Painting concrete

[brihvac]

I want to paint my old garage floor. I put de-greaser and power washed the floor real good. The guy that had the house before me worked on his cars in the garage and in a 4' diameter circle you can see the floor stained and water beads on top in that area. The rest of the garage is fine but how do I get this spot to where paint will adhere to it? I have muratic acid. Would that work?
This is not my main garage. I build an addition and that is where I work on my cars. The garage I am painting the floor is a work area for my motorcycle. So that will be the only thing driven on it.

 

[BigGarage]

I want to paint my old garage floor. I put de-greaser and power washed the floor real good. The guy that had the house before me worked on his cars in the garage and in a 4' diameter circle you can see the floor stained and water beads on top in that area. The rest of the garage is fine but how do I get this spot to where paint will adhere to it? I have muratic acid. Would that work?
This is not my main garage. I build an addition and that is where I work on my cars. The garage I am painting the floor is a work area for my motorcycle. So that will be the only thing driven on it.

I really don't know if muriatic acid removes grease but shouldn't your degreaser have removed it? Coating the floor with muriatic acid and scrubbing it real good (with a brush) and then washing it real good was the last preparation step before applying primer if I am remembering correctly when I painted mine.

Dennis

 

[brihvac]

I really don't know if muriatic acid removes grease but shouldn't your degreaser have removed it? Coating the floor with muriatic acid and scrubbing it real good (with a brush) and then washing it real good was the last preparation step before applying primer if I am remembering correctly when I painted mine.

Dennis

I used Castrol SuperClean straight and power washed it with a 3000psi gas power washer with 15* nozzle. The water is beading on top so I am sure that paint/primer will not stick to it.

 

[BigGarage]

I used Castrol SuperClean straight and power washed it with a 3000psi gas power washer with 15* nozzle. The water is beading on top so I am sure that paint/primer will not stick to it.

Scrub it with a brush. That's my suggestion. They have them with long handles for probably $10 or so.

Dennis

 

[garagecabinet]

I used epoxy (decorative) to redo my garage floors

 

[Shea]

No, muriatic acid will not clean oil out of concrete. It reacts with with the free lime and other minerals in concrete to break down the surface and make it rougher. If water beads on the surface, the acid etch will bead as well and will not be very effective if at all.

You may want to try some enzymatic oil cleaners. They take a while to work, but they tend to do a good job of getting rid of the oil. They don't always remove the stain, but the oil will be gone.

Another option is to soak each spot with a strong solvent to soak in. Of course turn off any open flame. Once it soaks in, cover the area with some Portland cement and then cover that with plastic or plywood. The Portland cement acts as a poultice and will draw the oil out with the solvent.

 

[Shiftless]

Shea:

That’s excellent advice.

By “strong solvent” do you mean undiluted Simple Green, or mineral spirits paint thinner, diesel fuel, kerosene, or acetone, or lacquer thinner , or ???

(Let’s hope that nobody interprets that phrase to include gasoline)

 

[Steve in UT]

Lacquer thinner or acetone, don't use an oil based solvent!

 

[Shea]

Lacquer thinner or acetone, don't use an oil based solvent!

Bingo! I should have elaborated more.

 

[brihvac]

Bingo! I should have elaborated more.

Ok, I have lacquer thinner and I will pick up some Portland cement. So I soak the floor with the lacquer thinner, put down the Portland cement, then cover it with plywood? Let it sit overnight? Do I do it more than once? I also assume I should still use muriatic acid and scrub with a deck brush on the floor before I epoxy paint it? The concrete is 79 years old and is not all level or ultra smooth. It has some cracks in it too otherwise I would do a good epoxy instead of just a epoxy paint. I just want to freshen it up and make it look a little better than what it is without spending a fortune on "real" epoxy seeing the floor is not that nice. The garage will not have any car traffic and is only a shop area and I keep my motorcycle in it. I know you are going to cringe but I was going to just use some $35 box store epoxy paint. I am not against spending more money on a better epoxy paint etc, I just don't want to get real crazy seeing the condition of the floor is ehhh. Here is a picture. It is the old garage not the addition (although the addition is just epoxy painted and could really use a redo (8yrs old) which really want to do also). I am open for ANY suggestions or recommendations. The old garage is 20'x20'. My addition is 16'x26'. Thank you in advance

