Addition on floating slab

Old 03-22-11, 05:45 AM
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Addition on floating slab

Gotta put on an addition on a floating slab which will be unheated. This will be attached to a heated building on a floating slab. How do you connect the 2 buildings together yet keep them seperate? Thanks for any help you can give! Jeff
Old 03-24-11, 03:11 PM
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I would frame another wall a few inches from the existing wall & use Zmax L brackets for support. Use pressure treated wood.
Old 04-04-11, 04:03 AM
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If this is two seppert slabs from two differant pores then there will always be movement where the two join.
What I would have done is dig out all the old top soil at least 12" where the new slab was going and done a full footing down below the frost line and set concrete block until it was just below the old slab, used soild block for the top row, back leveled the middle of where the new slabs going, Compacted the area in the middle and checked level but left it deeper on the outsides, laid 6 mil. plastic with 1-1/2 thick blue foam on top of that then pored the concrete.
The outsides of the block need to be waterproofed before back filling.
That way the slab will not move and the floor would be moisture free and would stay warmer.
How far above grade is this slab you plan on building on top of? If it's at grade then water will get in under the walls and will rot out the siding, or the weed wacker is gong to tear it up.

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