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Breakin' Stuff
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Discussion Starter · #1 ·
Hey all, I'm putting plans together to build a deck out back of my house. I plan to do a floating design. The struggle I'm having is how to support it because there is an existing patio. It's constructed with a 6" concrete slab (yes, 6") with brick on top, grouted in. My thought is to use deck blocks on top of the concrete, and buried concrete piers where it extended over the yard. Any thoughts on this design?

 

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retired framer
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Thanks for the comments! What do you mean by 2x4 blocks? Like this?
Yes, but the only have to be 2x4 the deck above holds the top straight

You only need one row in a 14 ft span but I would go 2 rows just because.



13 feet should be okay with 2x10s the cantilevers don't count.

9 ft for double 2x10 beams should be good.
 

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Hammered Thumb
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Yes, but the only have to be 2x4 the deck above holds the top straight

9 ft for double 2x10 beams should be good.
That (2) 2x10 outer beam where joists above span 13' is only good for about a 6'-8" beam span.

I think the changes you made were trying to eliminate multiple posts on the slab so when it settles you'll have uniform movement/or can shim later as necessary? Also, putting the flat 2x4 blocking at the bottom edge allows lots of water to sit on them?
 

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retired framer
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That (2) 2x10 outer beam where joists above span 13' is only good for about a 6'-8" beam span.

I think the changes you made were trying to eliminate multiple posts on the slab so when it settles you'll have uniform movement/or can shim later as necessary? Also, putting the flat 2x4 blocking at the bottom edge allows lots of water to sit on them?
Flush not flat. :wink2:
We do 2 ply 10 and 12 ft all the time but he could go to 3 ply or move up to 2x12.
 

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You are in Cleveland (so am I) where structures are subject to frost heave. Either make all of the footings to frost depth, or don't make any of them to frost depth. If you mix floating footings with frost footings, the deck will move and lean during the winter, and nails will pull and straps may tear.
I would pour tiny 12" x 12" x 6" thick concrete patios at the outboard end of the deck, and then rest deck blocks on them. Then the entire deck will move uniformly with frost heave, and all will be good.
 
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Breakin' Stuff
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Discussion Starter · #14 ·
You are in Cleveland (so am I) where structures are subject to frost heave. Either make all of the footings to frost depth, or don't make any of them to frost depth. If you mix floating footings with frost footings, the deck will move and lean during the winter, and nails will pull and straps may tear.
I would pour tiny 12" x 12" x 6" thick concrete patios at the outboard end of the deck, and then rest deck blocks on them. Then the entire deck will move uniformly with frost heave, and all will be good.
Yeah, that's probably a good idea. It seems weird having two different types of supports.
 
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