Hi Gary. Unfortunately, the SikaFlex should be removed. Coatings will not adhere to it. In addition, it has too much flex and can cause a coating to crack if enough pressure is applied to the joint. You can run the coating up to the joint if you tape it off. The issue is that it gets a bit tricky because you need to remove the tape before the coating sets too much and becomes part of the coating. You can’t wait for it to cure like paint on a wall. Accessing the tape at all the joints while the coating is still soft also presents issues. If you remove the SikaFlex, you can use other compatible materials to fill the joint and create a seamless look. We have an article on it here.

Thank you Shea !!

One more item. I previously filled the contraction joints with Sika Self Leveling Sealant, which does have flexibile properties.
* Can any of the recommended primers, coatings, clear coats be applied over the joint
* Or should the Sika be removed, if possible and then the layers applied
* Or should the layers be run up to the edge of the joint

Thank you,
Gary

Hi Gary. The first item to address, since you live in Florida, is possible moisture vapor transmitting up through the slab. However, since you are going to hire a contractor, they should be able to assess and test for that based on your location.

As for base coats, we prefer 100% solids epoxy when long-term UV exposure is not a concern. There are a few reasons for this. Epoxy cures more slowly than other coatings, allowing it to penetrate deeper and achieve the best mechanical bond. It also provides a 40% to 60% thicker build coat when applied at the proper coverage rates. Because 100% solids epoxy is self-leveling, it does a great job of hiding small concrete imperfections that other coatings can’t hide. This is advantageous on slabs with few to no color flakes. Lastly, it is the most tolerant of concrete moisture, which Florida slabs are famous for, and it has a deeper, wet-looking finish compared to other coatings.

Unfortunately, many concrete coating companies steer customers away from epoxy because they can’t complete a job in one day. This is due to the slower curing time required. Additionally, these companies are often limited to only one product brand, and epoxy isn’t available. They want to apply a polyurea or polyaspartic base coat instead. Beware of the companies that adamantly state epoxy is inferior. These are the same companies that make outrageous and incorrect statements about how inferior epoxy is to the products they are pushing.

That said, there is nothing inherently wrong with polyurea as a base coat, and it adheres just fine when the concrete is properly profiled and the applicators don’t rush the required minimum cure schedule. Just be aware that it won’t achieve the same build thickness as epoxy; it won’t self-level as well, and it won’t look as deep and glossy. If these features aren’t as big a deal to you, there is nothing wrong with choosing polyurea based on your needs.

High-solids polyaspartic is typically the best clear coat to apply. It’s water-clear, UV-stable, highly resistant to most automotive chemicals, and offers the highest scratch and wear resistance. The clear coat is the wear-and-abuse coat, so it needs to perform well. DO NOT use it as a base coat. Polyaspartic is the least tolerant of moisture in a slab and cures so fast that it doesn’t adhere as well to concrete. Steer clear of any installer that tries to tell you otherwise.

Color flakes do not add strength, but they do add impact resistance if applied to full refusal. That is a non-factor if you want light coverage. A light coverage of flakes will not make the floor bumpy either. I recommend adding an anti-slip media to the clear coat. Most are soft enough that you can walk barefoot on the floor, and they won’t snag mops, cloths, etc. during cleanups. Check with the installer about what they use.

Let me know if you have any more questions.

Preferences:
* High durability
* Anti slip OK but not super bumpy
* Flakes OK but not crazy about monster coverage. Do they add to strength ?

Thank you

Hi Jim. Can you provide more information? Is it a bare concrete floor? Do you currently have a coating system? If so, what was used?

Thanks for your feedback.