You expect bare concrete once you dig into your existing floor, but instead you have some sort of amber colored flake or film on it. Some lines of glue here and there and maybe a red colored primer. All appear to have some good bond to the floor. Can you apply a new floor product over this?
Yes, there are times you can leave it on. You just have to know what it is, whether it’s properly adhered, and whether the floor system you are using allows it. Primer and old adhesive are not the same thing. Using them as an equivalent could result in your new floor being adhered to something that failed previously.
What About the Unknown Film/Layer?
There are many things that can leave a colored residue on your concrete. It could be primer or maybe it was another product. The color and consistency of what you’re dealing with doesn’t always give you a true answer. There are areas on your floor that may have looked similar but were primed on different dates.
Check your existing film by seeing if it scrapes off, crumbles to a powder or has any sticky properties. Maybe some areas are starting to let go of the concrete. This can tell you more about whether you have something solid to build on top of.
If it is letting go of your concrete, then you want to remove that. Placing a new product over it will not adhere any better to your floor. Custom Concrete Prep & Polish mentions that you need to have a sound surface to build a new product on.
Old Primer?
If it’s a good, solid primer that is adhered to the floor, you may be able to place your new product over it. Depending on your floor system and what your new product is made of, primer is only so durable and what type of primer was used is important to know. There are primers that are meant to be used under certain leveling compounds and not over your new epoxy floor.
Some floor coatings allow you to recoat over existing resin floors if it’s within a certain time period. Sherwin-Williams allows their existing resin floor to be recoated with a specific primer if it’s been ground. This may or may not apply to your situation if your current floor is an unknown primer.
Once you can identify what product you currently have on your floor you can see if it’s compatible with your new floor system. Or simply remove it.
What About Adhesive Film?
Removing carpet, vinyl or tile can leave a large amount of adhesive behind. After you grind away the ridges of glue there can still be a thin layer that’s stuck to your concrete. This can make it difficult to get a new product to adhere to your concrete if it’s placed over the adhesive.
Custom Concrete Prep & Polish offers glue removal on their website for concrete coating. They know that glue can affect your new floor and want it removed before placing any new coating or finish on your floor. :chatgpt-content-reference{index=”2″}
You may be able to use certain underlayment products over an adhered glue film that isn’t water soluble. It will depend on what product you are placing on top of the glue film. ARDEX mentions using their primer over glued down flooring that meets certain criteria.
More Than Just Testing For Glue
When applying your new floor you want to make sure everything underneath it is free of oils, dust, sealer and any other contaminants that could cause your new product to not adhere. You also want to know if the concrete is strong enough to support your new floor system. Sherwin-Williams mentions testing for compatibility when applying new coats of flooring.
Always know what you’re working with and follow your manufacturer’s specifications when deciding whether to leave an old floor on or not. Grinding or Shot blasting your floor can give you a good surface to work with. If there is no need to remove your existing floor don’t waste your time doing so.
Conclusion
By knowing what you’re working with, you can decide whether to remove your current floor or leave it on. Once you know what you are placing over your old primer/glue film, you can look into the best way to prep your floor for a new application. Custom Concrete Prep & Polish can help with any of your concrete needs in the Denver area. Contact us today to learn more.
