How Much Snow Is Too Much On A Flat Roof

Of snow equals about 1 to 1 1 2 psf.

How much snow is too much on a flat roof.

The weight of snow depends on how much water it contains. This is the one question that you need to answer. Roof collapse can happen to new and old buildings alike and can cause extensive damage to the building and contents. 57 pounds a square foot.

Low pitched and flat roofs are most susceptible to collapses. So a risky roof is flat or slightly. That means 12 inches of snow on a flat roof creates an additional r 12 of insulation that arrives at a time of year when you most need it. The r value or resistance to heat flow for snow is about r 1 per inch.

A flat roof can be constructed to address the needs of the particular building regardless of location. Fluffy fresh snow can weigh as little as three pounds per square foot compared with 21 pounds for wet heavy snow according to fema. The snow settles on it evenly rather than being blown into large drifts which can cause a roof to fail. How much snow can your roof support.

These questions aren t quite so easy to answer because there are several variables. Most roof designs can handle snow loads of 20 40 lbs per square foot. And whenever it snows the flat roof supports an additional insulating blanket. It also helps if the roof is in a sheltered area.

As you know there is a big difference between a blizzard hitting your town and a dusting of snow. A cubic foot of water weighs about 62 pounds. How much is too much.