Sloped roof reduction of load in Drifting snow
Sloped roof reduction of load in Drifting snow
(OP)
Good afternoon all,
I am working on a structure that is attached to a higher structure. The new structure will have an 8/12 slope.
We area allowed to take a reduction in the base snow load because of the slope. But to date I have not taken a reduction in the drift snow load for the slope.
The reason as I understand it for taking the reduction in base snow is that the wind and slipery surface cause a percentage of the snow to go directly to the ground (ASCE-7-98).
Is it not resonable to assume that the same thing would hold true for drifting snow?
Thank you for your input.
Ewing
I am working on a structure that is attached to a higher structure. The new structure will have an 8/12 slope.
We area allowed to take a reduction in the base snow load because of the slope. But to date I have not taken a reduction in the drift snow load for the slope.
The reason as I understand it for taking the reduction in base snow is that the wind and slipery surface cause a percentage of the snow to go directly to the ground (ASCE-7-98).
Is it not resonable to assume that the same thing would hold true for drifting snow?
Thank you for your input.
Ewing






RE: Sloped roof reduction of load in Drifting snow
RE: Sloped roof reduction of load in Drifting snow
Don't forget about impact loads when you have a higher roof and then a drop over 4 ft to a lower roof and over 70 psf snow load. The impact loads are usually 150% to 200% of the snow load and can be more critical than your drift loads. Here in Washington state I have to deal with some very high snow loads up to 300 psf in the mountain areas. We have very little drifting due to the wet snow but impact loads from one roof to another can be critical.
Good Luck