 

[Shea]

Make sure it soaks in well and then let it sit for a few days while covered. There should be enough Portland cement to prevent it all from getting wet or it will quit absorbing. Sweep up and then check if it beads water or not.

1-part epoxy paint can make sense for such a project. Muriatic acid may be a bit aggressive for the paint. You might be better off to just use Rust-Oleum Clean and Etch. It will etch the concrete enough for paint and you won't have to worry about the hazards of acid.

 

[brihvac]

Make sure it soaks in well and then let it sit for a few days while covered. There should be enough Portland cement to prevent it all from getting wet or it will quit absorbing. Sweep up and then check if it beads water or not.

1-part epoxy paint can make sense for such a project. Muriatic acid may be a bit aggressive for the paint. You might be better off to just use Rust-Oleum Clean and Etch. It will etch the concrete enough for paint and you won't have to worry about the hazards of acid.

Shea,
If I wanted to re coat the addition do I have to get up all the existing paint or can I just degrease and go over top of it again?

 

[SGKent]

I had three or four coats down and then had to remove all of them with a heat source and razor scraper. Once you start painting, repainting is the only thing you can do when it gets scuffed and dirty. Next time the paint comes up on mine I will have it professionally coated. Paint is nice when new but it doesn't last regardless what people tell one. But we are in California and can't get the stuff like they used in the 1950's that lasted 1000 years.

 

[Shea]

Shea,
If I wanted to re coat the addition do I have to get up all the existing paint or can I just degrease and go over top of it again?

I would recommend going over it real quick with 150 sandpaper on a pole sander. A green scrub pad on a floor maintainer will work also and is much quicker. You just want to rough the paint a little in order for the new to stick.

If the paint is already roughed up from traffic, a good cleaning will most likely work. Paint doesn't need as much prep as coatings do for reapplication.

 

[brihvac]

I would recommend going over it real quick with 150 sandpaper on a pole sander. A green scrub pad on a floor maintainer will work also and is much quicker. You just want to rough the paint a little in order for the new to stick.

If the paint is already roughed up from traffic, a good cleaning will most likely work. Paint doesn't need as much prep as coatings do for reapplication.

Ok, great. I will probably degrease and sand/scrub. Should I wash the floor down after that or just vacuum it? Here is what I used and it actually held up good with chemical spills/brakekleen, etc. https://www.lowes.com/pd/Seal-Krete...poxy-Actual-Net-Contents-123-fl-oz/1000180223
Do you suggest anything different? I ask because I will buy enough to do both floors if there is something better.

 

[Shea]

Just do a damp mop with clean water. I would recommend staying with the same paint product if you were happy with its performance. You really are not going to find anything noticeably better when dealing with 1-part epoxy paints.

 

[brihvac]

Just do a damp mop with clean water. I would recommend staying with the same paint product if you were happy with its performance. You really are not going to find anything noticeably better when dealing with 1-part epoxy paints.

Thank you Shea. I soaked the area in the old garage with lacquer thinner, put a thick layer of Portland cement on it, and covered it with plywood. I will leave it till Friday and see what it looks like afterwards. I have Castrol Super Clean I will scrub the entire floor down with after and I also picked up the Rustoleum etch and clean for the final prep scrub. How long should I let the concrete dry before coating? Remember it's uncoated 79yr old concrete.

Thank you for all your advice. I really appreciate it

 

[Shea]

With all that water from cleaning and etching, I would wait a minimum of 24 hours. Longer if the humidity is up at all.

