Snow Load Design For Roof Overhang

The snow load calculations provided by this online tool are for educational and illustrative purposes only.

Snow load design for roof overhang.

The balanced snow load is applied everywhere where the roof structure is located. When snow slides off a sloped roof onto a lower roof the design snow load on the lower roof due to sliding snow is determined using section 7 9. It goes without saying that in a warmer climate the snow load probably would be less so you need to check your code book for live loads and dead loads in your region. Partial unbalanced and drift loading.

For a porch roof the beam needs to be sized according to the maximum snow loads in your area and you must know enough about the porch design to determine how the load will be distributed and over what distance the beam will carry the load. In some cases roof snow melt systems or heat tape can be used to combat ice accumulation on eaves and in valleys. The ground snow load map shown below was scanned from the asce 7 10 figure 7 1. Sliding load on adjacent roof ponding faq s 3 minimum roof snow load clarification scenario roof load right after heavy snow w o wind no time for thermal no wind roof load p r p g 4 minimum roof snow load p m i s p g p g 20 psf p m 20 i s p g 20 psf the 20 psf value is our estimate of the maximum size of a single heavy snow.

Our sample homes are in an area where the snow load is 50 pounds per square foot of roof area treat snow as live load. Roof snow loads are based on the historical records for ground snow loads for a given location however the local building authority should always be consulted to determine the correct roof snow load to use for a given site and application. According to this section sliding loads shall be superimposed on the balanced snow load and need not be used in combination with drift unbalanced partial or rain on snow loads roof overhangs. The sloped roof snow load p s shall be obtained by multiplying the flat roof snow load p f by the roof slope factor c s.

Shed dormers should be considered if the design and style of the home allow. R802 10 2 and designed according to the minimum requirements of asce 7 10. In areas prone to excessive snow accumulation like schweitzer and similar. If you live in the us our snow load calculator compares the total weight on your roof with the permissible load calculated according to the standards issued by the american society of civil engineers regarding the minimum design loads for buildings and other structures asce7 16.

P s c s p f. After you obtain the roof slope factor from those sections in asce 7 10 the balanced design snow load for the sloped roof can easily be calculated using equation 7 4 1. This includes overhangs and multiple roof levels. Sloped roof snow loads calculations and regional design.

Shed dormers are easier to waterproof and shed snow better than gable dormers.