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File description: Cleaning and paint concrete shop floors Your name: (optional) Lee M. Daniels
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Painting your garage floor is like painting your car. You get out of it what you put into it. No preparation, quickie job = poor results. But spend the time to do it right and you'll love it.
I was lucky. Four years ago we had just moved into a brand-new house with new white concrete on the garage floor, so my prep job was not the real gorilla it could have been with an old, dirty, oil-soaked floor. But I did the careful prep anyway. I had always wanted to do it, and here was an ideal situation for it.
Just as in painting your car, the secret is in the condition of the surface before the paint goes on. Cleanliness! Even though the floor was relatively new, several weeks of my cars and the builder's various vehicles had already made their marks on the virgin concrete, so the first order was to get the oil stains off. As I have written here previously, the very best way to do this is with a bag of kitty litter---the kind you can get at Wal-Mart for $1.98 works just fine. You can also buy 50-lb sacks of the same material, usually called something like "Oil-dry" or the like, at auto parts stores for $4 or $5. Pour liberal amounts of the kitty litter on each stain, and then spend several minutes grinding the pellets into a powder with a hand-sized block of wood (I use a 2x4x4). The grinding action gets the powder down into the pores of the concrete, where the stuff soaks up the oil/grease/grunge very effectively. Then you can sweep or vacuum up the dust, and you should have a nice white spot where there was once oil.
Once you are satisfied with the cleanliness of the floor, it's time to do the etching. You'll need a diluted solution of muriatic acid (HCl
solution). You can get the acid at a pool supply, hardware store, or
chemical/cleaner supplier. Mix one part of the acid with 10 parts water in a plastic bucket, then pour and spread the solution all over the floor. Spread it quickly, because the reaction is fast and you want to be sure that you get unreacted HCl over the whole surface. In other words, once the solution hits one spot on the floor, most of the acid in that puddle of solution with react before you can spread it somewhere else. You'll know that it's working. But don't do this in a closed garage - the fumes evolved are noxious! You'll see lots of bubbles and hear a lot hissing as the reaction goes.
Once you've covered the floor with the acid, you can rinse it off with pure water within just a few minutes. After it's perfectly dry, you'll want to sweep it completely. And then again. And probably another time. You'll notice that you're sweeping up a lot of concrete "dust" created by the etching process. And, just like a car, you want the surface .. (all together now)... CLEAN! You will now have a clean, grease-free, "roughened" surface that will hold your paint very well.
The very best, but also most expensive, way to go is with a 2-part epoxy. I went the cheaper way with a good-quality floor paint recommended by the dealer. I also bought a container of sandy stuff that you mix with floor paint to give it more texture so that it's not so slippery. A painted concrete floor can be *really* slippery, especially with a little water on it. If you have a spouse, friend, kids, etc. who will be walking through your garage, you definitely want to add the texturizer. I don't know the best way to apply the epoxy, but the floor paint went on very well with a roller. I just had to keep stirring up the paint in the roller pan to keep the texturizer suspended. I did two coats, and the results were great.
Four years later I'm still glad I did it. Anything that spills on the
floor wipes right up without leaving a stain. Sweeping the garage is a
*lot* easier; dirt just doesn't stick. There is one small spot where a few bits of paint have flaked up, right under one of the car tires, but that's no problem compared to the ease of taking care of the rest of the floor. If I ever move to another garage (with a house attached), guess what I'll do before unpacking my tools?