 

[BigGarage]

Ok, I have lacquer thinner and I will pick up some Portland cement. So I soak the floor with the lacquer thinner, put down the Portland cement, then cover it with plywood? Let it sit overnight? Do I do it more than once? I also assume I should still use muriatic acid and scrub with a deck brush on the floor before I epoxy paint it? The concrete is 79 years old and is not all level or ultra smooth. It has some cracks in it too otherwise I would do a good epoxy instead of just a epoxy paint. I just want to freshen it up and make it look a little better than what it is without spending a fortune on "real" epoxy seeing the floor is not that nice. The garage will not have any car traffic and is only a shop area and I keep my motorcycle in it. I know you are going to cringe but I was going to just use some $35 box store epoxy paint. I am not against spending more money on a better epoxy paint etc, I just don't want to get real crazy seeing the condition of the floor is ehhh. Here is a picture. It is the old garage not the addition (although the addition is just epoxy painted and could really use a redo (8yrs old) which really want to do also). I am open for ANY suggestions or recommendations. The old garage is 20'x20'. My addition is 16'x26'. Thank you in advance

Please do show some more pics of the 64-65 Falcon. I've had 4 of them and would love to see more of yours.


Dennis

 

[brihvac]

Please do show some more pics of the 64-65 Falcon. I've had 4 of them and would love to see more of yours.


Dennis

1965 351 bored and stroked to a 427. Toploader 4spd and 4:11 with Detroit locker

 

[Shea]

Totally missed the Falcon in the initial pics. Too focused on the garage floor
That is sweet! I've been talking for the last 5 years about doing something similar, but with a 347 stroker.

 

[BigGarage]

1965 351 bored and stroked to a 427. Toploader 4spd and 4:11 with Detroit locker

Thanks for the pictures. That's a very nice car.

Dennis

 

[brihvac]

Totally missed the Falcon in the initial pics. Too focused on the garage floor
That is sweet! I've been talking for the last 5 years about doing something similar, but with a 347 stroker.

The lacquer thinner and Portland cement worked! No beading anywhere now. Today I mixed Simple Green and Castrol Super Clean in a bucket with water then sprayed the floor in sections with straight Super Clean, as well as the mixture, and scrubbed the entire garage floor. After that I used the Rustoleum Clean and Etch and scrubbed that in, rinsed, scrubbed with just water, then rinsed 3 more times as Rustoleums instructions. The floor really lightened up in color so I am assuming that was the etching. Gonna let it dry for a few days and hopefully I can get a warm day next week to paint.

 

[Shea]

 

[brihvac]

Shea, I have another question.
The paint, and all paint, says the floor has to be 50* to coat. What if its coated above that and then it dips down below that? Is the only thing that it will take longer to dry? I have heat in the new garage that does creep into the old garage and I have fans to blow it in there if that will work. Was looking at coating tomorrow (Sunday), then 2nd coat on Monday. (*please click on the "attached image" of the weather*)Or should I wait a week or so? What are your thoughts? Attached is the weather for my area.

I also would like your opinion. As you can see by the one picture that there is no threshold on the door. So a part of the floor is actually outside. At first I was just going to tape a line where the door hits and just do the inside. I am worried that having that paint line that it will be prone to chipping right on the line. On the other hand if I paint it out to the end, will the weather tear it up. Also what would look better. What would you do? I am also concerned that if I paint the outside part in the time line I want to; it is supposed to rain on Tuesday and if the wind blows the rain to the door I do get a little water creep into the garage. Will it getting wet the day after the final coat mess it up?

 

[Shea]

Your big if factor is the rain expected on Tuesday. The manufacturer states that it should not be applied 24 before rain is expected. One advantage is that paint does not take as long to dry as true coatings take to cure. What I would recommend is applying the first coat early in the day as soon as it gets above 50 degrees. Wait the required 4-6 hours and then apply the second coat. This should allow the second coat enough time to dry before it is affected by the cooler temps. Plus, it looks like it's only going to dip below 50 by a couple of degrees. The second coat would then have close to 48 hours before the rain comes and it should not be affected.

