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Recessed slab question: How to pour?

John Brown | Posted in Green Building Techniques on

I am building a small 12′ x 16′ shop that will be plumbed with a wet room. The foundation will be a slab on grade with a recessed slab for the wet room. In order to achieve the recess in the slab (probably ~3″), I am wondering if it makes more sense to do 2 separate pours and/or use an expansion joint in the slab to control cracking and thermal changes. I have attached a rough rendering of what I envision the slab to look like. I’m just not sure how to best approach this recessed slab.

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  1. GBA Editor
    Martin Holladay | | #1

    My guess is that you will want to pour everything at once, with a curb form at the transition. But the person you need to ask is your concrete contractor.

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