Flat Roofs And Snow Load

Want to find out more about snow loads around oregon.

Flat roofs and snow load.

Structural engineers association of oregon. As a result equation 7 1 which accounts for loss between events will result in a non conservative value. They help with roof snow removal and rainfall by funneling it away from your roof and siding. The snow load that is applied to our structure is not the ground snow load but in most cases the flat roof snow load.

One of them is that flat roofs leak more easily than pitched ones. Employing a combination of steel and wood on this connector roof the architects engineered the roof to support sustained snow loads while capably protecting the walkway below from snow accumulation. Another is that they cannot handle as much snow weight as pitched roofs because the snow sits directly on the roof. Check out this website.

But in flat roofed homes they re extra important. Minimum flat roof snow load values. For roofs that are flat and with ground snow loads lower than 20 pounds per square foot the roof snow load is equal to 70 of the product of the exposure thermal and importance factors and the ground snow load. Other considerations for sloped roofs can be found throughout chapter 7 of asce 7 10.

The flat usonian roofs are designed to hold 25 psf pounds per square foot of snow which is a live load meaning the snow load isn t going to be there permanently. Combined with the snow catching ability low and flat roofs are able to blend in with their natural surroundings quite seamlessly. Asce 7 05 equation 7 1 assumes that the snow load results from multiple events. Flat roof snow loads p f.

Step 4 determine the flat roof snow load. Neither of these are accurate. In regions with relatively low snow load values the load from a single event may result in the peak loading. For ground snow loads greater than 20 pounds per square foot the roof load is equal to 70 of the product of the exposure thermal and importance factors the ground snow load and 20 pounds.

There are a few common misconceptions regarding flat roofs that are stubbornly persistent.