I would run the paint out the door to the expansion joint. Since the paint is acrylic, it will not amber from the sun. Even if the weather does eventually affect how it performs, it's easy enough to paint over again since it's paint and not an actual coating.

 

[brihvac]

Your big if factor is the rain expected on Tuesday. The manufacturer states that it should not be applied 24 before rain is expected. One advantage is that paint does not take as long to dry as true coatings take to cure. What I would recommend is applying the first coat early in the day as soon as it gets above 50 degrees. Wait the required 4-6 hours and then apply the second coat. This should allow the second coat enough time to dry before it is affected by the cooler temps. Plus, it looks like it's only going to dip below 50 by a couple of degrees. The second coat would then have close to 48 hours before the rain comes and it should not be affected.

I would run the paint out the door to the expansion joint. Since the paint is acrylic, it will not amber from the sun. Even if the weather does eventually affect how it performs, it's easy enough to paint over again since it's paint and not an actual coating.

Think I should wait a week or so till there is no rain in the forecast or do you think if I get both coats on tomorrow, and leave the heat on in the garage a couple days, I should be OK? I think I have a big roll of plastic that I can actually cover up the entire outside of the garage door and the outdoor painted area to protect it from the rain on Tuesday. I got the heat on now. I might go out tonight and do my 1st coat cut in.

 

[Shea]

That's up to you You could certainly get both coats down tomorrow, but there is nothing wrong with waiting if you are not in a hurry. Just keep it clean. The following weekend looked worse according to your weather forecast, so you may have to wait a couple of weeks if you do.

 

[brihvac]

That's up to you You could certainly get both coats down tomorrow, but there is nothing wrong with waiting if you are not in a hurry. Just keep it clean. The following weekend looked worse according to your weather forecast, so you may have to wait a couple of weeks if you do.

Got both my coats down by 5pm. Beautiful day! Looks good. I will get pictures tomorrow. I was surprised that the initial coat took 1 1/2 gallons and the second coat took a gallon. Did not think I would use that much paint. Also had to switch to a 3/4 nap roller. 20'x20'
One more question about the new garage when I do it in a few weeks. Seeing it is already painted the same color I am repainting it; should I do 1 coat or 2. It does look like the existing paint has darkened some(color look different even though it isn't). The only reason I am asking is I might pick up another gallon from the same lot # as the gallon I have so there is no difference in color if I run short.

 

[brihvac]

Here’s some pictures. The bright stuff on the floor is just a reflection of something in the sun. I am glad the last coat only took a gallon because it was from a different batch number and it was lighter than the original gallon I put down on the first coat.

 

[Shea]

One coat is really all that is needed since the original coats have stayed adhered. Trying to build mil thickness with paint doesn't do much for performance and does a better job of putting a dent in your wallet.

Glad you got the two coats down. The floor looks good.

 

[brihvac]

One coat is really all that is needed since the original coats have stayed adhered. Trying to build mil thickness with paint doesn't do much for performance and does a better job of putting a dent in your wallet.

Glad you got the two coats down. The floor looks good.

Hey Shea,
Question. I have my newer garage ready to re-coat the floor (power washed, de-greased, sanded with 150, mopped, and primed) After I get it painted should I put a gloss sealer on it? Or just leave it painted with no sealer like I have it now? Just looking at better protection, and ease of wiping stuff up. However, I am worried that it I go to re coat years from now (like I am currently doing)that it will be a pain in the *** to prep the surface to re-paint with a sealer on it. Lowes sells only Gloss Seal Krete sealer even though I would prefer low gloss. What would you do?

 

[HotrodHR]

1965 351 bored and stroked to a 427. Toploader 4spd and 4:11 with Detroit locker

That's a very nice and badass Falcon!

