DIY Elevated Play fort -- plan and support questions

A play fort – awesome!

I do not believe you need intermediate supports on a 10’x10’ deck, but you can find many resources for span tables for various framing lumber dimensions. You are essentially building a stand-alone deck. You may have options between using larger joists and 4 posts, or smaller joists and 8 posts. The span ratings for cedar joists may not be the same as those for PT pine, so be aware of that.

As for footing depth, check you local building code for decks, and follow it. You can’t go wrong.

when i built my daughters two story club house which is around 12’ if memory serves i used 6-4×4’s concreted 24” in the ground.i put cross braces at each corner and doubled the floor joists.it doesn’t sway any and me and a friend was on the top floor building rails which we both are fairly large and we couldn’t get it to sway and held us just fine.the way i look at it it’s for my daughter and if its overkill to add 2 more post i’m fine with it.hope this helps.welcome to lumberjocks.

-- It don't have to be straight,it's just a suggestion!!!

This job has never moved. The outside corners are PT 2×4’s butted together to make an L shape, then all the bracing/rails/floor joists are bolted or screwed to the inside of the L
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