The Pounds Of Snow On Your Roof May Literally Weigh Tons

January 23, 2015, by Ken Jorgustin

snow-weight-on-roof

You might be very surprised to discover how much snow weighs up on your roof, and the stress and potential danger your home or building might be to roof collapse after heavy accumulation…


 
A cubic foot of snow can weigh about 7 pounds if it’s dry and fluffy, and it could weigh over 20 pounds if it’s wet and compacted!

Two feet of snow over a roof with a footprint of say, 28×40 feet, could weigh 45,000 pounds! That’s more than 22 tons!

Even just one foot of the light fluffy snow will still weigh 3 tons on that same roof!

Flat roofs are especially vulnerable to roof collapse while pitched roofs can also accumulate snow.

In addition to roof integrity, watch out for snow slides off of a roof – just like an avalanche. If you’re in the wrong place at the wrong time, you could be seriously injured if caught underneath an ‘avalanche’ of snow sliding off your roof.

 
Here are a few examples of the potential weight of snow on a roof:

28×40, Light, Fluffy Snow
1 foot of snow on the roof (7,000 pounds)
2 feet of snow on the roof (13,000 pounds)
3 feet of snow on the roof (20,000 pounds)

28×40, Heavy Wet Snow
1 foot of snow on the roof (22,000 pounds)
2 feet of snow on the roof (45,000 pounds)
3 feet of snow on the roof (67,000 pounds)

 
Now imaging an industrial type building, or a barn, etc.!

Lets say the footprint is 40×60 with 2 feet of heavy snow. That roof (if it’s still standing) will be straining under 70 tons of snow.

If you live in a region where you might occasionally face a very heavy snowfall (or series of heavy snowstorms) which may accumulate deeply on your roof, you might consider having it removed! You might not be safe while living underneath all that snow…

 
Have any of you ever experienced problems with literally ‘tons’ of snow on your roof?