Application Tips

This category is where you will find tips on how to avoid mistakes when installing coatings and flooring. We will also discuss how to get around certain problems.

To Grind Or Not To Grind

Grinding is a very good way to get a concrete floor to the right profile for an epoxy coating. Grinding also saves time if you have a good vacuum system that will get all the dust off the floor. You then don’t have to wait for the floor to dry after rinsing and or etching. If you need to rinse the floor down to get rid of all the dust we recommend that you sprinkle some acid etching onto the floor and etch the floor while you are rinsing. Let the etch fizz for 5 or so minutes before you rinse. This way you are cleaning the dust and opening the pores of the slab a little more at the same time.  But the main benefit of grinding is saving the drying time of a wet floor.

The key is to have the right machine for the job which is the main reason for this article. You can read more about grinding in a previous post. But for now we are going to assume you’ve decided to grind. Our advice is to go onto the Blastrac website and contact one of their dealers to rent you the appropriate grinder and vac system. They have locations all over the country. The’re also very knowledgeable and will rent you the right machine for your job. Not too big and not too small.


Above is an image of the proper size machine for a large commercial duty floor. Notice the difference between the grinded areas and the areas that have not been done yet. That is what your concrete needs to look like whether you are grinding or etching, whether your floor is large or small.


Acid Etching Your Floor

Here is a great image of what your floor should look like as you scrub in the acid etching solution to prepare a concrete floor for an epoxy coating.


If  your etch solution does not bubble like this up it means you need a stronger solution and most likely that you need to do a second etch. Also critically important is that it bubbles up over the entire floor and that you scrub the entire floor! It’s easy to miss a spot that could result in what we call a pop. That’s where you get a small piece of the epoxy that just pops up off the floor.  That is easily avoided by taking your time to make sure you don’t miss any spots. Let the etch sit on the floor till it stops fizzing, usually 6-8 minutes. Don’t let the solution dry. You also might want to scrub in some TSP powder right before you rinse. This will neutralize the acid, get the slab to the right PH and do a little extra cleaning all at the same time.

When done your floor should look like new concrete with no dark or dirty spots. You can see a good example here ETCHED FLOOR of what a properly etched floor looks like that is ready for an epoxy coating.

Here is the finished result after applying our Armor II Epoxy System.


This is a floor coating that will last the owner 15-20 years. To get that kind of longevity it’s well worth the extra time to make sure you did a good etching job.

To see the pictures of the whole process and our customer’s comments check out his Facebook page:



What to do about cracks and control joints in your floor

Every concrete floor has or at least should have control joints in them and just about every floor has at least one crack. So lets start with control joints. A control joint is either a saw cut in the slab or a hand trowel groove. They are there to prevent cracks from happening in  your floor as it expands and contracts. If your floor is relatively new(0-5 yrs) it’s not a good idea to fill them in. Especially when coating your floor with a high gloss epoxy. The epoxy will accentuate any crack that does occur and you know that crack will be right in the middle of your brand new epoxy floor.

Leaving the control joints unfilled gives the floor some dimension and the epoxy makes each section look like a large slab of stone if using the chips or a slab of porcelain if not using the chips.  All you need to do for a control joint as far as epoxying it is just feather the epoxy in and out of the joint with your roller. Don’t try to fill it with epoxy, you just want to coat the sides and the bottom of the joint. If using colored flakes, sprinkle the flakes evenly on either side and your control joint will now look like a natural stone joint.


If you’re floor is older and is done settling and you absolutely just can not stand the sight of those lines then you can fill them in with our Crack & Joint Compound. This is a Part A & Part B liquid that you mix with playground sand you buy locally till it becomes a grout like consistency. Then just use a mason trowel to fill in the joint and scrape it smooth. You use a hand grinder to further smoothen it if necessary after it cures. We would fill in the joints, do any grinding if needed to ensure a perfectly smooth finish, then do the clean and etching after.

If your joints have some sort of material in them it means they are expansion joints and not control joints. The same reasons to fill or not fill apply to these. But if you do want to fill them in you need to use a filler that is flexible such as our Flexible Joint Sealer. This will harden enough to accept a coating but stay flexible enough to expand and contract without cracking.

Finally lets talk about cracks. Even though our epoxy is very thick and will fill in small  cracks we recommend you fill in the cracks anyway. Why, because even cracks that appear to be small may run the depth of the slab and filling them in will take lots of liquid epoxy to fill up and if the crack is all the way through the slab it’s a good chance the epoxy will drip out the bottom. So you may think you filled the crack only to find the epoxy sank in overnight. So best just get some of our Ready Coat Crack Filler. You just mix Part A & Part B together, putty knife it into your cracks and divots and then you can apply the epoxy right over it. No need to let it harden for 24 hrs or more like typical crack fillers.  If a crack is just at the surface then you just coat over those. But if it looks like it goes deeper than don’t take a chance, fill it in, it doesn’t pay not to. On smaller cracks you may want to run a grinding wheel down them to V them out a little.

For large cracks, divots and holes use the Crack & Joint Compound mentioned above. What you don’t want to do is use some premixed retail grade filler in a tub or tube. These types of products always fail and will ruin the look of your beautiful floor when they do. If you have access to some quality product that you mix yourself then go right ahead and use it. Just make sure it’s paint compatible.

For other floor issues and repairs visit our Concrete Floor Repair Page. Everything you need to fix your floor is there. In a future post we’ll talk about floor leveling.

Things You Need When Installing an Epoxy Floor

When doing an epoxy floor coating job with any type of epoxy there are certain items you should have on hand. First thing you should have is a cleaner such as Xylene. Xylene is a common cleaner like mineral spirits but it works a little better on good epoxies. If your epoxy is water based then you can use soap and water.

If you are in CA you can buy a Xylene substitute. But in any case you need to have something that will remove the epoxy in case you spill it or splatter it on something you don’t want painted. Especially with our epoxy since once it’s cured it only comes off by mechanical means. So clean up any spills or splatters while the epoxy is still wet. Throw out any rollers, squeegees or mixers right away when your done using them. Good to have a few heavy duty contractor bags on hand or double up your kitchen type garbage bags. When doing a larger floor in a commercial or industrial setting there’s a natural tendency to lean the rollers up against a wall or column or leave the roller sitting in a corner somewhere when your done as you look back and admire your work. Don’t do that, more likely than not you’ll forget about it till the next day when you’ll need a chipping hammer to get it off  whatever you left it on.  We know cause we’ve done it a couple of times ourselves!

Other items you want to pick up at the store before you start your epoxy floor project. Good idea to have a drop cloth to mix the epoxy on, a small plastic one will work best. Some spare latex gloves, they never seem to last long enough. Rags and paper towels are a must. A stiff bristled shop broom for scrubbing the etching solution into the floor.  Thoroughly scrubbing the etc into the floor is key to getting it properly cleaned. Clear measuring containers are a good thing to have so that you pour out accurate amounts of the Part A & Part B of the epoxies. Get containers that are at least 100 ounces or more.

When doing a floor with color chips in it we always recommend you have spiked soles. It’s much easier to get a good even pattern when using spikes. Our Armor Granite kits come with spiked soles. We sell spiked soles separately but you can use an old pair of golf shoes if you have any. We also supply spikes for floor orders over 1500 Sf.

Other items that you will need such as rollers, mixers, squeegees and mixing buckets come with our epoxy kits. All the additional items mentioned above are inexpensive but will go a long way in making the job a lot easier.