Applying Epoxy Floor Paint – The Top 5 Common Mistakes to Avoid!

Applying Epoxy Floor Paint – The Top 5 Common Mistakes to Avoid!

Want to get it right when applying epoxy floor paint? If you are looking at carrying out a DIY garage floor epoxy installation, you may wish to consider this ESSENTIAL CHECKLIST in order to avoid the most frequently occurring errors made by people when applying a floor paint in a garage setting.  These 5 mistakes represent around 95% of all issues frequently associated with either the failure of epoxy floor projects or unsuccessful garage floor appearance.

People frequently apply their own garage floor coatings, often with considerable success.  When embarking on floor paint applications, home owners imagine the end result and anticipate the improvement in appearance it will make to their home. After all the expectation, you owe it to yourself to avoid the disappointment when a project falls short of the imagined results. We have years experience in the floor paint industry and are happy to provide our advice on what to watch out for when applying epoxy floor paint.

So here is our list of common epoxy installation mistakes…

1 – Poor Floor Preparation

Insufficient or inadequate floor preparation is the number 1 reason by a long way for epoxy floor failures and/or poor floor appearance.  Often, when installing an epoxy garage floor coating for the first time, people fail to understand how significant the correct preparation of the concrete is.  Correct floor preparation involves so much more than simply making sure it is clean. One of the reasons for this is that epoxy floor paint will not adhere to an overly smooth surface (i.e. powerfloated).

So, in addition to the requirement that the garage floor must be free of all oils, waxes, and other contaminants, the “concrete pores” on the surface of the concrete need to be properly opened up.  This step frequently involves acid etching at the very least minimum, using products such as Clean n Etch.  Mechanical grinding the concrete in preparation for the application of epoxy is even more effective, but this isn’t always a practical option for the typical homeowner.

The most commonly occurring problem resulting from poor floor preparation is peeling or “delamination” of the epoxy floor paint.

Fisheyes are another problem – these surface problems result in a circle in the finish which resembling a fisheye, hence the name. Fisheyes are created by contaminants in the floor, such as grease or oil. This causes the epoxy floor paint to pull away from the concrete while curing is taking place.

Despite what many people assume, a new garage floor actually requires the same amount of preparation as one that is 10 or 15 years old.

2 – Moisture in the Concrete

This common mistake usually happens as a consequence of not allowing concrete to dry sufficiently after acid etching.  Dependant on the humidity and temperature, you should allow for a minimum of 24 hours and sometimes longer in order for the concrete to properly dry.  If you don’t do this, the moisture that remains trapped in the concrete pores will rise to the surface and then create bubbles, spoiling the garage floor finish.

You may want to set about applying epoxy floor paint when the concrete floor is not fully dry. Whilst it is true that some water based epoxies and primers allow for application to concrete that may still be damp, please contact us for advice on which products would be most suitable in these circumstances.

Not carrying out a moisture test is another common mistake.  It is possible that moisture under the slab can result in hydrostatic pressure. This problem will actually cause the epoxy to separate from the surface. This can sometimes lead to pieces of concrete coming up with it.  In order to avoid this problem by doing a simple moisture test first to determine if your floor is suitable for applying epoxy floor paint.

3 – Stretching out the Epoxy

Trying to reduce the costs of a job by stretching out the epoxy when you are running low will result in areas with a far less glossy surface with a clear difference in color appearance, as well as a weaker coating, so DON’T DO IT!

As an example, you may have purchased a kit that has a stated coverage rate of 300-400sf².  If you have a 400sf² garage floor, you may well run short of epoxy floor paint.  The reason for this is that a properly prepared floor is porous – it will absorb some of the coating and you will therefore run short (and perhaps be tempted to try stretching out the epoxy).

Manufacturers sometimes state in their fine print that you can realistically expect around 15% material loss due to product left in the container and first coat applications.  Most DIY installers fail to read the small print and are simply unaware of this issue.  This problem can be easily avoided by not underestimating the amount of epoxy resin floor paint that you require. We would recommend not using a paint tray as firstly you will lose valuable product and secondly, residue will remain in the tray resulting in different ages of epoxy being mixed together. Finally, it is a time wasting step and time is of the essence when applying epoxy.

Finally, when pouring the freshly mixed batch of epoxy onto the garage floor, don’t scrape or try to get every last drop from the container in order to get the best coverage rate.  This is because the very bottom and sides of the pot are never fully mixed.  If you do try to get every last drop while applying epoxy floor paint, you may find that you will end up with spotty areas of the coating that will remain soft and will not harden properly.

4 – Faulty Mixing of the Epoxy Floor Paint

Many problems can result from faulty mixing.  The most frequently occurring of these issues leads from mixing too fast with a paddle mixer. Doing this can lead to trapping air in the epoxy mixture. Fast mixing results in air bubbles in the surface created during application.  This issue can easily be avoided by not pumping the paddle mixer up and down or stirring the mixer too rapidly near the surface as this creates a vortex and sucks in air.

You also need to make sure that you mix Part A resin and Part B hardener correctly and that you get the ratios correct by paying close attention to the mixing instructions.  Before applying epoxy floor paint, you need to let the newly mixed batch sit for a specific time, approximately 10 minutes, called the “induction time” before application.  Failure to do this can mean that the epoxy might not cure and harden properly.

5 – Failure to follow the temperature and humidity restrictions

Be sure to follow the manufacturer’s recommended instructions for temperature and humidity.  Applying epoxy floor paint at low temperatures below those recommended by the manufacturers instructions can lead to a floor installation that may not cure and harden properly.

At the opposite end of the spectrum, applying epoxy in a hot environment can mean that time available to apply the epoxy can be reduced by half or even more.  His temperatures can make epoxy floor paint virtually unworkable before it is all applied as well as creating bubbles from “outgassing” due to the high temperatures.

Finally, high humidity levels can lead to a microscopic layer of moisture forming at the surface of the concrete that is not visible to the naked eye.  This invisible layer will cause adhesion issues which in turn can lead to delamination or peeling of the epoxy.  High humidity levels can also cause some epoxies to blush at the surface.

Final Thoughts on Applying Epoxy Floor Paint

With all these warnings in mind it is easy to think that applying epoxy floor paint is fraught with risk. In reality, achieving a successful floor coating isn’t particularly difficult and most of these epoxy application errors can very easily be avoided by properly reading and sticking to the instructions.  If you are in doubt, about any of these aspects of garage floor preparation, please contact us. If you research your project properly, put the time in to proper surface preparation and familiarise yourself with the manufacturer’s instructions, you will avoid these common mistakes and end up applying epoxy floor paint like a professional!