Rasing end of slab

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Blue Jay

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I have a hot tub sitting on a slab (5" thick) 7' X 8' the one end of the slab is hanging over the backfill of the foundation wall about 20" and the slab is tilting about 1.5" low on that end, no cracks in the slab. What would be the best way of raising this back up?
 

Jeff Handy

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Tub might need to temporarily come off the slab during the jacking process.

To provide access to drill the slab to inject under it.
 

bud16415

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My hot tub full is over 6000 pounds and empty about 800. I would at least drain it if I was going to try any DIY jacking. That’s a thick slab and if it has any rebar in it maybe you could dig under the low end put a beam across and a couple big jacks and lift it and then pour some concrete under the void to hold it.


Before I did that I would call around and get prices on mud jacking but I have an idea they might be pricey.


If it were mine and I felt it had stopped dropping I would slide the tub off and build a PT wood deck above the pad and resting on the pad with the taper I wanted. It would raise the tub a couple inches but I have always liked knowing there was air circulation under the tub and a place for water to run off. Some tubs have an ABS base pan on the bottom and some don’t. Another method DIY friendly would be to add another thin pour to the top surface to get it back level.
 

Blue Jay

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I have a hot tub sitting on a slab (5" thick) 7' X 8' the one end of the slab is hanging over the backfill of the foundation wall about 20" and the slab is tilting about 1.5" low on that end, no cracks in the slab. What would be the best way of raising this back up?
When I get to feeling better (have to work in a crawl space) I will try to get pictures. Plenty of room for air under as I have a hoist under it to raise it up to work on, it is a sunken tub I just step in same level as the floor. Yes I will drain it before any lifting.
 
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