In order to meet the carbon reduction goals that are necessary to avoid a global climate catastrophe, almost every U.S. home will need a deep energy retrofit. In most cases, the work will require walls and roofs to be covered with a thick layer of rigid foam.

The logical time to do this work is when siding or roofing is replaced. It stands to reason, therefore, that siding and roofing contractors should:

• Educate themselves on the building science issues surrounding exterior foam insulation;
• Be familiar with techniques for installing rigid foam under new siding or roofing;
• Regularly suggest that customers consider including thick exterior foam under new siding or roofing.

Unfortuntately, few siding and roofing contactors have taken these steps. Although the upcoming need for massive numbers of deep energy retrofits is understood by many climate scientists and energy experts, this type of work isn’t on the radar screen of most contractors. In fact, customers who are interested in exterior foam retrofits have to search far and wide to find a siding or roofing contractor familiar with the required details.

Most contractors aren’t interested
A friend of mine, Karyn Patno of St. Johnsbury, Vermont, replaced the asphalt shingle roof on her home this year. About half of her house has a cathedral ceiling insulated with thin fiberglass batts.

“After several years of ice dams and leaks, I decided to replace the shingles with a standing-seam metal roof,” Karyn told me. “I thought it would be a good idea to add insulation to the roof at the same time.” She was willing to consider bids for new rigid foam on top of the plywood sheathing or spray polyurethane foam between the rafters.

“I contacted four area roofers,” Karyn said. “Two of them said that they don’t remove the shingles but put the metal roofing directly over the old shingles, and that this method ‘would provide enough added insulation.’ One roofer said he could remove the shingles but was not interested in adding any insulation, because he ‘didn’t do that work.’ The fourth was a builder who also does roofing. He was the only one willing to provide a bid to add insulation along with the new roofing. He suggested removing the shingles, taking off the plywood, adding closed-cell spray foam insulation, replacing the plywood, and putting on the metal roof. Interestingly, this roofer’s bid was not was not the most expensive.”

Siding contractors don’t like thick foam
Intrigued by Karyn’s story, I decided to call several siding and roofing contractors and ask about exterior foam. First I spoke with Carl Beatty, the owner of Beatty’s Builders in New Philadelphia, Ohio. “Customers don’t usually request or care about foam under siding,” said Beatty. “People don’t have the money. They’re just looking for the lowest price.”

Mike Krumm, the owner of Krumm Siding and Roofing in New Richmond, Wisc., said, “People are being led to believe that 3/8 inch of foam is plenty. In any case I have noticed that not many people are willing to pay the extra money. I’ve never had anyone ask for thicker foam, nor have I pushed it.”

Jeff Kaliner, the CEO of Power Windows and Siding in Brookhaven, Penn., told me, “If someone wants an additional layer of insulation, the windows would look sunken in, so we don’t do that.”

I also spoke with John Fiderio, one of the owners of Fiderio & Sons, a remodeling company in Meriden, Conn. Like the other contractors I spoke with, Fiderio doesn’t install thick foam under siding. “As a rule, we use 1/2-inch-thick foam from Dow — or at most 3/4 inch,” Fiderio told me. “When you start going thicker than that, you have to build out your windows.”

Nor does Fiderio recommend foam under new roofing. “In years past, we did some jobs with foam — generally over a cathedral ceiling. But we haven’t done it in years. If there’s an ice dam problem, we usually address it with Ice & Water Shield.”

“Call somebody else”
I also spoke with roofers. William Rodd, one of the owners of Rodd Roofing in St. Johnsbury, Vermont, told me, “If someone asks for foam, we say, ‘Call somebody else.’ We have enough problems without the foam.”

On the other hand, Chad Jackson, an estimator for Bliss Roofing in Clackamas, Oregon, appreciates the advantages of rigid foam under roofing. “If someone asks for foam insulation, we can do it,” Jackson told me. “But hardly anybody asks for it. Even if they know about the advantages of foam, they won’t do it, because everybody’s cheap. But as time goes on, foam insulation will become more necessary. Right now, all these roofing contractors say they don’t want to do it. But ultimately everyone will have to do it.”

A chicken-and-egg problem
To be fair to the contractors I interviewed, there’s no reason to expect contractors to promote thicker insulation when few customers ask for it. It’s a classic chicken-and-egg problem.

The only ones who seem distressed by the current status quo are energy nerds and policy wonks, may of whom see steep carbon taxes on the horizon. For those looking ahead, it’s painful to see new siding and roofing being installed over OSB or board sheathing. Each time that happens, another opportunity has been lost.

More information on deep energy retrofits
"An Old House Gets a Superinsulation Retrofit"
"The History of the Chainsaw Retrofit"
"Deep Energy Retrofits"
R-etro interlocking insulation system
"Retrofitting Exterior Insulation"