Coating Vinyl Plank with Polyurethane
Protecting a Low Cost PVC Floor with a High Tech Polymer Finish
The vinyl floor in my kitchen was looking ragged, so I gave it a makeover by bedecking it with grey peel-n-stick plastic planks and then sealing it with a glossy, impenetrable barrier of polyurethane to create an alluring effect.
Walking the plank
While perusing the flooring section of Jerry’s Home Improvement, I noticed a selection of self-adhering, wood-tone PVC planks. Internet blogs advertise how easy they are to install, so I purchased 200 square feet of the slate gray version for about $130.
Floor prep
Following the recommendations of online DIY experts, I cleaned the floor thoroughly, for failure to adhere is usually caused by traces of dirt, oil, dust, or grime. I swept, mopped four times, and followed with Once ‘n Done. To promote adhesion, I applied two treatments of LevelQuik, an acrylic primer.
Peel-n-stick
Coronating my kitchen floor with vinyl planks was fast and easy. Care should be taken when peeling the backing off the planks, because they can rip right in two if too much force is applied. After struggling to make good cuts with a safety knife, I discovered that scissors worked just fine. Although floor adhesive can cause buckling, because the planks already have glue, I sprayed some on anyway.
Voila, success! After rolling with the applicator, some of the planks did indeed bow up, presumably because I had not let the floor adhesive dry tacky before applying.
Although the floor was attractive, I was not totally satisfied. The surface was soft and scuffed easily. The PVC was odoriferous, duller than I had hoped, and seemed to attract dirt even with frequent sweeping. I also worried about water intrusion where there the joints were slightly maligned. I decided I just had to coat with polyurethane.
Molding squared
Molding what? I had not removed the old molding before installing my new floor. Being a chemist and not a craftsman, I tried to find the simplest mechanical route. Using both wood and synthetic molding (easy to cut), a hacksaw, 1-step stain/polyurethane finish, paint, and self-propelled caulk, I managed to ensconce new molding over the old.
Picking the polyurethane
Delving into the chemistry, I deliberated for days over which type of polyurethane to buy, or whether I should use it at all, because applying it over vinyl isn’t typically recommended. Would the polyvinyl chloride surface have enough pores for the polymers to adhere? The planks were textured with hills and valleys, so I had hope. For proof of concept, I purchased a small can of water-based polyurethane by Minwax and performed a spot test with and without primer.
The polyurethane beaded off of the non-treated vinyl, but the Level-Quik treated surface looked great. The primer may have enhanced the available hydroxyl groups for improved bonding of the isocyanate groups in the polyurethane, promoting wetting and bonding. If you are curious about the science behind adhesion promoters, click on the link below.
https://www.sciencedirect.com/topics/chemistry/adhesion-promoter
Since oil-based polyurethane is only for wood and would probably have eaten through the vinyl, I picked an industrial grade, acrylic-catalyzed, water-based polyurethane floor coating from Duraseal with an acrylic cross-linker that needed to be mixed in just before use.
Application
To prep the floor for the polyurethane coating, I cleaned the vinyl with Once ‘n Done and followed with two coats of Level-Quik, allowing for drying in between each step. Since polyurethane reacts with water, I didn’t extend drying times. [Note: Polyurethane is incompatible with the wax found in typical vinyl sealers.] Using appropriate personal protective equipment and ventilation, I used a floor applicator to apply the first layer. The process caused a few bubbles, but those quickly dissipated. On the second night I added another coat and a third the night after.
The new floor
Coating my PVC floor with polyurethane made it look fantastic. The plastic odor is gone. The spaces between the planks are sealed. Spilled liquids bead up and sit on the surface like spheres, allowing for easy cleaning. Chairs slide across the surface of the floor without denting or scratching. Sweeping is a breeze. Months later the floor still looks like brand new. According to research, the coating should last about three years.
Conclusion
Purchasing and installing my new vinyl plank floor was a breeze, but the surface and quality of my floor was improved exponentially after I triple-coated with an industrial grade, acrylic-catalyzed, waterborne polyurethane coating.
Note: I’m sure I voided the warranty of the plank system, but I wouldn’t change a thing. To fix the buckling I stacked my chemistry books on the spots hoping they would learn by osmosis. The floor has since laid completely flat and still resists all sort of spills, including soda, orange juice, slime, and acrylic craft paint.
