How much snow is too much snow on the roof?

Odds are the roof is safe. It won’t cave in from the snow; however, there may be too much snow on the roof. Learn how to determine those factors and remove the risks.

The weight of the snow

The critical factor in determining excessive snow loads on a roof isn’t the depth of the snow, it’s the weight, says home improvement expert Jon Eakes. That’s because wet snow is a whole lot heavier than dry, fluffy snow. In fact, six inches of wet snow is equal to the weight of about 38 inches of dry snow. That’s a huge difference!

The good news is that roofs are required by building codes to withstand the heaviest snows for each part of the country. “Theoretically, if your roof is built to code, it’s built to support more than the normal load of snow and ice,” says Eakes. Determining if the snow is wet or dry is simple—try lifting a few shovelfuls. In addition, watch the local weather forecasts.

Interior doors are a clue

If the interior doors begin to stick, that signals there’s enough weight on the center structure of the house to distort the door frame. Ignore doors on exterior walls but check interior doors leading to second-floor bedrooms, closets, and attics in the center of the home. Also, examine the drywall or plaster around the frames of the doors for visible cracks. Homes that are most susceptible to roof cave-ins are those that underwent sloppy renovations. Improper removal of interior loadbearing walls is often responsible for catastrophic roof collapses from snow.

Removing the snow

“People die every year climbing ladders,” said Eakes. “Add ice and snow and you’re really asking for trouble.” Instead, call a professional snow removal contractor to safely do the job. Check to make sure they are licensed and insured and expect to pay $250 to $500 for most jobs. The professionals use special gear, including sturdy extension ladders, properly anchored safety harnesses, and specialized snow and ice-removal tools. Don’t expect (or demand) a bone-dry roof at job’s end. The goal is to remove “excessive” weight as opposed to all weight. Plus, any attempt to completely remove the bottom layer of ice will almost always result in irreparable damage to the roof.

If the home is a small, one-story bungalow where the roof is slightly off the ground, taking matters into one’s own hands may be safe — while working entirely from the ground and with the right tools. Long-handled snow rakes work great on freshly fallen snow, and at $45 they are relatively affordable. Look for models with sturdy telescoping handles and built-in rollers, which keep the blade safely above the shingles. More expensive versions work by releasing the snow from underneath. These models slide between the roof and snow, allowing gravity and the snow’s own weight to do most of the work.

This article provided through a partnership between the St. Louis Post-Dispatch and St. Louis REALTORS®. Visit for more articles like this. By National Association of REALTORS® HouseLogic.

National Association of REALTORS HouseLogic