This is probably a common question, but trying to sort it out has my head spinning....
I'm trying to work out the size of a post and beam foundation for a 10x10 shed I plan to use as a workshop. Shed will have 2x6 floor joists, 2x4 wall construction.
What I think I know:
I need 3 beams, as a 2x6 has a max span of +/-8ft. Three beams will also deal with any flexing issues in the 2x6 floor joists. Posts will be set 48" deep (yay, Canadian frost line!).
What I'd like to do:
Sink 2 rows of 3 posts each to support a double 2x8 beam, with posts set 8ft apart, creating a 1 ft cantilever on each end of each beam. Outside beams will be set 1ft inside the 10x10 shed perimeter to facilitate skirting foundation.
Here's a crappy pic of the foundation plan.
Is a double 2x8 beam sufficient or should I upsize to triple 2x8 or double 2x10s?
4x4 posts or 6x6 posts?
The roof ridge runs parallel to the beams. Should the outside beams be directly under the bearing walls or is the small offset ok?
Thanks in advance.