Two questions that we are often asked is how to recoat or apply a new coat of epoxy to an older epoxy floor that has already cured and can you apply a clear coat to an older epoxy garage floor coating? If you’ve done a little bit of research on epoxy application, then you know how important floor preparation is. So let’s discuss how to determine if your floor qualifies for a recoat and then how to prep the floor before you do.
When can you apply epoxy over an older coating?
There are many examples of when you can apply a new coat of epoxy over an older cured coating. The most common of these are for people who had previously applied a color coat and now realize that they want the glossy looks and advantages of adding a clear coat.
Sometimes it’s as simple as someone who planned a multiple coat flooring system and waited too long between coats, allowing the epoxy to cure, before applying the next coat in order to get a chemical bond.
Another reason is to renew the clear top coat. After many years of service in a busy garage, the clear top coat of an epoxy floor can start to show its age. With the proper floor preparation, you can add another coat of clear and make the floor look brand new again.
And then finally, you may have an older existing coating that is showing wear from years of heavy traffic and getting thin. As long as the floor is not experiencing any delamination issues, many times you can recoat right over a worn epoxy floor to create a brand new looking finish.
As long as the existing garage floor coating is a 2-part resinous product such as epoxy, polyurea, polyaspartic, or polyurethane, then you should be able to apply an additional coat of a compatible product without issue. However, to be safe you should always consult with the manufacturer of the new coating first.
When not to apply epoxy over an older coat
If the existing epoxy floor coating is peeling up or showing other signs of delamination, then you do not want to epoxy over it. There are bigger issues at play here that are causing the delamination. Applying a new coat of epoxy over such a coating will only lead to more problems. A complete removal of the old coating by grinding would be required.
If the coating is fairly worn with more concrete showing through than there is epoxy, then you will want to start fresh by grinding the floor.
Do not attempt to apply epoxy over existing concrete sealers. These need to be removed first as epoxy will not adhere to them. Also, floor paint is not a good base for epoxy and needs to be removed as well.
How to prep epoxy for another coat
The key to applying a new coat is to mechanically rough up the surface of the older coat to create enough bite for the epoxy to adhere to it. There are a couple of ways to achieve this.
The first is to use 120 grit sandpaper on an orbital sander or pole sander like this one at Amazon
. What you are trying to do is rough up the surface, not remove it. The surface should look deglossed after sanding.
Once done, sweep up the heavy stuff and then vacuum the entire floor with a shop vac. Next, use denatured alcohol on a small towel and wipe down the entire surface. The denatured alcohol will remove all the fine dust particles, evaporate quickly, and make sure that the surface is clean.
The other option is to use a floor maintainer (buffer) with a 100 grit sanding screen. You can usually rent these fairly inexpensively from your local home improvement center. They should have the sanding screens to purchase as well.
This method will go faster than the pole sander and cover a lot of floor quickly if you have quite a bit of square feet to prep. Just remember to occasionally check the sanding screen for wear and to make sure it hasn’t clogged up. After you are done, vacuum the floor and use denatured alcohol as described with the sanding method.
If you have an older clear coat that you want to renew, then you will want to use 80 – 100 grit sandpaper or a 60 – 80 grit sanding screen first to actually remove a small layer of the coating. This will help to eliminate any deeper scratches and/or embedded dirt that has marred the finish.
Do the same if you have a worn coating that is adhered very well but has some spots where the coating has worn through to the concrete. The more aggressive grit will insure that the bare concrete will be prepped properly as well.
Floor prep such as this goes fairly quickly. Once you wipe down the floor with the denatured alcohol, your floor is ready for a new coat of epoxy or floor coating of your choice.
Yesterday I put down the solid rock grey and sprinkled the decorative chips. Today I realized there are some bare spots. Can I put another coat over that coat without sanding? My concern is that the decorative chips will not allow the two coats to adhere properly.
Hi Evan. If you are referring to RockSolid, then yes, you can apply another coat without sanding. RockSolid allows for up to a 7 day recoat window. The decorative chips will not create a problem.
I have an existing shop floor that had been coated with a 2 part epoxy 20 years ago. Over the years it is starting to show it’s age. I also park a very large/heavy dual wheel vehicle in the building and the coating has lifted where the rear dual wheels sit. I do not know the brand of the original coating. What is the best procedure to use in renewing this floor?
