If you’ve had a big snowfall in your area and you’re wondering if your roof  can stand the extra weight, don’t reach for a ladder and a shovel — reach for  the telephone. Calling in a professional to remove ice and snow from your roof  is the smartest — and safest — option.

When (if ever) is it necessary?
The critical factor  in determining excessive snow loads on your roof isn’t the depth of the snow,  it’s the weight, says home improvement expert Jon Eakes.
That’s because wet snow is considerably heavier than dry, fluffy snow.  In fact, 6 inches of wet snow is equal to the weight of about 38 inches of dry  snow.
The good news is that residential roofs are required by building  codes to withstand the heaviest snows for that particular 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.
You can  determine the type of snow you’re getting simply by hefting a few shovelfuls — you should be able to quickly tell if the current snowfall is wet or dry. Local winter  storm weather forecasts should alert you to the possibility that snow loads  are becoming excessive and a threat to your roof.

How do I know  there’s a problem?
An indication that the accumulated snow load  is becoming excessive is when doors on interior walls 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 your home. Also, examine the drywall or plaster around the  frames of these doors for visible cracks.
Homes that are most  susceptible to roof cave-ins are those that underwent un-permitted renovations.  The improper removal of interior load-bearing walls is often responsible for  catastrophic roof collapses.

The snow load seems excessive, now  what?
Most home roofs aren’t readily accessible, making the job  dangerous for do-it-yourselfers.
“People die every year just climbing  ladders,” Eakes points out. “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 — that immediately  sets them apart from inexperienced competitors.
Pro crews attack snow  removal with special gear, including sturdy extension ladders, properly anchored  safety harnesses, and special snow and ice-removal tools. Expect to pay $250 to  $500 for most jobs.
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 your roofing.

The  do-it-yourself option
If you have a small, one-story bungalow  where the roof is just off the ground, taking matters into one’s own hands may  be safe — if you can work entirely from the ground and have 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.
Other 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. Models range from $50 to $125 or more for  unique systems utilizing nylon sheeting. Again, search out models with sturdy  adjustable handles.
Eakes offers a common sense word of caution about all  these snow removal tools. “They tend to work their best on light, fluffy snow — the kind that probably doesn’t need to be removed in the first  place.”
You’ll need to anticipate where the snow and ice will fall as you  pull it off your roof — you won’t want to pull a load of heavy, wet snow down on  top of yourself or any helpers.
Remember, the goal isn’t to remove all  visible snow and ice, but rather just enough to relieve the excessive load on  the roof.