I have a 8x16 foot deck should i add cross braces to it?
If you are only using those deck blocks to support the deck and have nothing actually anchored into the ground, then cross bracing the corners will help tone down some of the wiggle you'll get. Other things that you didn't ask but:
1. Your support really needs to be at the outer perimeter, especially for such a small deck. There is no reason to have such a cantilever that close to the ground. With an only 8' wide deck it would be possible to tip it if enough people stood on the edge.
2. It looks like your joists are set about 36" on center. Too much distance. 24" OC is max, even for 2x6 decking. 16" OC is much better. You really need to add a joist in-between each joist that is already there.
Thanks, i was going to brace the corners so good to get the second on that, joists are on 30 inches off center with a couple at about 28.
I will see what i can do to support the outer perimeter,
in the mean time any suggestions?
Just repeating the above, especially the need to double up on the number of joists. If you don't, it's going to be a bouncy deck to walk on.
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