Hello Michael. You didn’t mention what type and quality of coating you want to use, so this will be general information. For a coating that old of which you don’t know the make or history, we would recommend removing it entirely to ensure the best adhesion for a new coating. However, if it has only lifted where the rear wheels sit and is solid everywhere else, then chances are decent that it will remain so. If you choose to not remove it, we would recommend roughing up the entire coating with 100 grit sandpaper or an 80 grit sanding screen as we mention in the article. The areas where the coating has lifted should be treated with a concrete grinding wheel if you can. Once the floor is prepped, we would recommend coating only the bare concrete patches first. This will act as a primer to even up the level of the coatings and prevent that area from telegraphing through. Once it has cured long enough, you can then coat the entire floor.
I recently applied a rustolem epoxy paint down in my garage. Now that it’s dry I see that some spots are darker than other parts . Can I just repaint the garage over to make it look better
Yes, you can DJ as long as you are withing Rust-Oleum’s 76 hour recoat window. If you are past that you will need to degloss the surface by roughing it up with 120 grit sandpaper before applying another coat.
Hello. I purchased a Rustoleum Epoxyshield garage kit in grey. I’m past the return period but my wife wants the floor to be something other than grey, since we are using the area for a kids play-room. I was wondering if I could use one of the Rustoleum stain kits with the grey to create a colour? I realize they are intended to be used with the clear kit.
Thanx Marc.
No, unfortunately that will not work Marc. Colored stain is not compatible with the resin tint base that is used for epoxy.
Hello,
Love your site! I’m a new homeowner, so trying to learn as much as I can.
We had the garage remodeled with a new concrete floor that has cured for 60 days. Last week, the contractor added a ‘Glaze n Seal’ Lacquer to give it wet look… but this doesn’t look at all.
I’ve decided that I want to add an epoxy coat to get a slick/professional looking floor. Do I need to remove the lacquer sealer with a grinder or just the buffing machine with 60 grit? After sanding or grinding, will I still need to etch the concrete with chemicals?
Thanks!
Hi Tim. Yes, you will need to completely remove the sealer. It’s an oil based sealer that will not compatible with other coatings and will block proper adhesion. The best way is to grind. This will remove the sealer and properly profile the surface for epoxy at the same time. Etching is not required after grinding.
Thank you so much for your quick reply! OK, i’ll rent the buffing machine with the diamond head grinder from home depot (and a vacuum).
Last question – is there any 100% solids over or similar kit you recommend that I can pick up from Sherman-Williams/Home Deport/Lowes? I can’t wait for delivery, since I need to do the floor this weekend.
Thanks again!
You are really limiting your options if you are trying to source product in less than two days, Tim. Home Depot doesn’t carry any high solids product. They only carry thin build DIY garage floor kits. Lowes sell Epoxy-Coat, which is a 100% solids product, but I don’t believe they stock it anymore and it has to be ordered in. You can check your local store. Sherwin Williams has a product called ArmorSeal 1000HS. It’s approximately 70% solids. Don’t use H&C Shield-Crete by them, however. It’s the same as the home improvement DIY coatings. Also, make sure you use the Diamabrush removal tool and not the prep tool. The prep tool will not remove the coating as well. Grind dry if you can. If you grind wet, you will need at least a full 24 hours if not two days for the floor to dry out before you can apply a coating.
Shea, thanks so much. This is great info. I actually was planning on going with the Sherwin-Williams ArmorSeal 1000HS and a top-coat. My garage is a converted office, so no vehicles will be on it. ArmorSeal should be good enough.
Good advice on the Diamabrush – and will do it dry. I’ll vacuum the dust and use the denatured alcohol after to make sure it’s clean.
THANK YOU AGAIN!!!
You’re welcome!
My garage floor is painted with a grey paint. Not sure if it is a 1 or 2 part epoxy coating. It has a matte finish. It was applied by the builder and is over 12 years old. It is not chemical resistant to gasoline. I have performed a moisture test with plastic taped to the slab and a duct tape lift test. Other than wear at the front edge of the garage slab where the car tires roll over, it seems to be bonded very well. I would like to apply an Epoxy or Rocksolid coating over the existing floor without grinding. Preferably something that is more chemically resistant. I have degreased and rough sanded the floor.
