Snowy Roof: How Much Snow Is Too Much?
In the New York City area, we are used to extreme weather conditions come wintertime, such as heavy snowstorms or Nor’easters. In general, if a home is built to meet the standards of its local building code, the roof should be able to withstand any amount of snow, especially for that specific geographic location. However, after a heavy snowfall or several consecutive snowstorms, homeowners may be understandably concerned about the safety of their families and property with a snowy roof. Read on as we explain the dynamic factors that contribute to how much snow on your roof is safe.
Consider The Slope
An important part of your roof that contributes to its capacity to hold snow is its slope. Steep and smooth roofs allow snow to slide off more easily. On the other hand, ice and snow tend to accumulate on flat roofs or roofs that are less sloped. Roofs that are somewhat sheltered have a higher chance of snow accumulating evenly, whereas roofs exposed to winds and drifts are more vulnerable to uneven accumulation. Furthermore, roofs that stand adjacent to a taller, steeper one are at risk of a load of snow sliding down.
Check Your Attic
A standard residential roof should be able to support 20 pounds per square foot of snow before it becomes stressed. Because fresh snow, packed snow, and ice all weigh differently, we do not recommend poring over your calculator trying to figure out the math.
Instead, you can look within your house for red flags. First, simply head up to your attic to examine your rafters. Look for noticeable bends or cracks. Then, in the upper floors and middle of the house, look for new cracks in the drywall or plaster, especially around interior door frames. Doors that suddenly become difficult to open or close are a sign that the frame of your house has shifted due to a structural problem. If you see any of these signs, do not panic. Simply call a licensed professional to come take a look before you end up with a heavily snowy roof that causes problems.
Snowy Roof: Preventative Steps
Many homeowners wish to clear snow from their roofs to relieve stress on the structure of their homes. However, climbing up on a roof is dangerous in any weather, especially snowy and icy conditions. For your safety, we recommend that you reach out to a professional company to help you. If you have a one-story home with a roof that is accessible from the ground, feel free to use a roof rake. When raking your roof, however, keep in mind that your goal is not to remove all snow and ice. Vigorous raking can cause damage to your shingles, which can eventually lead to leaks and further structural damage. According to a 2013 FEMA Snow Load Safety Guide, at least two inches of snow should be left on the roof after raking.
In general, a structurally sound residential home is not at risk for a roof collapse and you should not find yourself in immediate danger. However, if you have noticed any of the warning signs above, make it a priority to contact a licensed structural engineer or a roofing professional, like Greene Roofing, to evaluate your roof and home.