Concrete slab for new home gym

[JO22.prj]

My brother and I are working on our parents' old place and we want to build a home gym at the lower rear part of the garage. We're thinking of removing the dirt platform, pour in a concrete slab, including some footings for the walls, to get a solid, flat floor for equipment. The base is pretty much solid rock, which I can either work with or break up with a jackhammer.

Now we need ideas on how to best work around or incorporate existing Sonotube column footings into this new slab. Should we be using a compacted gravel and moisture barrier under the slab? What's the minimum slab thickness I should consider for a home gym?

I'd appreciate getting expert advice and feedback!

 

[Green Ivy]

You'll want compacted gravel and a moisture barrier for sure, the minimum slab thickness should be 4 inches, but go 6 inches if you're adding heavy gym gear and anchor around Sonotubes carefully

 

[Scarlet12]

Where exactly are those Sonotube footings located in relation to your planned slab, are they centered under future walls or scattered? That'll affect how you tie the new concrete to the existing footings properly