The question is without knowing the composition of the original floor, what type of coating should I use? What other preparation do I need to perform.? Do I use the etch on an already coated floor? Should I apply a cement primer? Or can I simply apply the new coating directly on top of the existing coating?
Hi Elvis. Keep in mind that how well the new coating stays adhered in the long run depends entirely upon what it is adhered to. Since it will not be applied to bare concrete it will be dependent on the unknown coating you are applying it to. More than likely the current coating is paint. If it was a 2-part epoxy or similar product it would be resistant to gasoline. With that in mind, you need to use a water based epoxy product or very low solvent product. RockSolid will work since less than 4% is solvents. Anything higher than that will soften the paint and the coating will not bond. Water based Rust-Oleum EpoxyShield will work as well. The rough sanding is all that is needed for prep. You cannot acid etch paint. However, any bare concrete will need to be clean and porous to accept the coating.
Hi – I would like to apply a 100% solids epoxy clear coat to a garage floor that has previously been coated with Rustoleum water-based epoxy. The coat has been in place for about 3 years. There is some peeling but only from hot tire pickup…everything else has bonded well.
Am I able to prep the floor as you recommended and apply the clear coat epoxy?
Yes you can, Tom, but we wouldn’t recommend it. The 100% solids epoxy is expensive compared to the water based Rust-Oleum epoxy. Also, it will have no effect on how well the Rust-Oleum epoxy stays adhered to the concrete. It’s similar to applying an expensive clear coat over an old car that doesn’t have a very good paint job to begin with.
Ok,, thanks Shea. I see you recommend using denatured alcohol as a final clean-up agent. I went to the store to get some and read the warning label, which said that it should not be used to clean floors as it is a fire hazard. Of course, this made me nervous and I did not purchase it.
Is it really a problem? Is there another agent that could work as well?
Thanks.
You don’t want to dump it out on the floor near an open flame, Tom. What you do is pour some out on a lint free towel, close the lid, then wipe down a section of the floor. It evaporates very quickly and you can apply the coating immediately after it is wiped down.
hello- I recently put down epoxy shield with the color flakes- the temp was in the 60’s but later that night dropped into the low 50’s. It is now 2 days later and it seems nice and dry, not sticky. Can I apply clearcoat without having to scuff up the original coating? Thank you (love your site)
Hi Matthew. Rust-Oleum allows up to 76 hours to recoat before you need to rough up the surface. Just make sure when you recoat that it is within Rust-Oleum’s temperature guidelines or it will not cure properly.
Can I apply epoxy on a wall that has been applied primer on ?
Hello Telco. Epoxy can only be applied to a primer that is epoxy based. If it’s a standard paint primer it will not adhere. Also, epoxy is not made for use as a wall paint. Because it cures slowly and does not dry like regular paint, it can slump and run if applied to smooth surfaces.
My floors were super dirty and I cleaned them with pinesol. Now the shine is gone. Can I put a clear coat over it?
PineSol leaves a residue that will dull the finish of the coating, Chealsi. Try cleaning the surface with 1/2 cup ammonia to 1 gallon of hot water. It should remove the residue left behind by the PineSol. If your floor was dull to begin with, then yes, applying a clear top coat will provide gloss.
I covered a floor with Rust-Oleum rocksolid, but ran into some color differences between the two packets. Rust-Oleum customer service was great and refunded my money and send me alternate mixing instructions for a second coat. My concern is that painting over the decorative chips will cause a rough texture and will not have the gloss the floor currently has. The coating system says it goes on 3 mils thick and I think the chips are 4 or 5 mils.
No worries Russell. Because you are covering the decorative paint chips, the coating will still have the same gloss. Remember that you have 7 days to recoat. If you have to wait longer, it will require that you degloss the surface by roughing it up with 120 grit sandpaper before application.
Hello, I just purchased RockSolid grey and the clear (want a super shiney garage. I am applying it over existing two part epoxy that I put down on a new garage floor 7yrs ago. Once I scuff up the floor do I need to use the etch kit that came with the RockSolid or can I just vaccume wipe clean and apply? Or can I clean skip the sanding and use the etching?
