While the fasteners in a ledger-rim joist connection made according to IRC specs should be adequate to resist shear forces, lateral forces may still pull the ledger and rim board away from the house. The best practice, suggested by the 2012 IRC ( Figure R507.2.3), is to use hold-down tension hardware in at least two locations to tie deck joists to floor joists of the primary structure. The illustrations show suggested methods for bracing ledgers when the deck joists run either parallel to or perpendicular to solid-sawn or wood I-joist floor framing.
Here are some rules of thumb for sizing framing members for simple deck designs. To size framing for complex designs, or decks with long spans or multiple stories, consult your building department or an engineer.
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