Snow Load on Pergola
Snow Load on Pergola
(OP)
Is there a code provision to reduce the snow load on a lattice type structure such as a pergola? (IBC or ASCE7)
When the joist members are far enough apart, the snow only collects on the surface area of the members. Other times, however, the members are close enough together that I feel the snow could bridge across the members and collect more weight than just the exposed surface area, but less than a full roof snow load.
ASCE7 has a force coefficient for wind on lattice frameworks, but I am not finding anything for snow.
If no code provision exists, what loads have you used in past experiences?
When the joist members are far enough apart, the snow only collects on the surface area of the members. Other times, however, the members are close enough together that I feel the snow could bridge across the members and collect more weight than just the exposed surface area, but less than a full roof snow load.
ASCE7 has a force coefficient for wind on lattice frameworks, but I am not finding anything for snow.
If no code provision exists, what loads have you used in past experiences?






RE: Snow Load on Pergola
RE: Snow Load on Pergola
RE: Snow Load on Pergola
The other issue I ran into was lateral wind load. I did not want to assume that the wind would behave in a purely horizontal nature, but would attack the 2x2 slats and 2x8 joists at some angle, therefore adding to the lateral loading. I couldn't find anything about angled wind loading in ASCE 7 or IBC, but I did find a European code which required a 10 degree variance in wind attack.
RE: Snow Load on Pergola
RE: Snow Load on Pergola
Pf = 0.7(0.9)(1.2)(0.8)(30) = 18 psf