Odell Park barn collapse

The city-owned storage barn in Odell Park collapses from the weight of snow on Wednesday night. (CBC)

After three roofs collapsed under the weight of snow in the Fredericton area last week, a city official is urging residents to watch for the warning signs of roof stress.

Mike Pospolita, the manager of the building inspection division, said one sign of possible trouble is a big increase in the binding of doors or windows.

"Creaking, popping sounds from the roof, grinding sounds or gaps. If you see new gaps or larger gaps than you're used to seeing in the winter — those are all signs that you might be in trouble," he said.

Pospolita says clearing the snow off roofs can help, but advises it should be done by a professional.

Some people make the problem worse by clearing snow from one side, which puts more weight on pressure on the other side, he said.

The region has one of the biggest snow loads it has had since about 1998, but snow depth isn't the only factor when it comes to roofs, Pospolita said. Snow density also matters and the freeze and thaw cycles haven't helped.

Roof structures with trusses are most effective because the weight loads goes down the walls to the foundation, whereas older rafters tend to spread and can push the walls out, leading to failure, he said.

If homeowners are concerned, they should bring in an engineer or another qualified expert for a second opinion, said Pospolita

In the event of something extreme, such as a window breaking, they should get out of the building immediately, he said.

The roof of a large storage barn in Fredericton's Odell Park collapsed on Wednesday night under the weight of snow. The large barn was the former home of the Fredericton Pony Club and used by the city to store equipment used to maintain parks.

A horse barn in Durham Bridge collapsed earlier that day, and the Best Metals building in a Fredericton industrial park also lost its roof earlier in the week after a winter storm blanketed parts of New Brunswick with about 40 centimetres of heavy snow and ice pellets.