HOW TO PREP & EPOXY PAINT YOUR FLOOR GUIDE
Epoxy Painting A Garage Or Commercial Concrete Floor
FREQUENTLY ASKED APPLICATION QUESTIONS:
Q: Do I need to grind my floor to apply an epoxy coating??
A: Grinding is great if you have the right equipment. Grinding is sometimes necessary, if you are running heavy equipment such as large aircraft, buses, 18 wheelers or fire engines on the floor we would recommend you get the floor professionally grinded. Listen to us, we know what we're talking about since we have a floor grinding business in NJ. Grinding can be done if you have a good heavy duty grinder with a vacuum system designed for that grinder. A shop vac is not s suitable piece of equipment to handle floor grinding, they will clog in two seconds. Real grinding vacuum systems have super high capacity filters with automated pulsing devices that shake the filters clean when they start to clog. Add on Do-Hickies available at some home improvement stores are of little benefit. The floor prep machines at Home Depot are perfect for roughing up an existing coating you want to paint over or removing one of their coatings. You can also use it for a light surface pre cleaning if your floor is really old and dirty prior to an acid etch. We strongly recommend against wet grinding, the mess and stains from the slurry are horrendous. If you use the floor prep machine for what we recommended above you will have a manageable amount of dust. Wear a respirator and sweep up as much of the dust as you can when you're done. You can keep sweeping until all the dust is gone or you can rinse the floor down after you sweep up the initial major piles of dust. Rinsing will save you a lot of sweeping and cleaning time After the floor is dry, rub your hand along the floor, no dust should be on your hand. You can also use a piece of duct tape to test for dust. If dust is still present this is where a good leaf blower comes in handy.
It easy to see from the above image why a shop vac even with some on add on device would not be sufficient for a heavy grind. A heavy grind is needed when your floor is in poor condition, very old and very very dirty or if you are running a lot of traffic with very heavy weight. This is when you need good professional equipment to get the job done in a timely manner. Floor Prep machines and add on vac devices are ok for a light coating removal or light surface scraping followed buy a good acid wash and power rinse with TSP powder. For 90% of residential to medium duty commercial floors using a floor Prep machine and good acid etching will do the job. For heavy commercial or industrial floors or ANY floor that's in bad shape go with a heavy grind.
So to sum up, if you just need to remove a cheap coating that's peeling off or just want to scratch the floor clean a little, use the floor prep machine from Home Depot. If you need to really grind cause your floor is very old and very dirty, you are running very heavy traffic loads or very high traffic volume or you need to remove a previous coating that is still adhered to the floor or your floor is very large and can't get it wet. Make sure you get the biggest grinder you can handle with a set of 20 grit blades, preferably new ones. A good grinder will require a 220 volt connection or have a large gas driven engine. Make sure you get the vac system that has the capacity to handle that grinder! Please note that no matter how good a grinder and vac system you get you will still have to clean up some dust manually. If you don't have a decent tool rental place by you don't rent a piece of junk, you will be grinding forever and killing yourself at the same time. In that case you're better off hiring a professional company, they charge anywhere from .75 cents to $1.00/SF. For the majority of floors a good acid etch and neutralizing is all you need. If you're not sure about what to do, give us a call and we can guide you on what's best for your floor.
Q: Should I shot blast my floor for an epoxy coating?
A: Shot blasting should only be done on industrial floors that are in the worst condition. Do not try to shot blast yourself. A good shot blasting company will charge .30-.50 cents a sf. Just be informed that shot blasting will more often then not cause what we call lawnmower lines in the epoxy finish. As the shot blasting machine overlaps each strip the tiny pits in the overlapped areas are deeper then the non overlapped pits. So when you apply any epoxy coating over it the deeper pits have more pigment in them and show up as dark lines in the epoxy. Shot blasting is great cause it's inexpensive and fast but just be aware that if final appearance is of critical importance grinding is the better way to go.
Q: Should I fill in my control or expansion joints?
A: If your floor is fairly new the answer is no. You don't want a crack to show up in the middle of your brand new high gloss epoxy floor! If your floor is older than 10 years it's most likely done settling so you can use our crack and joint compound to fill in control joints(saw cuts). If your joints have a material or wood in them, then they are expansion joints and you need to use our flexible joint compound. Just to let you know that if you just feather the epoxy in and out of the joints it will give the floor some dimension especially if your doing a color chip finish. The sections of finished concrete will look like terrazzo slabs. But if you absolutely cannot bare the sight of lines in your floor then use one of our compounds or a good quality compound you can get locally. Whatever you do please do not use some cheap premixed stuff in a tub from your big box store. It will only crack and chip out of the joints ruining your beautiful finished floor.
Q: My floor is rough and very pitted how can I achieve a nice finish?
A: The two images below are of a floor that had a previous water based epoxy on it that did not fill the pits due to its thinness and was failing prematurely as most water based epoxies do. The owner decided to redo the floor with our Ultra Military System. After prepping the floor, he applied one coat of the primer. Then he applied one coat of the high build Lt Blue epoxy with a Flat Squeegee pressing down firmly so that the squeegee pushed material into the pits while leaving a very thin to no coating on the high points of the surface. Next he applied a second coat of the high build epoxy with the notched squeegee and then back rolled it. This completed the filling process and created a thick smooth finish. Final coat was the Military Grade Clear Topcoat for abrasion and wear resistance. Please note that doing these floors is not an exact science as far as knowing exactly how much of the epoxy you will need. Since coverage will vary greatly depending on the severity of the pitting. We suggest you contact us whenever trying to coat a badly pitted floor.
Q: How difficult is it to apply and how long should it take.
