OT: self-leveling floors

[Tony]

I've been putting up for way too long with a concrete floor in the
shop that just keeps generating dust. its become intolerable. I've
already moved 1/2 the shop into the other half and plan to get started
asap.

thing is, am not sure which way to go.

I'm considering using a self-leveling epoxy/cement/god-knows-what
called Mapei Ultraplan 1

http://www.mapei.it/referenze/Multimedia/Ultraplan1_TD_EA.pdf

technically its not a finished floor -- its meant to be a level foundation
for carpet / wood / tile -- but I'm wondering if this isn't a marketing gimmick?

its rated to 4500 psi after 28 days.

thats concrete to me.

has anyone ever tried anything similar?

I've considered sealants and paints but i think this concrete just stinks
and will break easy if i drop a heavy hammer for example. by break i mean
easily pulverize into powder.

Tony

[Evan]

"its rated to 4500 psi after 28 days."

Is that how long it takes to harden completely? Sounds like it might stink for a very long time. I would try to find somebody that has actually used it to ask about the product.

[SGW]

It sounds like quite a job to put it on. Whether it would stand up to use and not flake off, who knows. If you made it 1/2" thick, I would think that would be pretty durable. BUT, surface prep is everything, and you would certainly want to take the time to do the surface prep correctly. The data sheet talks about sandblasting or shotpeening the concrete and priming with a special primer prior to installation of the coating. At the very least I think I would brush thoroughly with a stiff-bristle brush, vacuum well, and use the special primer.

Have you thought of using some kind of floor covering like asphalt tile? Out of sight, out of mind...

Or put down a vapor barrier and install a hardwood floor.

[uncle pete]

Is your current floor level? Or are you thinking of buying this product to both level and seal the concrete? Generally products like this get really expensive once a large volume is needed. If your concrete is ok for level then they make lots of different interlocking tiles in a variety of materials and made specificlly for aplications like this. These aren't exactly cheap either but they are one more option.

Pete

[SGW]

Pete has an interesting idea: that interlocking floor mat like this: http://www.dri-dek.com/
It would cost you something to cover an entire floor with the stuff, but you would end up with a floor more comfortable to stand and work on than concrete. You would probably want to apply some kind of sealer to the concrete first, but the mat would then protect it from abrasion so it would stay put and not wear off.

[john b]

If your concrete is level you can probably get by with a concrete densifier. Quick and easy to apply. john b

[Tony]

all in all i'm looking at about 700 square feet. a little more than half of
that is shop space so i'll be dropping things and rolling heavy stuff.

Evan, spec sheet says something like 1000 psi in 3-4 hours full cure 4500 in
28 days. its supposed to not shrink.

i'm afraid anything like a sealant or paint will simply flake off with time as
I drop things, etc. i often move my heavy workbench out from way from
the wall for larger projects. that gets dragged pretty hard.

but no forklifts.

yes the floor is reasonably level.. the concrete is finished more like a new
sidewalk than a smooth floor. wooden float? i dont think it was brushed.

anyway i can see the smoothed over small aggregate at the top as the
concrete has been wearing away.

and yes, for the self-leveling stuff i'm looking at spending about $1k to put
down 1/4" thick.

[Chris S.]

Yes, I realize that a wood floor introduces issues with keeping machines leveled but if I ever get the energy up to do it that's the way I'm going. I don't give a damn if its CDX plywood or yellow pine tongue & groove planking, there's nothing more painful than seeing your hard work or ground steel tooling heading toward concrete via gravity feed.

[Scottike]

I may be wrong here, but it sounds like your slab froze in the first 48 hrs or so after it was poured.
That will cause the "finish" layer on top to crack, chip, and basically peel away from the underlying slab, which may still be good - depending on how hard the freeze was.
The only real solution would be to scarify the surface down to good concrete and then apply a finish material (epoxy, leveling cement, etc.) that could be applied thick enough to bring the floor level back.
If you just apply a finish/sealer coat of something on top, it's still relying on the weak "finish layer" for the bond to the underlying slab, which you already know is giving way.
That being said, just an epoxy sealer or floor paint would go a long ways towards minimizing the problem, but would probably have to be touched up from time to time, which may be more difficult to do with some of the other solutions you've been considering/presented.

[uncle pete]

Simple, Fairly cheap, Fast And easy? A 3/4" layer of G1S plwood. Easy on dropped tools and your feet.

Pete

[Tony]

Scott,
Thats very likely.. I wasn't around when they poured this floor, my old man
did quite a few years ago.. but I think one of three things happened:

1. It froze, like you said. This garage didn't have doors on it till I put them in.
2. They did it in the summer, poured the whole 700 ft.. and it was drying too
fast to finish in time so they wet it. Ie killing the finish layer.
3. they just got a bad mix.

[rohart]

I used a self-levelling compound - I think it had some acrylic in it - on a small 10x10 cellar room that had a 2 inch dip in the middle.

I didn't use enough. I think that if I'd poured enough to give me a 1 inch depth at the edges, I would have been pleased. The compound, while being of a fairly fine aggregate itself, clumped at the edges, so where the thickness of the compound tapered off it seemed to become lumpy.

If I did a similar job again, I would not plan to for a thickness of less than 1 inch. I think Scotike's analysis seems good.

The thing I like about the interlocking tiles is you can rip them up if it's no good. You lose cash, not your floor. If you like it, pull 'em up and stick 'em down again, one by one.

[Chris S.]

Simple, Fairly cheap, Fast And easy? A 3/4" layer of G1S plwood. Easy on dropped tools and your feet.

Pete

Now there's a thought. It's even cheaper than CDX. Then there's that stuff in my storage shed. The floor is some kind of rugged pressboard.

I wonder, is there a pressure treated grade of plywoods?

[tlfamm]

You might find more ideas in this thread:

http://bbs.homeshopmachinist.net/showthread.php?t=44180

[boslab]

self levellers are the way to go! you wont look back.
what they dont tell you is you can add pigment to the screed to get a coloured cement layer, so you can have green or pink or whatever, very handy buff is nice
its not that difficult to hand screed a floor, level with a nice long ali darby, just build little molehills in a grid and 6' level, let them go off a bit, pour the screed on the floor and level with the darby, not difficult. a bit of pva helps, there are plenty of floor sealers available too
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