I am always getting the question “How many floor finish coats do I need to properly protect floors?”
I have always used 4-6 coats as my standard answer. This comes from experience and the manufactures guidelines.
Since I grew up in Missouri and the “Show Me” principle runs through my blood, I thought I would do a little experimenting to find out if I really knew what I was talking about and find out how many floor finish coats were really needed.
Floor Finish Experiment – How Many Floor Finish Coats Are Needed?
Using a USB microscope, a piece of vinyl floor tile (VCT) and a 20% solids floor finish, I set out to take a look at what is going on at the floor level when applying floor finish. Over the years, I have applied countless layers of floor finish. While I have learned to recognize when a floor is properly protected, I wanted to see it up close.
Here Is How I Did It
First I took a new piece of VCT and stripped it using a standard, no rinse floor stripper. I did this by applying the stripper, allowing it to set and then scrubbing with the center of a black floor pad. I then rinsed the tile and allowed it to dry.
Then I took tape and divided the tile into 6 sections and applied a coat of 20% solids floor finish to the entire tile. Allowed it to dry for 30 minutes and then repeated the steps, excluding one section each time I applying additional floor finish coats. Here is what I came up with once the process was complete. (These images were taken at approx. 400x magnification.)
Step 2 – Apply 1 Floor Finish Coat
Step 3 – Apply 2nd Layer of Floor Finish
Step 4 – Apply 3rd Layer of Floor Finish
Step 5 – Apply 4th Layer of Floor Finish
Step 6 – Apply 5th Layer of Floor Finish
Step 7 – Apply 6th and Final Layer of Floor Finish
Analysis and Conclusion
As you can see, there is very little difference between the first and 3rd coat. Once you get to the 4th application, the floor finish really starts to build and show depth.
Since protection is what applying floor finish is all about, I would have to say that a minimum of 4 coats are needed to fill the areas of the floor that would be able to hold dirt and residue. This also where you begin seeing the gloss and shine on the tile.
This helps to answer the question “How many floor finish coats do I need to use.” This of course depends on the type of finish and the floor, but at the minimum, it is a starting point. I don’t think I would ever go to the effort refinishing a floor without applying 6 coats. It is just too much work to not make sure it’s done right.
I have applied more on jobs over the years, but after 6-8 there isn’t much added shine. The number of floor finish coats can determine the longevity of the re-coating cycle, but too many can also be costly.
I would love to hear your thoughts. Let me know in the comments how many floor finish coats you think is right.