 

[Armorpoxy]

Great advice from Shea. We find though that sometimes oil has soaked so far into the concrete that it can’t be fully removed.

Because of that we carry an Oil Stop Primer which is designed to adhere to floors with residual petroleum products in it. Once primed coat with our Armorclad Epoxy. We use this system in auto shops that have years of oil and grease stains.

 

[BigGarage]

I really don't know if muriatic acid removes grease but shouldn't your degreaser have removed it? Coating the floor with muriatic acid and scrubbing it real good (with a brush) and then washing it real good was the last preparation step before applying primer if I am remembering correctly when I painted mine.

Dennis

I used Castrol SuperClean straight and power washed it with a 3000psi gas power washer with 15* nozzle. The water is beading on top so I am sure that paint/primer will not stick to it.

Scrub it with a brush. That's my suggestion. They have them with long handles for probably $10 or so.

Dennis

The lacquer thinner and Portland cement worked! No beading anywhere now. Today I mixed Simple Green and Castrol Super Clean in a bucket with water then sprayed the floor in sections with straight Super Clean, as well as the mixture, and scrubbed the entire garage floor. After that I used the Rustoleum Clean and Etch and scrubbed that in, rinsed, scrubbed with just water, then rinsed 3 more times as Rustoleums instructions. The floor really lightened up in color so I am assuming that was the etching. Gonna let it dry for a few days and hopefully I can get a warm day next week to paint.

If I don't sound too sarcastic because I'm definitely not being sarcastic but what did you scrub the floor with?

Dennis

 

[brihvac]

Got all my concrete projects done.

 

[brihvac]

If I don't sound too sarcastic because I'm definitely not being sarcastic but what did you scrub the floor with?

Dennis

A deck brush. LOL. Saying I scrubbed the floor I would assume that whomever is reading it would know I used a brush of some sorts

 

[msa4033]

brihvac, that looks fantastic! I'm looking at doing something very similar, but I've got some old peeling concrete paint I have to deal with first. Was thinking of power washing it off, but I had a question that maybe you or someone else here can answer...

I have an expansion joint around the perimeter of my garage. Do I need to worry about water seeping down into the expansion joints while I power wash? Specifically do I need to worry about it seeping down into my basement.

Thanks.

 

[brihvac]

brihvac, that looks fantastic! I'm looking at doing something very similar, but I've got some old peeling concrete paint I have to deal with first. Was thinking of power washing it off, but I had a question that maybe you or someone else here can answer...

I have an expansion joint around the perimeter of my garage. Do I need to worry about water seeping down into the expansion joints while I power wash? Specifically do I need to worry about it seeping down into my basement.

Thanks.

If it does seep it will dry. If you look at my smaller garage picture you can see a large crack in it inside the door, No issues with power washing it. See the pictures of my basement? I power washed the floor. It completely dried in a day. For loose paint I have one of those round power wash things you use on sidewalks and a 3300 psi gas washer and it will take up anything that is loose. If you read through this post you will see I used Seal Krete products. Key is (since it's already painted) to sand with some 150 grit and prime it after power washing and drying. I used Seal Krete Lockdown Primer and it works great. For sanding just use a drywall sanding pole. The picture of my garage addition, where the lift is, I painted 8 years ago with Seal Krete when I built it. That Seal Krete paint took a beating in those 8 years with chemicals, oil, trans fluid, antifreeze, grease, etc and still looked pretty decent. Thats why I used it again when I painted the original garage and decided to freshen up the addition. SHEA here was a HUGE help and really knows his stuff. He helped me tremendously when I had questions and ran into issues. If you read through this thread you will see how much he helped me. Advice I will give you is wait at least 10 days before you drive on it and 3 days before you heavily walk on it.

 

[BigGarage]

A deck brush. LOL. Saying I scrubbed the floor I would assume that whomever is reading it would know I used a brush of some sorts

I would never assume when I could just ask.

The floor looks great. Nobody knows how much work it is unless they've done it also.

Dennis