A good quality epoxy resin is strong, beautiful, and versatile—the perfect option for a protective finish on numerous different surfaces and decor items. Materials such as granite, quartz, marble, wood, and much more all benefit greatly from an epoxy finish, with improved coloring, greatly enhance resistance to scratching and stains, as well as waterproofing to prevent moisture damage and mold.
However, the application of epoxy, while straightforward, is quite rigid in most cases. If not handled properly, you can end up with a soft, uneven mess.
One of the most common mistakes new epoxy users make—whether because they're unaware or because they didn't follow instructions—is skipping the seal coat of epoxy at the beginning of their project.
What Is a Seal Coat of Epoxy?
An epoxy seal coat is a manually brushed-on layer of epoxy resin, done prior to the flood coat pouring. This is especially important for porous surfaces such as wood. A porous surface is one that contains numerous tiny holes in which air resides.
When epoxy is poured onto a porous surface without a seal coat, it seeps into these pores, pushing out the air, which then tries to surface. But because of how viscous epoxy resin is, some of the air can get trapped within the epoxy finish, appearing as air bubbles.
Seal Coats Greatly Mitigate Air Bubble Formation
To avoid the issue of air bubbles, a seal coat of epoxy is applied to the substrate prior to a flood coat. The seal coat is thin enough that when it seeps into the pores, the air is able to escape. This allows you to pour a flood coat later without worrying about air being released into the finish from a porous substrate.
A seal coat of epoxy is applied using the same resin as your flood coat. For Primaloc users, that will be our premium Bar & Table Top Epoxy. As seal coats are intended to be manually applied as a thinner layer, you'll end up using much less for a seal coat than for your flood coat.
In most cases, a single seal coat is more than adequate. If you're uncertain, however, it's not a problem to add a second one a few hours after the first.
When Do You Apply a Seal Coat of Epoxy?
The epoxy seal coat is applied before anything else, after preparing your surface by cleaning it. It's the first major step of the epoxy application process.
Once you've applied it, you should wait about 4 hours before applying your flood coat. This will give any air time to escape and allow the seal coat to harden a bit.
Note: Sometimes the brush you use will leave behind stroke marks. This isn't a problem. The stroke marks will disappear later once the flood coat is applied.
How Do I Remove Air Bubbles From My Epoxy Flood Coat?
After you pour your flood coat, some air bubbles may be present, even with a seal coat. Typically, this is because the mixing and pouring process of flood coat batches draws in air as it's blended and poured.
You can remove these air bubbles after you finish pouring by using a heat gun or torch. Simply hold the implement several inches away from the surface and quickly move over the entire coated area, doing one complete pass. Don't get too close and don't linger over any spot for more than a second to avoid the possibility of heat damage.
You can learn more about preventing and removing air bubbles in our Primaloc Guide to Air Bubbles.
What Tools Do I Need to Apply a Seal Coat of Epoxy?
There are several supplies you'll need for a seal coat application, most of which you'll also need for your flood coat.
Here's a quick list:
- Primaloc Bar & Table Top Epoxy Resin: Our top-tier resin for all kinds of projects.
- Stir Sticks: You can use wooden stir sticks, or you can try the Poly Pro Reusable Stir Sticks found in our store.
- A Mixing Container: We have a 1-Quart Container in our store that's perfect for seal coat applications.
- A Suitable Paint Brush: The 3-Inch Seal Coat Brush in our store is strong, with firm bristles that are perfect for these applications.
Primaloc's Step-By-Step Guide to Applying Epoxy Seal Coats
Fortunately, applying the seal coat is a straightforward process. Once you have all the necessary supplies for your epoxy project (we recommend you organize them and keep them in a convenient spot), you can begin.
Here's how to apply a seal coat of epoxy:
Measuring a batch of epoxy. For a seal coat, one quart of epoxy will cover 12 square feet. Measure an amount suitable for your project. Primaloc Bar & Table Top Epoxy uses a 1:1 ratio for its resin/hardener components.
We recommend doing no more than 32 oz. at a time, as the time it takes to apply such a quantity starts to become longer than the working time of the epoxy.
If your project requires multiple batches for seal coating, make sure you use a new container with each batch.
Mix the epoxy batch. Using your stir sticks, carefully blend the epoxy components together in the mixing container. This will take a couple minutes. Be sure to scrape the sides and bottom of the container occasionally to prevent any of the resin from stick to the interior surface; this will help ensure a smooth blend.
If any resin does end up sticking to the sides, that's okay. Just don't scrape it out during the application process. You don't want the unmixed component in your coating.
Apply the epoxy seal coat. Use your brush to apply the mixture onto your substrate. Be sure to cover the project surface entirely, to ensure each pore is saturated.
- Wait for four hours. After that, you'll be able to continue with the next phase of your project, typically the flood coat.
Primaloc Epoxy: Premium Epoxy for Premium Results
When it comes to epoxy resin, Primaloc Epoxy gets the job done. Our epoxy resin is premium-grade, with high performance in every category.
Epoxy resin can be beautiful, strong, and long-lasting—which is why you shouldn't compromise on quality. With Primaloc Epoxy Resin, you get the ultimate finish in durability and visual appeal.
Protect your surfaces by giving them a rock-solid epoxy finish. Choose strong. Choose reliable. Choose Primaloc.