Getting ready to start epoxy project

[timelinex]

Hello everyone. I just bought my first house and epoxy'ing the garage is going to be our first project. I already bought enough black epoxy-coat from lowes and now I'm just waiting for it to be delivered. I have done my research and read alot of threads on here, but I have a couple questions remaining before I embark on this....


I plan on painting my walls as well, should I do that first or after? I assume it shouldn't really matter as long as I'm careful?

The next issue I have is the paint that was put down on the concrete before. I couldn't find the type of paint that was used, but it looks like normal concrete paint. here are some pics.

My friend told me that he just used acid etching over his paint and then just epoxied right over it. According to him, the epoxy turned out level and its been fine for a year or two. Everything I read on here makes it seem like that leaving the paint on will absolutely mean it starts peeling of immediately.

I assume I will have to remove this paint however. Can someone recommend a method? I know diamond grinding is the 'best' way. But unless its absolutely necessarily, I would rather not spend another couple hundred on renting and then more time and tedious labour.

I have read that you can just pressure wash it off, but then somewhere else I have read that pressure washing before applying epoxy will lead to absorbed water in the concrete, which will ruin the epoxy within a year.

The other thing I have read is using special liquids that remove paint. Any info on this?

I know that prep is key. That is why I'm asking how important diamond grinding is vs the other steps. I understand that diamond grinding is the best, but if an easier method gives me 9 years instead of 10... I'm ok with that compromise.

Lastly, do you guys do anything different with the portion of the garage that is exposed, with the doors closed. I think this epoxy coat has a little bit of UV resistence.. But here in AZ , that portion will be getting a beating from the sun. Anyone add anything extra to that portion of the floor?

 

[LegacyIndustrial]

You already know what to do. Diamond Grind or call your local Home Depot regarding a "diamabrush" head mounted to a floor maintainer machine. Excellent tool, very easy to use and perfect for your application.

Acid etching a painted surface will do little and a pressure washer may strip off some paint but won't profile for the next coat.

Lastly, if you are going through all this trouble make sure you are using a good product.

If you are using a black epoxy, it will fade if under heavy sun. Consider topping with a black pigmented urethane. It will do fine.

 

[timelinex]

You already know what to do. Diamond Grind or call your local Home Depot regarding a "diamabrush" head mounted to a floor maintainer machine. Excellent tool, very easy to use and perfect for your application.

Acid etching a painted surface will do little and a pressure washer may strip off some paint but won't profile for the next coat.

Lastly, if you are going through all this trouble make sure you are using a good product.

If you are using a black epoxy, it will fade if under heavy sun. Consider topping with a black pigmented urethane. It will do fine.

Thanks for taking the time to reply.

Can you point me to a thread or any other information on the diamabrush with a floor maintenance machine that you mentioned. Is this the machine with a T handle (here). Its different than the 'floor sander', which I do not want, correct? I just called my local home depot and they didn't know what a 'diamabrush' is, they asked if I'm talking about a hex pin brush, designed to remove glue of the floors I think. Is there a different name this goes by? I sure hope its a different one, because they said renting this is $90 just for the brush alone!

Should it be ran with a dry floor or wet floor?

I have heard it mentioned once, but I have never seen anyone talk about how they used it to strip their garage floor paint, so it leaves alot of questions. Would I still have to acid etch after it, or does it take the place of that just like the grinding?

I know I can probably figure alot of this stuff 'as I go', but I like being prepared before taking on a project.

Thanks!

 

[timelinex]

Ok I THINK I found more info on it. Looks like I need one of these tools...

Since I have paint, am I going to need both the removal tool and the concrete prep tool since I need to remove the paint. Or will the concrete prep tool have no problem removing the paint and then prepping the concrete simultaneously.

 

[LegacyIndustrial]

Link: http://legacyindustrial.net/cart/concrete-prep-tool-p-167.html

 

[trevor_s]

These guys are insane not wearing some sort of respirator mask!

 

[LegacyIndustrial]

I gave them hell. If the dust doesn't get them the booze and cigarettes will.

