How Thick Should Epoxy Floor Coatings Be? By Jimmy McGhee

How Thick Should Epoxy Floor Coatings Be?

There are several ways to describe a coating thickness. One version is to use a “mil thickness”. 1 mil is the same as 1/1000th 1 inch (also written as 0.001”). Most human hair is 1 mil. Do not get mil thickness confused with millimeters because 1mm (millimeter) is roughly 39.4 mils. The second type of measurement is easier to understand: coverage rating. To help installers better understand how thick a product should be applied, Versatile Building Products has taken the time to convert the proper ideal mil thickness range into floor coverage. This is done by assessing the optimal floor coating thickness in conjunction with container size. This procedure helps the installer know exactly how much material is needed when they measure out the area of substrate to be coated.

Epoxy Primers

Epoxy Primer coats serve three purposes; excellent bonding, sealing the concrete and providing an optimal surface for the next coat. They provide amazing adhesion with the concrete by anchoring into the pores and microscopic imperfections on the prepared substrate. Epoxy primers only need to be thick enough to serve that purpose.

Moisture Vapor Barriers

Some concrete substrates have high MVE (moisture vapor emissions) which could cause an epoxy floor to fail over time. The solution to this problem is with the use of moisture vapor barrier primers. These products wick deep into the concrete to seal off areas where water can escape. These primers work better when applied slightly thicker.

Epoxy Topcoats

Epoxy topcoats are designed to have self‐leveling properties. This allows them to be applied fairly thick. Thicker applications tend to lay down and dry to a glass‐like finish. Take caution when rolling these out because an aggressive application could induce air bubbles. Also know that thicker epoxy flooring applications tend to have faster dry times.

Polyurethane, Polyurea and Polyaspartic coatings

These are usually the final coat in the floor coating process. They provide amazing clarity and great chemical/scratch resistance. These coatings are also UV resistant and do not turn yellow over time. Polyurethane products must also be applied very thin. Polyurea and polyaspartics can be applied slightly thicker depending upon the application. Too thick of an application with a polyurethane, polyurea or polyaspartic coating may not allow the reaction to release carbon dioxide gas in a timely manner. Several thin coats should be performed rather than 1 thick coat if a higher build coating is desired.