-existing coating has no peeling just scuffed and abused by me. Lol
Thx
Dennis
Once you rough up the floor, Kuhn, sweep and vacuum up the debris then wipe the floor down with denatured alcohol on a lint free towel. This will remove any left over dust. Once you do this you are ready to go. Etching solutions only work on bare concrete and are ineffective on paint and coatings.
Can I apply the older 2 part epoxy with chips then once it cures follow it up with Rock Hard poly clear coat ? I have used the epoxy in the past and familiar with it and also if this works and get the same finished product while saving money.
No, Ryan. Rockhard (assuming we are discussing the same product) is a polyurethane clear coat for wood finishes. It is not compatible with epoxy floor coatings and it is not designed or formulated as a wear surface for foot traffic, automotive traffic, and automotive chemicals. You would need to use a polyurethane floor coating for concrete.
Hello,
I appreciate your website and willingness to answer customer questions! I recently had a professional contractor coat my basement floor with a full broadcast epoxy flake floor. Overall, I am satisfied with the look (much better than the peeling painted concrete I had prior). However, I did not realize just how “wet” and shiny the floor would look. Under light, the rigidness of the flakes almost gives a slight sparkling bubble look. My question is, is there any way to reduce this look/shine while maintaining the integrity of the floor structure? I saw in a previous post that a consumer used pine sol and accidentally took away the gloss. I actually want to reduce the gloss. Would lightly sanding achieve this affect? If you get a chance, I would appreciate any advice you have. Thanks again!
Hello Jack. It’s funny, but most people strive to obtain your current problem with a new floor. What we recommend for your case it to give your floor a little bit of time and traffic. The natural wear from light dust and dirt under foot actually creates microscopic scratches that will reduce the glossiness somewhat. If you don’t want to wait, you can always apply coat of matte floor wax. It will take the glossiness out. This is an example of a good product. You don’t want to lightly sand the top coat. Doing that will dull it out completely and make it much harder to clean.
Hi, I have previously bought the rust oleum epoxy shield kit and haven’t put it yet, just yesterday i found about the rust oleum rocksolid and supposedly is better and also bought it thinking in returning the other one later, I have a doble car garage and the thing is after reading a lot, everyone says one kit is not be enough, that’s killing me as a can’t afford to buy doble the product, now comes my question, can i use the epoxy shield with no flakes as a firt coat to cover my bare concrete and then after is cured apply the other as second coat? I believe I understand they’re not the same, would it be a problem?
Hello Hery. Yes, you can do that if you wish. We recommend letting the first coat cure for 48 hours and then lightly sand it with 120 grit sandpaper before applying the RockSolid kit. The two may not be compatible if you try to recoat earlier to get a chemical bond. A word of advice; we have found that if it’s not in your budget to do a coating correctly the first time, it’s best to wait until your budget allows for it. Patching different kits together is not always a good idea.
Do you do floors in casa grande, az? Thanks.
Hi Lee. We don’t sell or install product. We are an informational website only.
Great Article -Question, have a epoxy floor green with anti skid flakes. Its in fine shape no peeling, but I want the metallic look in blue with the light colored swirls. So ,can I just prep with 80 grit, clean and then– Do I have to apply a black base to start fresh, then apply the blue and clear coat? Thank you
Hi Kris. A black epoxy primer is generally required in order to get the deep and true blue look of a metallic epoxy. A green under coat can change the look of the blue. Plus, the black primer will do a good job or providing a nice clean base over your older floor.
Thank you! Much Appreciated
I have epoxy kitchen counter tops, however I am not able to sit a cup of coffee on them unless I want to iron out the ring left by the heat. What type/brand of epoxy should I use to recover the counter tops? Any suggestions would be great.
Hi Rebecca. Epoxy can have different levels of heat tolerance based on the formulation. Also, unlike garage floor epoxy, epoxy made for counter tops is water clear. You may want to contact these guys for more information on heat tolerant epoxy for counter tops.
If your current epoxy extremely clear and in good shape other than not being heat tolerant, another option would be a water clear polyaspartic top coat. Polyaspartic is very heat tolerant and less scratch resistant than epoxy. It would require roughing up the current surface with 100 grit sandpaper before application. Many garage floor vendors carry polyaspartic, it would just be a matter of finding one that sells it in quarts, not gallons.