A: Our kits are designed to make it very easy to apply our coatings and achieve a professional looking finish even if you've never done this before. Our Instructions are very detailed and easy to follow. Working times for a typical 2 1/2 car garage are aprox 2 hrs for cleaning and etching, 2 hrs to apply epoxy and chips and 2 hrs to apply topcoats. That's it.
Q: What is the purpose of etching and do I need to power wash my floor?
A: Power washing your floor prior to etching will yield the best results. Etching cleans out ground in residues and opens up the pores of your concrete allowing the epoxy into the concrete forming a permanent bond. Etching should be done after you power wash and the floor is still wet. Please note if your floor is stained with oil & grease you must use a good degreaser to remove these stains. Etching will not remove them and the epoxy will not adhere to stained areas. The ideal condition of your floor should be absolutely clean, dry and have a rough texture to it similar to an emery board when you rub your hand across it. If your floor was polished smooth it may be necessary to etch a second time. You need to etch your floor no matter what size it is and especially if it's brand new. On brand new floors you get a lot of curing residues that float up to the surface. We recommend you do two good etchings and neutralize with TSP powder. If you diamond grind it's not a bad idea to use etching solution during the rinse off. Since the floor is wet you might as well etch it as you are rinsing off the dust from grinding. A power washer works best for doing the rinse off after grinding. Grinding is good for getting down to clean concrete but it's the etching that opens up the pores.
Q: When should I repair the cracks in my floor.
A: If using the crack and joint compound, repair the cracks and let it cure overnight then clean and etch the floor. If using the ready crack repair kit, clean and etch the floor first and let dry, then fill in cracks with repair kit and apply epoxy. You don't have to wait for the ready crack compound to dry. See our Crack Repair Kits HERE See this image of a typical floor crack that was repaired with the Crack & Joint Compound and then ground smooth with a grinder. Also notice the difference between the clean concrete and dirty concrete. This is another example of what your floor should look like prior to applying an epoxy coating to it.
Q: Should I remove all of the old paint off my floor.
A: You should give it a high pressure power wash and scraping to remove as much as possible. If the old coating flakes off from the power washer it means it is not properly bonded to the concrete and you should remove it entirely. If only small portions come off then use our special primer to coat over the remaining coating after you properly prepped it. See the photos below for what your floor should look like. This was a large auto dealership floor that had a typical low grade epoxy on it with a high abrasion loss rating, see our Epoxy Comparison Chart page for an explanation of Abrasion Rating and why it's important that your epoxy has the lowest Abrasion Loss rating possible. The Floor Prep Wheel with 100 grit teeth was used on a buffing machine to prep this floor in a couple of hours. If you are a longtime customer of ours and need to refresh your floor you will need the 25 grit teeth to effectively scuff the topcoat. Small floors can use a standard black pad on a buffer but for larger floors you need the Floor Prep Wheel to get done in a timely manner. Prepping the floor in this fashion and then priming with our special bonding primer will ensure a proper bond between the old coating and our epoxy. See below to purchase one of our Floor Prep Wheels.
Q: Can I coat over a sealer on my floor.A: No. You must remove the sealer entirely. Use a 2 gallons of water to 1 gallon of Muratic acid solution for every 250 square feet of floor to remove the sealer. Sprinkle solution over a wet floor, scrub in and let sit for 5 minutes and rinse off. Do the floor in sections and try to avoid rinsing solution over a previously washed area more than once. This will avoid over etching of your floor. After using Muratic acid sprinkle TSP Powder over the floor after rinsing has been completed and while the floor is still wet. Brush in with stiff bristle shop broom and then rinse off thoroughly this will neutralize the acid in the floor. When done let floor dry and sprinkle water on it, if the water is absorbed into the concrete quickly then the sealer has been removed, if not, repeat the acid washing steps above. If the floor was sealed with a good industrial grade sealer Acid may not be effective. You will need to use either a black pad or our one of our Floor Prep Wheels to remove the sealer.
Q: Whats the best way to apply the chips.
A: Take a small amount of chips and toss them up the air at a 45 degree angle away from you allowing the chips to randomly sprinkle down onto the epoxy. Applying small amounts of chips at a time allows you to gradually fill in the floor in an even pattern for a beautiful finish. Also see the method of using a plastic jug on the main page. In our opinion it doesn't get any better than the customer's floor who came up with that idea.
Q: How long should I let the floor dry after cleaning and etching.
A: We recommend minimum of 24 hrs and preferably 48 hrs. You don't want any hidden moisture in the floor when you apply the epoxy coating to it. It will lead to spot failures some time in the future and you will be scratching your head why.
Q: Can I apply the epoxy out past my garage door.
A: We recommend that you stop inside the door but if you go 1-3" past the door its ok but we can't guarantee it. The constant exposure to the sun and elements will eventually cause damage to the high gloss finish.
Q: I purchased the upgraded military grade topcoat, do I still to do two coats
A: No. You only need to do one coat with the military grade topcoat. Two coats are not necessary and we actually recommend against it. The military grade topcoat is a super hard nonstick finish. Nothing likes sticking to it, not even itself. If you have to do two coats then you need to sand in between coats to make sure they bond together. But that should be the rare exception, one coat is like liquid steel on your floor. If you happen to wear it out then you can apply a new coat at that time.
Q: Can I apply the epoxy and chips to the curbing around my perimeter walls.
A: Yes. You can brush on the epoxy to the curbs and then apply the chips. You should do your curbing first, then the floor. When doing perimeter curbs please allow an extra margin of safety material wise since curbing typically absorbs more paint than the floor. You can sprinkle a line of chips on the floor and kind of puff them up onto the curb with a leaf blower. Several customers have told us this method worked great for them.