Flat Roofs And Snow Load

Asce 7 05 equation 7 1 assumes that the snow load results from multiple events.

Flat roofs and snow load.

The easiest way is to push a yardstick into the snow on the roof selecting an area that looks typical of the overall snow depth. Flat roofs can t possibly support all the extra weight a totally valid concern but rest assured your architect and engineer have this in mind when designing the roof structure. Snow is actually one of the easiest to design for and all. There are a few common misconceptions regarding flat roofs that are stubbornly persistent.

Other considerations for sloped roofs can be found throughout chapter 7 of asce 7 10. In regions with relatively low snow load values the load from a single event may result in the peak loading. In our case let s assume that our structure has a flat roof roof slope 5. For example 18 inches would be 1 5 feet.

Wind seismic building weight furniture occupants etc. Certainly the weight of snow can add up but your home must support a variety of loads. First figure out how deep the snow is piled up there. One of them is that flat roofs leak more easily than pitched ones.

You need to use a snow load formula for flat roofs. As a result equation 7 1 which accounts for loss between events will result in a non conservative value. The flat roof snow load is calculated using formula 7 3 1. Minimum flat roof snow load values.

Another is that they cannot handle as much snow weight as pitched roofs because the snow sits directly on the roof.