Hello Shea
My new garage floor was apoxy sealed in gray with speckles 1 year ago .
I covered the floor with roll up cardboard
To protect it when I worked on my truck .
I made the mistake of taping the cardboard to the floor in places .
When I removed the tape it pulled the apoxy up and exposed the concrete .
I now have several bare patches approximately 2” square . How can I fix this ?
Gerry
Hello Gerry. It sounds like either poor concrete prep was done or it’s not an actual epoxy coating – just paint – or both. Epoxy cannot be pulled up by tape. Do you know exactly what was used?
I have install the rustelium epoxy on my garage. I installed the flakes incorrectly making a bad cosmetic looking. It’s being six months since I applied it. Can I put a new epoxy over the old one or I have to remove it??
Yes, you can apply a new coat over the old one, Luis. Just prep the floor as described in the article.
On Sunday we used Rust-Oleum epoxy with flakes. The following day my husband clearcoated the garage with the Rust-Oleum brand . Later on that day the wind was horrendous and sand blew in from the garage door, back door and an air vent. There is dark brown sand embedded in a few areas of our gray epoxy now. What would be the best ways to remedy this? It has been 4 days since epoxy paint and 3 days since clear coat
Hello Traci. We are sorry to hear what happened. The good news is that the debris is in the clear coat, not the color coat. What you can do is sand out the debris in the clear coat and then apply a new coat of clear. This will require roughing up the entire floor with 120 grit sandpaper since you are past Rust-Oleum’s recoat window. We recommend using 80 grit sandpaper for the areas with debris.
Good morning I used the Rustoleom garage paint and stain in battleship gray. My plan is to now put the rustoleom epoxyshield product I used the first product to seal the concrete. I pressure washed degreased and dry mopped with a damp mop to remove the dust floor was very rough to begin with. After reading these questions I’m doubting my plan. Also if I can proceed forward with some light sanding, how long would I have to wait on applying another coat of the epoxy shield? After the second coat of the gray I barely used one gallon. If I can do the floor with one can of part a and b I’d like to use the other can to continue to increase the thickness and durability.
Ron
Hello Ronald. Can you please tell us exactly which products you plan to use? In other words, what is the exact name on the package? Paint and stain are two completely different products, so I’m not sure what you are trying to do.
I’ve used two coats of rustoleum concrete and garage floor paint and primer in battleship gray. “ 225380 battleship gray” is what’s on the barcode. Then on top of that I am using the rustoleum “epoxy shield garage floor coating kit in gray gloss”
Barcode “Gray 261845”.
Yikes…. OK, you were correct to doubt your plan, Ronald. The Battleship Gray garage floor paint is just an acrylic concrete paint. It is not compatible with the actual 2-part EpoxyShield Garage Floor Coating. This article here explains the differences. An epoxy coating requires that you etch the concrete in order for the thicker epoxy coating to penetrate and form a good mechanical bond at the surface. Acrylic concrete paint does not require that. Paint does not bond nearly as well as epoxy either. This is one of the reasons paint peels up much more easily on a garage floor. Also, if you want to apply the epoxy over the paint you will need to let the paint dry completely and then rough up the surface with 120 grit sandpaper. Epoxy cannot be applied directly to paint or it will peel. It’s not worth spending the money to apply epoxy over paint since the paint will still come up just as easily no matter what you apply on top of it. In other words, for the best outcome you would have been better off to just etch the concrete and apply the EpoxyShield Garage Floor Coating on its own.
Damn the initial idea was mine of course I talked with Home Depot guy in the paint Dept…you know how that story goes.
So 120 grit rough it up and pray it stays down.
Yeah, unfortunately we know the story. It’s why we did an article about home improvement centers when it comes to concrete coatings.
Hi i coated my basement floor with Rust Oleum Epoxyshield and then a top coat of their clear “high gloss” formula. Everything is great… except for i cant stand the high gloss formula. And also i used a cheap roller that left the fibers in the top coat. I would like to put a new clear coat on top (after lightly sanding), and i want it to be a satin or semigloss finish. Would it work to use a product like Top Secret coatings TS-66 SUPREME URETHANE CLEAR KIT ?
Hi Samuel. Yes, that product will work nicely for what you want to accomplish.