I am constructing a 12 x 14 addition with a crawl space
The foundation will be CMUs with brick veneer. The 10 inch joists will span 12 ft and will support a master bath and walk-in closet. My foundation sub states that interior piers are not necessary on clay soil. I feel it requires 2 interior piers with a doubled 2×12 beam to break the load in the middle of the span for structural integrity. Who is right?
Also, this same sub claims that 2 rim beams on the exterior of deck posts (1 on each side of the posts) supports the joist and floor load as well as the two beams joined as doubled with glue and fasteners and attached to the top of the posts instead of bolted and nailed to the two sides of the posts. Structurally which is better and which meets code? Thank you. Jim
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Replies
James,
I score this one each.
2"x10"@16"oc will span 12'-0". The type of soil has no bearing on the spans of the wood structure above.
The IRC doesn't allow beams to be attached to posts using bolts. If you want to split the plies of the beam by having them attached to the side they would have to be let in. Both are inferior to a built-up beam bearing on top of the post.
Here is a link to the requirements for decks:
http://www.awc.org/pdf/codes-standards/publications/dca/AWC-DCA62009-DeckGuide-1007.pdf