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Shed foundation in very wet soil

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Jun 16, 2013, 05:08 PM
Shed foundation in very wet soil
And I do mean really wet. I can drive a 1/2 inch piece of rebar a good 30 inches into the soil by just pushing on it.

I back filled and built a shed in the location years ago. Unfortunately I did not back fill quite enough and when the rains come the shed floods. I've decided to tear down and start over.

I'm considering constructing a frame from treated 4x6's and that will raise the surface up a good foot or so. I'm thinking of filling the frame with crushed limestone and then building the shed atop the stone. One reason I think this may be the way to go is there will be nowhere for animals to live beneath the shed. If I were to pour concrete pads and build the structure on posts there would be a large gap that would give animals plenty of room to move in beneath.

I believe this plan should work, but if anyone has any experience, or theories, to the contrary I'd be interested to hear.

Jun 16, 2013, 08:04 PM
I am going back and forth on what to say about this one. On one hand, thinking of soft, wet soil I want to advise that you dig down to solid earth to make a solid foundation.

Then, the little contractor on my other shoulder says, "It's just a shed, lighten up will ya".

So it's a matter of spreading the load so that it doesn't sink into the soft soil. What about a shed-sized slab, then raise it up on piers to get above flooding and then make a solid skirt to keep the critters out?

The other way would be to do a mono-pour raised slab that will do double duty as both footers and flooring, but this will be more expensive.

For a different approach, is there any way to install drainage that will let this area dry out?