# Climbing frame, help with joist sizes



## Wayne17 (15 Apr 2020)

Hi all
I am planning to build a climbing frame in the garden for the grand kids. Just wondered if my choice of joist sizes seem correct? I plan on building a 2400 mm x 2400 mm play tower, using four 150 x150 posts 3.6 meter concreted 600mm into ground. Have a decked platform 1500mm high with 200 x 50 joists and rafters 400mm spacing ,where the slide, monkey bars and climbing wall will be. Then have a apex roof with a 600mm rise , 100x50 rafters 400mm spacing . Roof will be cedar shingles on 38x25 battens. Does this all sound ok?
Thanks
Wayne


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## MikeG. (15 Apr 2020)

The timber sizes are OK, although the 4x2s only span just under 2m if used in a floor. As this will only be taking the weight of kids, without furniture and so on, then they'll be fine. It's the junction with the ground where this will fail. If you could raise the bottom end of the posts off the ground with some steel then this will last more than 3 or 4 years.


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## Wayne17 (15 Apr 2020)

Hi 
Thanks for your reply. The 4x2 will only be used for roof , will be using 8x2 for decking floor. Had thought about some steel post supports , but I thought it would be more sturdy if the posts were concreted into the ground?


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## MikeG. (15 Apr 2020)

Sturdy for 2 or 3 years before they rot off at the top of the concrete. It's absolutely inevitable that this is where they will fail. The best solution is a steel plate with a foot on it and some big holes, cast into the concrete sticking up 18 inches or so, and sitting in a slot in the foot of the posts, bolted. The post feet should ideally finish about 6 inches from the ground.

Those joists for the floor only need be 145x45. 195 is completely unnecessary.


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## Wayne17 (15 Apr 2020)

Ok, thanks for you advice. Will look into the post brackets


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## Shultzy (2 May 2020)

I would use "Concrete Godfather Support Posts" concreted into the ground, then bolt the wooden posts to them. Cover the exposed concrete in thin timber with rounded corners to protect the children. Easy to replace.


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