 

[timelinex]

Ok I just realized , for the edges I'm gonna have to use my small angle grinder right? What attachment do I use? Do I seriously need to buy a $100 diamabrush attachment?

 

[pauls_workshop]

Hi Timelinex,

I'm new here and also doing my first epoxy job (thread just started on it), but I've learned a couple things on the grinding I thought I'd share. I'm doing a basement shop in about a 1 car garage space. I simply bought a good quality diamond wheel myself and put on my 4.5" angle grinder. I got a Dewalt DW4774 wheel. This is a very sweet wheel. I even put a review up on Amazon about it a week back. It is about $60 at Lowes, but I just saw that you can get it around $40ish from the internet now if you look. I'm about 1/2 done with my grinding now. For corners if nothing else, this kind of wheel is great. I'm doing the whole job with it in a cheap grinder. They also have a 7" version like this one, and I think with a 7" grinder, you could do a two car garage space just with that if you wanted to. Probably would take about 12 or more hours of grinding to do it. I would think the more professional equipment like the diamabrush could do that in probably 3 hours or less, but it would be much more expensive. Time vs. money.

The grinding should pull off all your paint. If it doesn't, you could use a chemical stripper, but if you do be sure to get all of it out of the cement before trying to coat anything. I'm just grinding and nothing else. Should not have to acid etch if you grind.

- Paul

 

[timelinex]

Paul ,

Thanks for the tips. I have a 3 car garage, so I think using a hand held would be too time consuming. That's why I decided I need to use a big machine. However the costs are really starting to add up considering its just a floor job for a garage. Epoxy was a little under $500, then I find out I need a grinder for another ~115. I'm just hoping there is an alternative to spending another $100 on a diamond piece to be able to do the corners.

Most people I have talked to have just told me to straight up remove any lose paint and just epoxy over everything and it will wprk just fine. I believe the guys on here, since many are actually professionals at what they do, and I don't want to drop $500 on the garage just to have it 'go bad' within a year or two. So that's why I'm planning on doing the grinding. I'm just trying to minimize expenses on this 'simple' epoxy job. I'm just trying to figure out what's actually important as opposed to what is the best, and will just extend the life of the job from 10yrs to 10.5 years.

 

[hofiveo]

If i were you i would hire a professional to do your prep. Not knowing the goin rates out there, i would imagine that for ~600 sq ft it should be in the $0.75 to $1.50 per foot to prep. It is all in the prep and quality of epoxiy/urethane used. Like Legacy Inds. said, put a urethane black coat on top of epoxy, with a clear urethane on top of that(optional).

 

[pauls_workshop]

Yes, Timelinex I'm in the same place as you and making similar decisions! I want a nice space but also don't want to spend too much on it, esp just the floor. The good epoxy is expensive. To save money, I'm willing to put in more time in my case. It is surely a tradeoff. But the benefits of doing the grinding yourself are not just that it is cheaper, but I am getting every last speck of sealer that was on my floor (paint in your case) and also having a much flatter and more consistent floor by grinding too. See with the little 4.5" wheel, you CAN go into any depression or region the larger wheels would not let you go into and just do a local smoothing out there. Works really great for that. It is an ADVANTAGE over a larger grinder for this type of thing and very useful just for that and corners if nothing else. Also, I find that I can have good control of the grinding with the small size and not have it get away from me. You can grind yourself to china fast if you don't master the technique required with any grinder. A cheaper diamond wheel than the dewalt could probably be used if just for a small amount of use. The dewalt is really a premium wheel. The 7" size would do really well for you for a whole project. Dewalt wheel in 7" at lowes (double rows of diamonds) is around $100. Some of these professional floor grinders use the same 7" size. The single 7" floor grinders may have a little more power than a good hand grinder, but prob not that much. Anyhow, doing the rental route is a big chunk of the cost of the whole project, esp if you have to do the job in two parts like me with two rentals and not one, so an area I decided to save on, but not sacrifice anything in terms of prep quality. I don't think I would "leave any paint" on the floor before epoxy. I'd remove all of it myself. I'm even considering a primer coat under the basecoat, but hoping to be able to use a water based epoxy (valspar, rustoleum) as the primer coat to save money there. Importance of proper prep has been emphasized by almost everyone here who has ever done this job.

