Depending on cost, a project to replace the roof on the old Blaine County Courthouse could be changed to include heaters installed in roof valleys to melt snow rather than try to hold it on the roof.
The $1.36 million project is intended mainly to install a new roof and repair crumbling walls and roof structure at the top of the 19th-century, three-story brick building. However, it also has a public safety component, in that the roof’s shape and poor insulation have resulted in ice dams and slides of snow and ice onto the ground. That is especially problematic at the building’s rear entrance onto an alley between it and the county Judicial Building.
“It’s a miracle that nobody’s been killed over the years,” County Commissioner Larry Schoen said during a commissioners meeting Tuesday.
Project architect Steve Trout told the commissioners that his team had been operating on a plan initiated by construction consultants McKinstry Essention several years ago to avoid avalanches by holding snow on the roof.
However, he said, “As we got into this, we started to question the value of retaining snow at all times on these steeper pitches.”
Trout said the building’s two east-side towers, one built in 1907 and the other in the 1990s, have especially steep roofs.
He said that even though the project includes improving air circulation under the roof, there will always be heat transfer from inside the building, particularly at the roof’s edges where the insulation is thinner. Also, he said that even though the roof over the east-side alley can be designed to hold a foot or so of snow, upper layers could break off and slide whenever a weakness forms between them.
Trout said that by placing electric heat mats in the roof valleys, ice dam formation could be eliminated, greatly reducing the hazard of snow sliding off the roof over the alley. However, he said, the commissioners will need to decide whether that’s worth the as-yet-unknown cost.
“This project seems to be changing on a weekly basis,” Schoen said. “The project can’t keep coming up with solutions that cost more.”
However, he said, “It would be a shame if we completed the project and didn’t improve the safety of the building.”
Trout said he would research costs for the heat mats and report back next week. He said he would also find out how the mats have worked on other projects.
“All the indications are that it’s a good product,” he said.