Larssen wrote:
Why would you want a deck to be flexible
You don't, really. Movement makes people nervous, and enough movement over time might work out your screws.
Red is the ledger board, it attaches the structure to the house. Joists are held in joist hangers, which prevent twisting.
Green is the rim joist. Joists are also held here with joist hangers.
The cyan in the middle is the blocking. The blocking prevents the joists, the boards stood up on edge running away from the house from twisting. Generally, especially on long runs, you want the blocking to act like a second rim joist. Ideally, they'd look like ------- going down the middle rather than _-_-_-_- but it's difficult to securely fasten them in a line. Offsetting by a few inches doesn't make much difference. In my case, I have a chamfered corner in the foreground, and diagonal beam holding up the joists in the background. It's a more complex framing plan that makes the blocking asymmetrical, but it's plenty strong.
Last edited by Jay (2020-05-09 03:32:44)