One of Austin Trautman’s heroes is Joseph Eichler, a midcentury California developer who brought beautiful architecture to the masses.
Eichler, however, didn’t bear the burden of knowing how energyinefficient all those expansive glass walls, skylights and atriums could be.
Trautman, an environmentalist with a degree in kinesiology from Arizona State University, does.
He has spent the past three years researching the best way to build a net-zero energy home, east of downtown Phoenix, that produces all the power it consumes.
Trautman tagged Valley architect Matthew Salenger of CoLAB Studio and builder James Trahan of 180 Degrees, known for building some mammoth modern luxury homes, to create a prototype that celebrates both modern design and green building.
“I like big puzzles,” Trautman, owner of Vali Homes, said from the finished house, where he talked in detail about its airtight building envelope, lack of waste during construction and its efficient wall system with “half the wood and three times the insulation of a typical home.” Because the home is relatively small, with airtight walls and well-placed windows, a 3.6-kilowatt photovoltaic solar-energy system will power it.
Although the Valley has plenty of inefficient older houses, Trautman’s project is one of many that is challenging standard homebuilding practices and pushing energy-efficient technologies.
Another was just completed in north Phoenix, where a team of architecture, engineering and construction students from ASU and the University of New Mexico collaborated to create a net-zero energy home — one that is also transportable.
On Thursday, the ASU/UNM team will compete against 19 other entries at the U.S. Department of Energy’s Solar Decathlon in Irvine, Calif. The event is a Super Bowl of sorts for solar-powered homes aimed at creating a new generation of builders who think green.
The event is held every two years, because it takes that long to dream up, engineer and construct these sustainable homes, which are judged on performance, affordability and livability.
One of the biggest innovations in ASU/UNM’s 850-square-foot SHADE home (an acronym for Solar Homes Adapting for Desert Equilibrium) is a radiant heating and cooling system that uses water-filled capillaries above a plaster ceiling as a way to cool or heat the home. The capillary system is made by Beka USA in Goodyear.
“It’s an effective system,” said Alia Taqi, an ASU graduate student on the decathlon team. “It works really well in dry climates, and it’s a little more costly than a traditional HVAC cooling system. But, in the long run, it uses almost 40 percent less energy.”
SHADE cost about $285,000 to build and will produce all its own energy, saving an estimated $150 per month compared with a conventionally built home of the same size. Net-zero homes tied to the grid pay only the minimum monthly fee to their utility company — about $10 to $17 per month for billing and meter reading.
The team is also testing material in the floors that absorbs energy when a room is warm and releases it when the temperature drops, evening out a room’s thermal profile.
SHADE also is testing a thermal battery (used in some commercial buildings) that freezes water at night and uses ice during the day for a glycol and water solution carried to the cooling systems.
Interior walls coated in clay plaster help regulate humidity in SHADE, and a tilted solar array serves as a roof over a 200-square-foot porch that extends the living space. An exterior screen of 2-by-4s, meant to mimic the look of cactus needles, helps shade the exterior walls.
Next year, a SHADE home will be installed at Steele Indian School Park as an example of sustainable living as part of the city’s Phoenix Renews development plan.
C.R. Herro, vice president for environmental affairs at Meritage Homes in Scottsdale and an industry leader in green-building technology, said he believes heating and cooling systems that use liquid rather than forced air may be the future. They’re considered more efficient and more comfortable. But, he said, it will take time for the systems to become affordable.
Herro, who will speak at the Department of Energy’s net-zero energy summit during the Solar Decathlon, said he remembers when the event’s net-zero energy homes seemed like spaceships.
Today, he said, net-zero is a no-brainer. Since 2011, Meritage sells only Energy Star-certified homes that, with optional Echo photovoltaic solar-power systems, can achieve net-zero status.
Meritage’s net-zero homes start affordable — in the $200,000 range, depending on location. And several local homebuilders offer solar packages. Herro admitted it’s not the average customer who understands and opts to invest about $30,000 in solar panels to create a net-zero Meritage home.
Local utilities and Arizona SmartPower, a non-profit that helps educate homeowners about solar choices, say it’s hard to find many true net-zero homes in the Valley that create all their own power, because air-conditioning uses so much energy in the summer months.
Ed Fedoruk, a custom homebuilder who used to sell photovoltaic systems, is a net-zero homeowner. Fedoruk said he pays Arizona Public Service Co. $10.54 per month — the utility’s minimum monthly charge for meter reading, billing and having an account — to power his 3,000-square-foot Carefree home.
“It’s not science fiction,” Fedoruk said of living in his net-zero home, which is well-insulated and powered with a 6-kilowatt Sanyo solar-power system. “It’s like living in any home, really. … You don’t have to worry about scrimping on the air-conditioner. When you don’t have big electricity bills, it helps with the budget.”
Herro said the challenge going forward is educating consumers and adopting technologies that continue to make homes increasingly energy-efficient and extremely durable — even stormproof.
For that, many companies are testing new wall systems that are superior to standard wood framing with fiberglass-batt insulation.
This past spring, in time for Earth Day, Meritage unveiled a new prototype green home in Goodyear using a poured-on-site wall system of insulated concrete panels by the Arizona company HercuWall. The 7-inch- thick walls are quiet, watertight and resistant to mold and termites.
Nathan Day, a luxury-home developer at Sterling at Silverleaf in north Scottsdale, is testing energy-efficient wall panels by i-Frame Building Solutions in Scottsdale (used mostly for commercial buildings) that employ steel studs and embedded interlocking insulation.
In Phoenix, Trautman’s spec home has another feature that Herro has mentioned as a homebuilding technology of note: vented siding.
From the outside, the Vali home looks like a modern, steel-wrapped rectangle. The envelope of perforated steel panels keeps radiant heat off the insulated exterior walls and vents heat. Under the steel siding, the walls boast foil-wrapped rigid-foam insulation, blown-in cellulose insulation and wooden studs placed 24 inches apart rather than the typical 16 inches.
Trautman said they took great pains during construction to seal any air gaps using flashing tape, rubber gaskets and polyurethane foam. He also installed a fresh-air system that helps eliminate dust and contaminants and recirculates the air in the home every three hours.
“The airtight construction, less wood (because wood is a poor insulator), more insulation and a fresh-air system are currently somewhat specific to green building, but I’m certain (they) will be standard in the next 10-20 years,” Trautman said. “Minimum codes are moving steadily in this direction, and many of the ideas we have used are already standard in places like Canada.”
A lot has been cleared for construction on another Vali home. Trautman has listed the first 1,500-square-foot home for $400,000 — $266 per square foot, or more than 2.5 times the median Valley home price.
Ultimately, Trautman hopes to continue building, making the modern green houses more affordable. A good portion of the initial cost is research and development, but Trahan, Trautman and Salenger say that after months of running the plans through modeling programs that estimate cost and energy efficiency, they were able to get the initial building cost down to about $140 per square foot — or about $210,000, not including the landscaping and steel cladding around the courtyard.
“It did become a big balancing act,” Trahan said. “We went through hundreds of line items of cost.”
Trautman would like to find a city lot large enough to build several at once, further lowering the cost to customers.
Overall, he said, his goal is to create houses that are so peaceful, comfortable, durable and well-designed that the green features don’t call attention to themselves — they simply work.
“Apple and Tesla are probably my favorite companies as examples,” he said. “It’s not so much about all the features (the iPhone) has — it’s extremely simple, it’s got one button, somehow it intuitively works well, and I use it because it’s not a pain. … Hopefully, that improves your life rather than adds complication to it.”
That, he said, is how we should build a house.
