Ground snow load might seem somewhat confusing until you read the basic premise that is identified in irc section r301 6 which states.
Live load wood lattice roof.
Since it is possible to use the attic for storage the live load of the attic floor is set at 20 psf according to code.
The roof shall be designed for the live load indicated in table r301 6 or the snow load indicated.
What happens if you put 20 psf or 300 on the joists only not the purlins.
Minimum design loads for buildings and other structures location uniform load psf.
This issue of live load vs.
Unlike the trussed roof live load and dead load of the rafters and ceiling joists must be accounted for as separate systems.
0 9d 1 0w a load factor of 1 6 when adding to load 7.
Electrical tower you could expect maintenance live load of 300 lb on the horizontal elemental.
As a result the live load dead load and distribution of forces are different.
0 9d 1 0e effect or 0 9 when resisting the load when permanent.
If you had a 40 ft tall open lattice structure i e.
Minimum uniformly distributed live loads adapted from sei asce 7 10.
In the end i think this all boils down to good rationale ca notes and your local building code.
1 2d 1 0e l 0 2s when h loads are present they shall have 6.
For any species the allowable span generally increases as the joist or beam increases in size.
Victor staley a building official in the town of brewster mass responds.