Roof collapse threat in the U.S. Great Lakes area as massive snow melts

Erie County Sheriff's Office Massive roof collapse.

Several roofs collapsed in the Great Lakes area last week as they succumbed to extreme lake-effect snow, totaling up to 7 feet. Now, even as the snow melts with warmer weather, the threat remains for more roof collapses.

For flat-lying roofs, gutters could still be jammed with packed snow, which could lead to additional collapse concerns. In a snowpack as dense as what the greater Buffalo area was covered in, Spamer said there could be nearly 4 inches or water held within snow.

The threat for structural damage is lower for angled roofs as the snow will melt and send water trickling down the side of the home or building.

A cold rain can also lead to heavier snow and more weight on a rooftop because when the rain falls it is then absorbed by snow already on the rooftop. As a result, the snow becomes even heavier than it was before the rain.

If the snow becomes too heavy, it can weaken the internal structure of a roof and cause damage or even cause the roof to collapse completely.

The type of snow that falls can also contribute to the likeliness of a roof collapse.

"There are different types of snow as well that can cause various damage," Paquette said. "A lighter, fluffier snow that falls with cold temperatures is a much different story than a wet, heavy snow with sleet and rain."

The more dangerous type of snow is the wetter, heavier snow due to its increased water content. This type of snow is most common around areas in southern New England.

To prevent a roof collapse or damage due to snowfall, keep tools handy that allow for timely and easy snow removal after a storm.