Filling gap between slabs for garage base

[sevani08]

Tore down an old corn crib and now have two 5x30 slabs with a 12-foot gap between them. I'm planning to fill that gap with a 10x30 slab to make a full 20x30 base for a garage. The old slabs have footings, question... do I need to add footings on the new section and tie it all together with rebar?

 

[m@c nchz]

do I need to add footings on the new section and tie it all together with rebar?

yes, you absolutely need footings for the new section, especially since the old ones have them.
You want everything to settle evenly under the weight of a garage. And for sure, tie it all together with rebar!
You'll want to drill into the existing slabs and epoxy in rebar dowels to connect the new pour. That'll prevent differential movement and cracking down the line. Good luck with the pour!

 

[sevani08]

yes, you absolutely need footings for the new section, especially since the old ones have them.
You want everything to settle evenly under the weight of a garage. And for sure, tie it all together with rebar!
You'll want to drill into the existing slabs and epoxy in rebar dowels to connect the new pour. That'll prevent differential movement and cracking down the line. Good luck with the pour!

Got it, thanks! I was planning to tie everything together but wasnt sure how necessary the footings were for the new part. Quick question by the way, how deep would you recommend making the footings to match the existing ones? And do you usually use #4 or #5 rebar for the dowels?

 

[SetInCement]

#4 rebar dowels should do just fine and you can epoxy them to the old slab, this is the most common approach. With that said, if you're planning on moving some weight over there, you might consider #5.