Removing paint from interior concrete floor

[Jack Olsen]

I have a friend doing this, and he asked for some advice after dulling a scraper of some sort. I guessed that a wire wheel on a 9" grinder might do it cheaply. A quick google search shows some pricey soy-based thinners that reportedly destroy fewer brain cells than ordinary Jasco.

Has anyone who's done this give me some advice to pass along? It's an interior loft-type place with a lot of layers of dirty paint on it. He got through the bathroom okay, but now the big main space is kicking his ****.

(I'm looking to avoid going over there to do it for him, if I can help it.)

 

[Stuart in MN]

Sounds like the sort of job where I'd hire someone with a shot blaster.

 

[Jack Olsen]

Thanks. But he doesn't want to scar the surface. As I understand it (which isn't much), I think shot blasting would take too much away.

 

[STClurker]

pressure washer?

 

[Bootybug]

I rented a floor buffer/sander with massive sandpaper. It took it up pretty good and left a great finish. Be sure and use a good dust mask, not those cheesie surgical masks, but something with filters.

 

[DGC15]

I did my garage floor. I got the strongest paint stripper the lumberyard had. Took about 5 gals to do a 24 X 26 floor. Put it down in a small area, wait 5 minutes and scape it off with a putty knife. Worked out real well. After I got it off, I washed it down with a pressure washer and then mopped it with TSP soap.

 

[MrMark]

I would use stripper and ventilate well. Keep scraping my friend.

 

[Kevin54]

The rental places rent a floor sander that has a plate with carbide inserts for stripping paint and glue. The local Sun Rental has one for $75/day. I need to rent one to do the same thing to my garage and was looking at them. They say the carbide won't do damage to the concrete, so I don't know if it will scratch it up or make it look smooth

 

[djjsr]

I've been using some "safe" stripper from 3M. It doesn't have quite the power of the stronger chemical strippers but it works and doesn't kill your brain cells.

It's water soluble and it seems to dry out too quickly, so after I apply it using a 4" brush, I spray a fine water mist on it with a pump sprayer, cover it with a cheap disposable plastic dropcloth to keep it wet and let it sit overnight. The next day, I peel off the plastic and throw it away. Spray a little more water on it and start scraping. Works pretty good.

I have about 1400 sq ft that needs stripping so I've been doing a small section at a a time when I'm in the mood (about 10' x 10'). I quickly realized that my knees didn't like what I was doing, so I bolted a scraper to a long handle so I can scrape the floor standing up.

 

[MoonRise]

In the past I have also used the 3M 'safer stripper'.

Definitely not as fast as the 'nasty' MEK-based ones, but worked just fine. Follow the directions and apply a nice thick coat and then cover with plastic wrap (or plastic sheet for a big area like a floor). Leave overnight or so and come back later (the next day IIRC) and scrape all the glop (remover + now-softened paint) off. You have to wash it all off with water when done IIRC.

I think there are three main ways to strip paint: chemical, mechanical (grinding, scraping, pressure washer or other pressure-assisted media), or thermal (heat gun). Pick the desired approach and have him go at it.

 

[Jack Olsen]

Thanks, guys. I'm going to go and have a look at his floor. Now I know the options.

 

[soo_smitty]

If there's someone local might be interesting to either get a quote on Dry Ice blasting or see what's involved in renting the stuff necessary. Never done it personally, but it looks like it works good

 

[csp]

Dry ice is what I was going to suggest also. It's used a lot in mold remediation in homes (like attics) as it doesn't destroy the base material.