McClurg's Home Remodeling Blog

A Winter Warning for CNY Homeowners: How to Prevent a Roof Collapse

Posted by Scott McClurg on Thu, Feb 24, 2011

Roof Collapes on WSTM NBC-3Winter 2011 has caused considerable damage to roofs of Central New York homes. It seems like we’ve had snow on the roof continually since the first of December. Weather conditions in our region have been particularly harsh due to unprecedented lake effect snowfall and cold Canadian weather systems which have caused freezing on roofs and don’t allow for melts that we normally experience. Roofs are not designed to hold up to several tons of weight. On roofs that have collapsed, snow build up has been 2 to 3 feet thick.

What can you do to protect your home from a roof collapse? First and foremost, it is important that you maintain your roof and remove snow. According to a colleague in the roof repair business in Minnesota:

“As little as six inches of snow packed on your roof could cause major damage to your home—and your wallet. Institute for Business & Home Safety (IBHS) research shows about $1 of every $5 paid for home and business property losses in recent years has stemmed from damage due to freezing weather, snow and water leaks. Fresh snow is two to four times lighter than old snow, so your roof could hold up to four feet of fresh snow safely. But new snow on top of old snow can multiply the risk of collapse. Ice mixed with snow is extremely heavy—just one inch of ice can weigh as much as 12 inches of fresh snow.”

Do not let snow on your roof build up beyond 12 inches. Here are some tips for properly maintaining your roof in winter:

  1. You must use extreme caution any time you are on a roof, especially in ice and snow conditions. Clearing a roof can be very, very dangerous work. We suggest that this be done by a professional.
  2. Most roofs in Central New York are shingled with asphalt shingles that can be damaged if the proper tools are not used to remove snow. Tools you will need are a wood roof rake and a plastic shovel. Roof rakes are designed with an extension handle to allow you to draw snow down from the roof without having to climb onto it. The head of a roof rake is also designed to minimize damage to shingles. If you must climb on to the roof, a plastic shovel will minimize shingle damage.  Do not use an aluminum or metal shovel to remove snow from a roof.  If shingles are damaged, water will leak into your home.
  3. For safety’s sake, have someone outside with you when you are doing this type of work or someone at home who can get help if there is an accident.
  4. Before removing snow from a roof, clear the area below your roof to assure solid footing for you and a ladder, and to make a space for snow to land.
  5. Clear snow off skylights.
  6. Carefully remove icicles, stand clear. Icicles can weigh hundreds of pounds and can cause injury or damage. If you are too aggressive in removing icicles you can damage roofing shingles.
  7. Begin removing snow from the lower sections of the roof in narrow strips. Remove snow evenly from both sides of the roof so that the weight of the snow is not significantly greater on one side.
  8. If you are using a ladder, be sure that it is secure. Remove snow in small scoops to maintain your balance. You don’t have to clear the roof completely. In fact, by maintaining a light layer of snow, you will minimize ice dams.
  9. Do not pile snow from upper roofs on to lower roofs.
  10. There is no quick fix for snow removal. Never use a snow blower to remove snow from a roof. Chemical products used to melt snow may void your roof’s warranty or can cause damage to your landscape. Roof cables can be problematic in our CNY winters and add considerable cost to your energy bills.

Removing snow from icy roofs is a risky business. People can get injured in the process or cause costly damage to their homes. If you have a severe problem with snow accumulation, it is best to call a professional.

If you notice the following signs of roof failure in your home, consult a professional immediately:

  • Cracks in the walls.
  • Doors that pop open.
  • Doors or windows that are difficult to open.
  • Creaking, cracking or popping sounds.
  • For commercial or industrial buildings:
    • Sprinkler heads pushed below ceiling tiles.
    • Sagging steel roof.
    • Bowed utility pipes or conduit attached at the ceiling.

One final note: I must again emphasize the fact that this is very dangerous work! I strongly suggest hiring a professional who has the tools, skills and knowledge to do the job safely.  

How to Hire a Contractor Guide

Topics: How-To Tips, Repair and Maintenance, Roofs