Powerwashing paint off garage floor

[timelinex]

So in the next month couple months I am getting ready to epoxy my 3 car garage. I already even bought the epoxy! (epoxy-coat black)

However, my main issue is that the previous owner painted the floor. Lets get this out of the way, I KNOW that diamond grinding is the 'preferred' method. For a 100% bulletproof job with the best results, you have to diamond grind, I get it. I also know that it costs $100+ to rent a diamond grinder, $50+ for a handheld one to do edges and then 1 or 2 full days of tedious and possibly health hazard work.

I read online, that alot of people just power wash the paint off and epoxy it after with no problems. I also talked to a contractor that does the same thing and said he never has issues.

On the other hand, I have read someone on here post that power washing before laying epoxy is bad news. How much truth is there to this. I'm doing a personal house 3 car garage, that will mostly just see the tires of my car and the soles of my shoes as we go in and out. This won't be in a High abuse auto shop or a dealer showroom.

It gets to 110+ here in AZ, if I power wash it in 100 degree weather and wait a couple days to a week, should I have any issues? I prefer to hear from people that have experience with this, one way or the other, as opposed to people passing on wives tales of what they heard.

 

[LegacyIndustrial]

Time:

You are looking at a 3500-4000 PSI + machine. Anything less will likely not have enough power to remove your paint. Once fully removed you will need to acid etch at a minimum. This process will also require at least a week to dry properly.

A tried and true method would be the grind that you don't want to do. It will remove your paint and prep the floor in one step. You can coat the next or same day.

 

[timelinex]

Time:

You are looking at a 3500-4000 PSI + machine. Anything less will likely not have enough power to remove your paint. Once fully removed you will need to acid etch at a minimum. This process will also require at least a week to dry properly.

A tried and true method would be the grind that you don't want to do. It will remove your paint and prep the floor in one step. You can coat the next or same day.

Thanks for the advice. Whats a 'fair' price range to have someone come out and diamond grind? (obviously it changes by area)

If its out of my price range, Maybe I'll just powerwash in the next week or two and do the epoxy a month from now. I'm in no particular rush.

 

[LegacyIndustrial]

1.00 per square foot is the going rate.

 

[bull_duck]

This topic is interesting to me as well. I have ten year old color on my three car garage floor. About 600 SF. I have been advised on this forum to diamond grind.

I want a new garage floor and am leaning to porcelain tile. Like the OP, my garage is to park my toys.

I own a John Deere pressure washer that achieves 3800 psi & 4.0 gpm.
Waiting several weeks for the concrete to dry is no inconvenience.

My home garage update thread is here.

 

[retfr8flyr]

What is your water supply like? You are not going to feed a 3500-400psi power washer with the 1/2 inch line that is in most residential houses. I would recommend to just go ahead and grind the floor.


Earl

 

[EMC2]

Are you planning to use any paint stripper before power washing?
That is what I did, and the paint came off really easily. I posted some before and after pics in my thread for reference.

 

[bull_duck]

What is your water supply like? You are not going to feed a 3500-400psi power washer with the 1/2 inch line that is in most residential houses. I would recommend to just go ahead and grind the floor.

Earl

Yep. My water line is 1/2 inch, but my shoe size is USA 12. I did not know about the limitation of the residential water line feeding my John Deer. The size the John Deer accepts is 1/2 inch.

Still, I will give it a try. If it works, great. If not, then "plan B."

 

[bull_duck]

Are you planning to use any paint stripper before power washing? That is what I did, and the paint came off really easily. I posted some before and after pics in my thread for reference.

Just read your thread at here. I will follow your example of the combination of mechanical and chemical to strip the floor, including the plastic cover.

Nice garage BTW. My Porsche is 20 y.o. this year. Time flies in the fast lane.

 

[timelinex]

I didn't know you needed to couple it with a stripper. Everywhere I read, it seems like a simple power washer will do the job. My paint is already peeling where the tires are, so I'm sure it has to do with how well the paint is on there...

 

[retfr8flyr]

Yep. My water line is 1/2 inch, but my shoe size is USA 12. I did not know about the limitation of the residential water line feeding my John Deer. The size the John Deer accepts is 1/2 inch.

Still, I will give it a try. If it works, great. If not, then "plan B."

Every high pressure power washer I have ever seen requires an 3/4 inch line for adequate water flow. I had a 3500 psi PW that I burned up using on a 1/2 inch line. Good luck with your JD, it may work fine.

 

[sxk122]

I am not an expert, but here is my one-off experience

There was paint on our garage floor when we bought our house (concrete in garage circa 1956), and I went the powerwasher route because it was free. My wife's uncle had a Troybuilt powerwasher that he loaned me.(I think this one http://www.lowes.com/pd_375831-348-020489_0__?productId=3606418) 90% of the old paint came up with just the pressure washer and patience The remaining tough sections I scratched/ scraped at, and sprayed again until they came up. I let it dry a few days, did the acid wash, and then let it dry a week and a half. I went with the Sealkrete floor paint and clear sealer as I couldn't afford epoxy, and by the time everthing was finished I spent around $125. I would have loved legacy's or griots epoxy, but I didn't have the extra $500 and I needed to get stuff moved into the garage.

My floor has held up quite well. I did the floor in September of 2011. The giant crack in the center caused a bit of grief, I ended up treating it like an expansion area and using a backer rod and caulk. I also have one spot right by the door that has flaked up (There was a flash rainstorm when I was doing the floor, and the garage door was open-- the flaky corner got wet from the water splashing in)

Newly laid

I do park on mats as a precaution for hot tires, but actually like it as it helps contain mess and water.... Here is what the floor looks like now

 

[EMC2]

Just read your thread at here. I will follow your example of the combination of mechanical and chemical to strip the floor, including the plastic cover.

Nice garage BTW. My Porsche is 20 y.o. this year. Time flies in the fast lane.

Thanks.
I agree with some of the other posters that a pressure washer alone could work on some, or a lot of the paint depending on how well it is holding. I think however, that there will almost always be some stubborn spots, and I was definitely not interested in using a scraper. As you'll see in my pics, I even had some spots that required a second application of paint stripper.