How much snow accumulation can a home’s roof handle in Missouri?

Heavy snow on rooftop

The recent snowstorm brought us over six inches of new snow in the Lee’s Summit, Missouri area as well as most of Missouri.  That snow is very pretty, but it brings in a lot of questions about snow and ice and their impacts on trees, houses, buildings, and especially your roof.  How much snow is too much accumulation on your roof?  Can you wait for the snow to melt or do you need to actually remove it yourself or get a professional? Read on for some basic advice about snow accumulation on the roof of your house.

It’s important to know when referring to snow accumulation what type of snow or accumulation there is.  All snow is not created equal.  Packed snow weighs a lot more than new snow, and ice weighs far more than both.  So if you experience a second snowstorm before old snow has had a chance to melt, the packed snow now topped with new snow accumulation could be more than your roof can handle.  And that’s not even counting if you experienced ice on your roof and haven’t had weather warm enough to melt it.

The general rule from the Insurance Institute for Business & Home Safety to prevent roof collapse  is that a house should be able to support 20 pounds per square foot of roof space.  Twelve inches of snow is roughly 5 pounds per square foot so your roof should be able to support up to 4 feet. Packed snow of 3 to 5 inches equals about 5 pounds per square feet, so 2 feet of old snow could be too much for a roof, and ice equals 1 foot of fresh snow.   Some areas that tend to receive abundant snowfall yearly may have higher loads mandated by your local building department.  You can call them to find out what the regulations were at the time your house was built.

The best thing to do to put your mind at ease if you can’t tell if your roof can handle the snow accumulation is to safely remove it.  For an easily accessible roof, a snow rake can be the right answer.  If you have a dangerous, steep or roof in disrepair, or are simply worried, call a roofing professional to discuss. Your local Missouri roofing contractor will have the right answer for your individual home and area.

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