Structures Subject to Vertical Loads
Load path
1. sheathing
2. small beams
- most-closely-spaced members
- rafters, joists, subpurlins
- e.g. 2 foot OC
3. medium beams
- beams, joists, purlins
- e.g. 8 foot OC
4. large beams
- girders
- e.g. 18 to 40 foot OC
5. columns or bearing walls
For live loads, use tributary area of member being designed instead of loads from smaller members.