Finishing a Not perfect Bare Concrete Floor Best Practices
Looking for help on how to finish this floor mindful of preventing mold/moisture issues in the house, or the slab, silica dust, long lasting, and no lasting toxic fumes.
It’s a permanently enclosed garage that functions as an interior room with bare/not sealed concrete floors. South Florida, Climate Zone 10b/11a, calcium chloride test 3.6lbs per 1000 sq ft (in dry season/winter). Four walls not insulated, slab with no poly/moisture barrier beneath. 350 sq ft.
Previous 40+ years— carpet with rubbery underlayment. No water damage, no mold, but musty odor. Carpet removed, musty room odor still, stains on the concrete. Not slick but not so rough, and water darkens it right away.
Floor slopes down from one corner where the door is in every direction about 2″ total and theres a ridge wall to wall, its about 15″ across and slopes down 1/4″ on either. So flat except for ridge, but not level. Nothing noticeable unless you move a level around the floor.
I’ve researched sealers, stains, moisture mitigators, epoxy coatings, dimple mats, LVP (3lb vapor limit), carpet, rugs, sanding, grinding, leveling, priming, etching, muriatic acid, etc. and still can’t tell the simplest way to go about this or what products to use.
Also I’m on a budget, DIY, and not able to level the floor. I’m good with sanding, like the diamond grit one, and down to work, but cant grind. or power wash anything – the room is enclosed. Photo is as far as I’ve got with the floors.
If you’ve read this far, please, a method I can do with products i can get so this can be a functional room again would be so appreciated.
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Replies
With all of your constraints, unfortunately I don't think there is an ideal solution for you. Your best bet might be to use a rented floor grinder to even out rough spots, clean the concrete with muriatic acid, and apply a solid-color stain or epoxy finish. Rustoleum has one that I've found to be pretty durable, and the big-name paint brands all have something made for concrete. Just be aware that areas might bubble up or flake off in the near or distant future.
Thanks for replying. I can't grind, but I could rent a floor maintainer with the diamond grit (easier to handle for me and less dust), I dont need it level. would that work at least to accept the color?
Also I read some stains are breathable and work up to 5lbs MVER- would that be a better bet than epoxy? But they need to be sealed- do you recommend any opaque stains and sealants that would work well together, let this level of vapor breathe, without the future flaking and bubbling? and not toxic to use inside? or that doesnt exist?
i started looking at rustoleum stains but i cant tell how to know if they meet the above and my head is...full.
I was on a budget and had a similar scenario where I didn't want dust everywhere in my basement. I called some local epoxy guys and found someone willing to do the grinding and floor prep only. I was able to get it done for less than $2 per sq ft. They did a much better job with their professional equipment, grinders, and dust collection system than I ever could have. After that I did my own epoxy floor and saved a lot of money. My only regret was skipping out on the vapor barrier. I did have bubbling epoxy after 2 years.