Enlarging concrete pad for a shed
harpoharpo
| Posted in Construction Techniques on
I had a 12′ wide x 14′ long 4″ pad poured for a shed two years ago, and now it’s time to build. Problem is, I’ve decided that I need to go a bit longer to make it a 12′ x 20′. My thought is to add two 12′ x 3′ “ears” at either end of the existing pad, but I’m not sure how to attach them so I’ve got a stable base to build on. I’m thinking that I need to bridge the joint with rebar partially set into the existing pad? If so, how deep to set the rebar, what size, what spacing, how to finish the joint…? If not rebar, then alternatives?
TIA,
Greg
Replies
Main thing is that you need to get the new base (stuff under the concrete) prepped just like the existing, and well compacted. You just need enough rebar to keep the ends from wandering off with frost heaving -- you should have even pressure from the shed all around so they don't rise or fall more than the rest.
Don't bother trying to make the joints invisible.
Enlarging slab for bigger shed
If it were my problem I would much prefer to surround the existing slab with a new foundation - creating a virtual ring beam.
Some locator dowells would be advisable to 'borrow' some benefit from the older slab, but a new cage of reinforcement would
ensure that it all stayed monolithic where it matters.
Lapun.
For a shed it does not much matter, there is negligible loads on the slab however you extend it. Do whatever is easiest for yu for a shed.
Have you considered just leaving part dirt or gravel floor?
I have one 32 ft by 20 ft shed that is all dirt floor, only thing on the ground are six pieces 2 ft by 2 ft sections of old car or truck chassis with 4x4s bolted to them.