Snow Load On Sloped Roof

A great deal of confusion currently exists among engineers architects recreation specialists and maintenance personnel concerning the proper snow loading to use for the design and maintenance of trail bridges building roofs and other structures in mountainous high snow load areas.

Snow load on sloped roof.

Sloped roof snow. Once you know these values our snow load calculator automatically finds the total weight of snow on your roof. The snow load that is applied to our structure is not the ground snow load but in most. Flat roof snow loads p f.

Snow load thickness density. Calculating roof snow loads w asce 7 10 a walk through on how to calculate roof snow loads per asce 7 10. The effect of snow loads on a structure can have dire. Ground snow load value.

It makes sense when designing a metal roof to shed snow not to keep it on. You can also find the load per square meter or square foot of roofing by opening the advanced mode. If you want to calculate these values by hand use the following formulas. P s c s p f.

To do this i use conservative too heavy dead loads and full snow loads regardless of pitch. On multiple factors including. It is critical that a designer specify enough snow retention devices based on the slope and snow load. Snow loads acting on a sloping surface shall be assumed to act on the horizontal projection of that surface.

However in my practice i typically use the horizontal run of the roof for both types of load. Boca also allows you to reduce the snow load for roofs with slopes greater than 30 degrees presumably because snow will slide or blow off steeply pitched roofs. 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. It is determined based.

For dead loads you are correct. Discount that actual snow loads may exceed them only that the risk of snow load induced failure is reduced to an acceptably low level. With expansion and contraction of the metal it is difficult to attach snow retention devices into the roof decking without causing a roof leak or slotting of the metal panel from the snow bracket fastener. The thermal factor c t from table e 3 determines if a roof is cold or warm slippery surface values shall be used only where the roof s surface is unobstructed and sufficient space is available below.

Technically you should use the actual rafter length when adding up the weight of roofing materials. Roof snow load is defined as the weight of snow on the roof surface used in design of the building structure ibc 2012. For locations where 0 pg 20 psf all roofs with a slope w 50 with w in ft shall have a 5 psf rain on snow surcharge. To figure out the load on your roof take the depth of snow in feet and multiply it by the weight of a cubic foot of snow.

This rain on snow augmented design load applies only to the balanced load case and need not be used in combination with drift sliding unbalanced or partial loads.