How to Know When There is Too Much Snow on Your Roof

Lots of Snow on a Rooftop

One of the first concerns of homeowners after a heavy snowfall is whether the accumulation is large enough to threaten the structural aspects of the roof. In terms of the first line of defense, municipal building codes are generally written to cover the heaviest snow accumulations in the local area to ensure that new roofs have the structural integrity to withstand weight-bearing demands. The vagaries of weather, however, can result in events that go well beyond anything that has occurred before, which may require further assessment of the snow that is sitting on the roof as well as the roof itself. These assessments include:

  • Determining the weight of the snow – The first determination of the threat posed by a large snowfall isn’t necessarily about the depth of the accumulation, but the weight of it. For example, dry snow (aka powder) is much lighter than snow that contains high levels of moisture, meaning that the depth of an accumulation of dry snow can be over 6 times deeper than one with higher moisture content with the same load bearing weight. The easiest way to determine whether the snow on your roof is dry or wet is to examine a couple of full shovels of snow from the ground level. If you see clumps or chunky pieces on the head of your shovel, the snow contains a relatively high level of moisture. Granulated snow, on the other hand, will be much lighter and won’t stick together.
  • Checking the swing of the doors on the level of the house directly beneath the roof – One of the first signs of stress on the structure will be the bowing of the framing, which will affect the way that doors swing and close. If you notice a tighter feel when you swing the doors or difficulty in closing them, you may be seeing the first signs of too much snow on the roof.
  • Look for new cracks around doors and windows – Another sign of stress resulting from a heavy snow accumulation on the roof will be cracks in the walls around doors and windows. Cracks may occur before changes in the swing and closing of doors become evident, so pay particular attention to these signs of structural duress.

If your assessments are indicating that you have an accumulation of heavy, wet snow that is challenging your home’s structure, do not make the mistake of trying to remove it on your own, which can be extremely dangerous and may actually result in unnecessary damage to the roof and gutter system. Instead, call your local roofing professionals with details on your circumstances to facilitate a fast and safe removal of the snow on your roof.