Heavy snowfall causing increase in roof troubles

By KBJR News 1

March 10, 2014 Updated Mar 10, 2014 at 6:40 PM CDT

Duluth, MN (NNCNOW.com)--- Sunday night, a Wal-Mart store in Forest Lake, Minnesota was evacuated after snow heavy endangered the integrity of the roof.

A few weeks ago snow caused the roof of the Nauti pine Bar in Hayward to collapse...and the party barn at the Buffalo House fell in under the weight of snow earlier this winter.

Because of the extreme snow fall this season, U-M-D's Civil Engineering leaders are talking about what the damage heavy snow fall can do to roofs.

This winter has dropped more than seven feet of snow on the Northland. Experts at U-M-D are calling it an extreme event leading to the highest number of roof collapses since the 19-80's.

"the weight of the snow not melting and staying on the roof and accumulating on the roof is increasing the amount of snowload we have on the roofs," said Rania Al-Hammoud, an Assistant Professor in the Civil Engineering Dept. at UMD.

When buildings are designed, the type of roof, as in sloped or flat, are considered. The type of roof selected changes how the wind shifts the snow drifts and melting patterns.

"When we design for roof snow we consider about 80 percent of the ground snow load and that also, as I said, varies depending on the structure of the building," said Al-Hammoud.

Structures such as hospitals and airports are designed to withstand the excess snowfall. As new buildings are put up, there is also a change in design codes to prepare for higher snow loads. But it seems living in a place, where we bear winter's wrath, many month of the year, we tend to be pretty prepared.

"Houses and buildings are designed to live in Duluth and for the most part they can handle it pretty well," said Asst. Professor Mary Christiansen in the Civil Engineering Dept. at UMD.

Now is also the season for ice dams, which could cause water damage in your homes. Christiansen says the structural damage to your home slowly progresses.

"Water, as we know, is damaging to wood and all other sorts of materials so most likely if it's not a failure right now, it may become one, so it needs to be addressed," said Christiansen.

Catching a small problem before it becomes a big one.

The experts at U-M-D say today's buildings are designed for a higher snowload than the 19-50's.

Written and posted to the web by Raeanna Marnati