A Building Code With Room for Innovation
Jeff Whitney, the head building inspector in Grand County, Utah came by the straw bale construction site in Moab where my wife and I are volunteering. He needed to inspect the flashing and some other details before we applied our first coat of plaster to the exposed bales.
Straw bale construction is not recognized in the Utah state building code, but because of Mr. Whitney, Grand County is the only place in Utah where it is explicitly allowed. In fact, the county’s straw bale construction provisions are right on his office’s home page.
“Other jurisdictions around the state used to say, “hell no, “ said Mr. Whitney, who wears a cowboy hat and white mustache, “But now they are starting to call us.”
Section 104.11 in the Utah state building code is titled “Alternate Materials and Methods.” It gives county building inspectors the latitude to approve a construction method not spelled out in the code if they have been shown data that convinces them that it is safe and reliable. Mr. Whitney says he is willing to listen to any proposal as long as it comes with hard data.
If Mr. Whitney approves an experimental material that fails, then the county can be held liable by the next family to buy the home.
“The new owners take over and they find out they have rot problems or termite problems or mold problems — they look to sue somebody,” said Bill Hulse, another Grand County building inspector.
“I’ve been here 24 years and never been successfully sued,” Mr. Whitney said. “Been to court a lot, though,” he added with a grin.
Moab is a small but vibrant outpost of the natural building movement with a committed cadre of builder/advocates. For several decades, Moabites who wanted to build with straw bales lobbied Mr. Whitney. So they brought in engineers to explain why straw bales wouldn’t rot in the walls if installed properly. They presented laboratory tests conducted by an engineer, Bruce King, proving that straw bales meet and exceed fire safety requirements.
As Mr. Whitney began approving straw bale projects in the county, he hewed closely to standard wood frame construction codes. But experts convinced him that some requirements that he insisted on actually hurt the bales. For example, Laura Bartels, a green consultant, showed Mr. Whitney that wrapping the building in a moisture barrier like tar paper or Tyvek traps interior moisture in the bales and promotes rot. Research demonstrates that straw bales covered in a breathable plaster that allows moisture to escape perform best.
“So we get more information, and we’ve adjusted our policy a few times,” Mr. Whitney said.
But straw bales are only the tip of the natural building iceberg. Moabites experiment with all sorts of techniques not found in the Utah building code. For example, earthbag construction involves packing woven polypropylene bags with adobe and stacking them to create domed structures that would be at home on Tatooine.
Donald Kiffmeyer and his wife, Kaki Hunter, were inspired to build their first earthbag hut in the 1990’s while working on a movie script about a single mother’s quest for affordable housing. Two decades later, the Hunter-Kiffmeyers are not licensed architects, engineers or contractors, but they have become experts in earthbag as well as other unconventional building techniques, including lime plaster.
They even wrote one of the definitive books on the earthbag construction,“Earthbag Building.” (Mr. Kiffmeyer was the first building instructor forCommunity Rebuilds, the nonprofit sponsoring our current build, when the group first got off the ground, but he is no longer officially affiliated with it.)
“We are really into R and D,” Ms. Hunter said with a laugh. “We experiment at home with a lot of stuff.”
Last week, Ms. Hunter walked into Mr. Whitney’s office with a stack of documentation to convince him to approve an unusual way to insulate the walls of a kitchen addition. She wants to take loose straw, coat it with clay, pack it tightly together in a foot thick wall cavity, and cover it with a lime plaster. The technique, known as light straw clay, has been used for centuries in Europe, Ms. Hunter says.
Mr. Kiffmeyer said that Mr. Whitney showed “real leadership” when he instituted a straw bale policy in Grand County and that he and Ms. Hunter were hopeful they could persuade him to approve their new technique. “Jeff, he does his homework,” he said.
Mr. Whitney said: “They want us to stick our neck out. We are more than willing to do it, but give us the numbers.”
Among the documents that Ms. Hunter gave Mr. Whitney was a 148-page report on research submitted to the Canadian Mortgage Housing Corporation. The building inspectors were initially skeptical about the source. “The studies weren’t done by a recognized agency,” Mr. Whitney said initially.
Ms. Hunter and other advocates say that testing is one major barrier preventing natural building practices from getting into building codes. The International Code Council requires rigorous, expensive laboratory testing for fire rating, structural integrity, moisture permeability and a host of other criteria.
Before he did some of the testing himself, Mr. King wrote in his 1996 book “Buildings of Earth and Straw,” that with a few exceptions, “neither earth nor straw can be patented or turned into a salable products, so industry has not seen much incentive to sponsor expensive structural tests.”
The Grand County inspectors agree. “The testing is where the issue is,” Mr. Hulse said. “The green movement doesn’t have the funds to do the testing.”
They wonder why. “We can drum up a lot of money to save the whales from our front porch,” Mr. Whitney said. ”Why can’t we save the planet with some good natural products?”
After doing some research, Mr. Whitney said he thought the methodology of the Canadian light clay straw tests was sound and that he was leaning toward approving the building permit. But he said he might require Ms. Hunter to include language in her deed informing any future owner of the house that an experimental building technique had been tried in the kitchen walls and Grand County cannot be held liable.
There are still some natural building practices that Mr. Whitney said he was not ready to approve. For example, his wife is from Chihuahua, Mexico, where her family sends the kids out to repair small cracks and divets that develop on the exterior of their adobe homes during the winter. It’s a type of yearly maintenance accepted as a way of life there. But the average American won’t buy such a home, believing it to be an unneeded hassle, the inspector said. “The culture in our country doesn’t allow for continuous maintenance,” he said.
He also refuses to allow construction of straw bale house designs in which straw and plaster hold up the roof with no wooden structure — known as load-bearing straw bale. The problem, he said, is no standard exists for manufacturing the individual straw bales.
Most building products are manufactured to specifications, and the inspector can assume they will perform in a certain way. But straw bales are made by farmers in the field, and their density, weight, size and moisture level, – and even the grass species used to make up the straw — can vary significantly. Mr. Whitney said that an engineer cannot reliably predict how much weight a bale can support or how it will react during an earthquake or hurricane. “If at some point we have a standard and I could test it against what’s being used, I’ll allow it,” he said.
Still, Mr. Whitney said he is willing to consider permitting more alternative building methods.
“I’d like somebody to come in with cobs,” for example, he said. “This department is the last department in the world that wants to stop green construction or innovation, or inexpensive construction. But you still gotta meet standards.”
Original Post by Rob Harris, NYT
A Building Code With Room for Innovation
