or sewer hookups and no connection to off-site power. It will ultimately be a “net-zero” house, using no more energy or water than it generates on-site.

Power will come from photovoltaic collectors and the wind turbine, and most of the heating and cooling will be provided by insulation, ventilation and passive solar. All the water will come off the roof, collected in barrels and stored in the basement.

They will grow a lot of their own fruits and vegetables in a 300-square-foot garden room, which will also serve as a passive heat collector used to warm the house. If it gets really cold for an extended spell, they could plug in electric heaters, using electricity stored in batteries in the basement.

They plan to be on the power grid for at least a year, to make sure they’ve optimized their own system before leaving the grid. Hafer talked about the power supply question in his characteristically optimistic, slightly self-deprecating way.

“We don’t have a heating system in the house,” he said, then laughed before adding, “which is still sort of an experiment.”

Hafer has been experimenting for a long time. He is the president and Janna is the CFO of High Plains Architects, which they founded in 1999. High Plains has worked on six building projects in Billings, Red Lodge and Wyoming that achieved LEED Platinum status, the highest rating granted by the U.S. Green Building Council.

Hafer said he has been seriously into green building since 2005, when High Plains completed the Billings headquarters of the Northern Plains Resource Council, its first LEED Platinum building.

“We all learned a ton,” he said of that project, “but we also learned there was a lot more that we could do.”

Hafer, a native of Billings, dates his interest in sustainable building techniques back to 1972, when he left Montana to study architecture at Stanford University in California. He experienced the energy crisis of the mid-1970s in a densely populated urban area jampacked with cars, and he began thinking of a world in which oil was no longer cheap or plentiful. About the same time, he read a book about building a self-contained, off-the-grid house.

“I just thought, ‘what a cool idea,’” he said. “This has been my quest ever since then.”

A house that Hafer built for his family in Billings in the early 1990s had a garden room, lots of ventilation and construction materials similar to what he’s using in the new house, but it wasn’t in the same category as the new house.

Part of Hafer’s goal with the new house is to have it certified through three programs. He wants another LEED Platinum rating, for starters, plus certification from the Passive House Institute. He also wants to meet the Living Building Challenge to earn certification from the International Living Future Institute in Seattle.

James Connelly, manager of the Living Building Challenge for the institute, confirmed what Hafer said — that no residential projects have yet been granted certification, though four or five houses are under construction or are waiting the requisite year of habitation needed to document performance.

“A whole lot of what this house is, is place,” Hafer said. “In our climate, insulation and ventilation are key.”

During a TEDxBillings presentation at the Billings Public Library last January, Hafer elaborated on the importance of place.

“It’s so simple if you just position the house to take advantage of what that local place has to offer,” he said.

That’s one reason he’s using solar collectors and a wind turbine. Seasonal variations in the position of the sun, relative cloudiness and the frequency of wind mean that one or the other system will be working best when the other is at lower capacity.

And because Seventh Avenue North faces 36 degrees east of south, the garden room, atop which the photovoltaic cells will sit, will be skewed to face directly south. Every habitable room in the house will have direct high-low ventilation.

“If you don’t have air moving outside, cross-ventilation doesn’t work,” Hafer said. You need to “pull the cork” by having windows near the floor and others up high, in the ceiling if need be. Opening the high windows pulls the cork. The warmer air rises up and out, the cooler air flows in below.

“This is real basic stuff,” Hafer said.

The insulation started with the basement, the foundation for which was poured last week, using 100 percent fly ash, a byproduct of burning coal, rather than cement. There are 16 inches of foam insulation under the slab and eight inches under the footings.

That heat trap will keep the basement at a steady temperature of about 75 degrees, which will also help heat the floor above it.

The roof will be heavily insulated and the walls will be made of structural insulated panels — two sheets of OSB (oriented strand board, similar to plywood) with 5½ inches of foam insulation in the middle — manufactured by Big Sky Insulations in Belgrade. Windows will have two sets of blinds, one an insulated blind, giving the windows an R-value of 20, as high as the R-value of some walls in conventional construction.

As for water, with 9,000 gallons of storage capacity, Hafer is confident they will always have enough because their needs will be so limited. They will have low-flow fixtures and a composting toilet — made in Whitefish — that will flush with just a pint of water, 10 to 20 times less than conventional toilets, the biggest users of water in a typical house.

Some of the water will be filtered to make it drinkable, but all the gray water, used for showers, laundry and such, will be filtered and re-used indefinitely. Some of the gray water will also be used for irrigation.

With electricity, the same concept applies. They hope to produce all they need because their needs will be small. They will have energy-efficient appliances and LED lighting, and the power generated on-site will be DC rather than AC.

Some of it will be converted to AC, but the mechanical equipment in the basement will run on the more efficient DC power, as will the refrigerator. As a result, the refrigerator, the greatest user of energy in most houses, will be 90 percent more efficient than a typical unit.

Other important considerations are that the house, which is expected to be done in six or seven months, will be comfortable, attractive and affordable.

“You’ve got to do this in a way that excites people, that makes them want to live in the building,” Hafer said.

The house will be 2,400 square feet and will cost about $140 a square foot, close to the average cost of conventional residential construction, Hafer said. It will also be scalable and replicable, he said.

If he can build a house like this in Montana — which has a larger spread between its record-low and record-high temperatures than any other state — it should be obvious that a similar house can be built anywhere on the planet, Hafer said.

And because they want the house to serve as an educational tool, the Hafers plan to erect explanatory panels alongside the house, explaining how the house and all its various components are being built and how they work together. They also plan to document the building process on a blog that will be attached to the main page of High Plains Architects.

The novel building plans took five months to go through the city of Billings’ review process, partly because of the volume of information presented. Hafer said the plans included 150 pages of structural calculations.

The project also needed variances from the state Department of Environmental Quality, because there was no connection to city water, and the Yellowstone County Health Department, because of no connection to the city sewer system.

Hafer credited Dave Mumford, director of the city’s Public Works Department, for obtaining those variances.

“Dave gets it,” Hafer said. “He was very receptive.”

Mumford, for his part, said his job was mostly putting Hafer in touch with the people he needed to talk to. But he said he also wanted to help because he didn’t want the bureaucracy to say no just because a project was too innovative.

The agreement they worked out is that Hafer will maintain the existing water and sewer stubs on the property — there was another house there, decades ago — so they can be hooked up immediately if there are any problems with Hafer’s own water and composting systems.

“It’s not a simple system,” Mumford said. “It will be interesting to see how it works.”

There would have to be tens of thousands of such projects before there was any major impact on the city’s water and sewer systems, he said, but the experimentation has to start somewhere.

“I give Randy a lot of credit,” Mumford said. “He’s living what he’s been preaching.”

UPDATE: Although the blog is not yet live, there is a project page on the High Plains Architects site.

 

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