After weekend collapse, Grand Forks Fire Department, contractor urge homeowners to keep roofs clear

GRAND FORKS – Following a roof collapse at the South Towne Square mall, the Grand Forks Fire Department and local roofing contractors are urging homeowners and businesses to keep their roofs clear of snow if possible.

The collapse occurred on Saturday evening during Blizzard Emily, which dumped 11.5 inches of snow on Grand Forks between Friday and Sunday according to Jim Kaiser, meteorologist at the National Weather Service’s Grand Forks Office.

Delray Huot, battalion chief at the Grand Forks Fire Department, said excessive snow buildup and the building’s flat roof contributed to the collapse.

“Snow doesn’t typically blow off of flat roofs,” said Huot. “It depends on how much snow you get and how wet the snow is, but this one appears to be just a buildup of snow over the winter.”

Hout said the mall will be closed “for a while,” while structural engineers work on “shoring” the rest of the building, a process of building braces to support the remaining roof structure from further collapse, and protect the mall's other tenants from damage.

“If one part of the roof has failed, there is a high probability of another failure,” said Huot. “The way roofs are constructed, if one part fails, the other load carrying members have to carry the remaining weight.”

There are 14 businesses affected by the closure.

Huot said the collapse also triggered a gas leak at the mall, which emergency personnel responded to contain on Monday.

Huot encouraged removing snow from roofs — especially flat roofs — if possible.

“I would advise homeowners and business owners — especially after this last storm — to use roof rakes to get the snow off of their roofs if they can,” said Huot. “If it’s too deep, there are removal services that can help.”

Todd Schmidt, project manager and estimator at Skinner Roofing in Grand Forks, said changing temperatures and snow levels throughout the winter have made assessing the amount of stress put on roofs difficult.

“This year’s been so goofy with snowfall,” said Schmidt. “We got a bunch, then it warmed up a bit, turning to ice and water. It’s really hard to tell how much weight is on some of these roofs.”

In addition to flat roofs, roofs supported by wooden frames are more susceptible to collapse under heavy snow weight, according to Schmidt.

“Wood frame roof structures — like the one that collapsed — don’t have as much load bearing capacity,” said Schmidt.

Schmidt also said evidence of a compromised roof can be visible inside of a building before a collapse.

“If a roof starts bowing, you can see it from the inside,” said Schmidt. “Sometimes doors won’t open or close, because of pressure from the top.”

Like Huot, Schmidt encouraged homeowners and businesses to keep their roofs clean.

“If people are not comfortable with throwing a ladder up and looking at their roofs themselves, I’d tell them to call someone to come check,” said Schmidt. “Most roofs will be able to handle 10 or 11 inches, but there are some that have a lot of weight up there.”