I'm going to be around $400 for my 1 car garage space in a nice epoxy floor with 100% solids base layer and a cheaper water based clear topcoat with the grinding job coming in less than $100 total for me. $600 or $700 would just be too much for me for this floor job for me. Even at $400 for a floor my wife is rolling her eyes at me beyond the back of her head! Yes, it is possible to do that for my wife ! I'm trying to do the whole shop room project (1/2 the basement space) and utility room closet too for under $2k with walls, electric, lighting, ceiling, floor, drywall, doing everything myself. Been learning alot about construction of walls and electric code in the process let me tell you! Close to the rough inspection on the electric once I get this floor done next. Hope to get that $2k investment out of my house if I ever do sell it later on, but that is not a given with housing these days so want that total cost down for the whole project.

 

[pauls_workshop]

Few more thoughts:

While a diamond wheel is best for grinding the concrete floors, just a "normal" concrete grinding wheel at about $5 or so each on a 4.5" grinder probably would be enough for all the corners if you use a bigger grinder everywhere else and just take you more time for that. For the very very corner, I also used a dremel to handle that. Newer multi-tools like a rockwell or any brand also are amazing little tools everybody should own. I use mine for all kinds of things now that I know what it does. Just vibrates a little bit, but that vibration can cut through drywall, wood, or YES, even cement with a little diamond coated attachment. Could also grind the floor just enough to rough it up for corners I would think. The normal cement wheel on a grinder or other options above would just take a little longer on the corners. You might also need something along all the flats for the walls too, depending on the clearance you end up with from the edge of the guard on the big grinder and the grinder wheel inside. Prob a little grinder wheel would be best if you need to do the wall flats too. Dremel or multi-tool would be too much for long walls for sure.

If you don't have a little 4.5" grinder, try Craigslist or garage sales! My cheap harbor freight chicago electric just died on me and today I got a replacement craigslist craftsman with a little higher amperage and very little use for all of $20. I love harbor freight for lots of cheap things. I think their grinder is as good as anyone's of similar amperage rating (I just overheated it). Did half my project well for it's $20 new original cost! Another option I'm going to consider is possibly renting a bosch 5" floor planer for the last 1/2 of my project for $23 a day locally for me. That would probably work much faster than the craftsman for the second 1/2 of my job and can accept the dewalt 4.5" diamond wheel no problem. BUT, all my current electric in the whole basement is in 3 outlets only all on the same 15 amp circuit. Just the little harbor freight blew my circuit breaker several times with the vac and lights on with it on the same circuit! The bosch might just fry my whole electric panel with it's amperage! Gotta get my improvement project done to get some real 20 amp circuits in my basement!

 

[LegacyIndustrial]

FYI gang, this is why installers charge and get 5-6.00 psqft. Material costs, equipment costs, labor... it all adds up.

 

[pauls_workshop]

If one has the money, certainly hiring the grinding job professionally has many merits!

My info is just to show that those who are the more ********* do it yourselfers like me and not afraid of ANY challenge in life, can do it themselves for much less cost if willing to put in the hours of prep time. Newer grinder wheels and higher powered hand grinders than before make it more possible now than say 10 years back would have been. Lots of work though! Good luck Timelinex on your choices! - Paul

 

[jose jj jacinto]

hello.

the existing paint will need to be removed and acid washing will not remove it. also removing the existing epoxy will give you a bond on the exisitng floor surface. fyi, most all epoxies state that they are self priming. yes, but prepped concrete whether its ground, acid washed, scrubbed, etc, will out gas. you need to put a primer down.

also, for the walls, the epoxy needs to be a coating for vertical applications not self leveing. the epoxy will roll on the surface, but as its curing, the paint will get hot and sag down leaving an ugly mess.