Epoxy Primers and Concrete Primers for Floor Coating Systems
An epoxy primer is the layer that connects your slab to everything above it. It bonds the base coat to the concrete, seals porous surfaces, reduces the outgassing that causes bubbles and pinholes, and improves the coverage of every coat that follows. Get the concrete primer right and the system performs. Get it wrong and the best epoxy on the market cannot save the floor.
One Stop Epoxy stocks primers for sound concrete, porous slabs, moisture prone slabs, oil contaminated floors, fast turnaround jobs, and clean surfaces that are not going to be ground at all. Free shipping to the 48 contiguous states, and most orders ship out the same or next business day.
The primer you need is decided by the condition of the slab, not by the floor you want on top of it.
Match Your Slab to the Right Concrete Primer
| What you are working with |
The primer that fits |
Start with |
| Sound, dry, freshly ground concrete |
Standard 100% solids epoxy primer |
LABPOX Primer |
| Porous or thirsty concrete, pinhole or outgassing risk |
Water based pore sealing primer |
One Stop WB Epoxy Primer |
| Elevated moisture, unknown history, or a slab on grade |
Moisture vapor barrier |
LABPOX MVB FAST or One Stop Epoxy MVB
|
| High moisture where the system needs low perm isolation |
Low perm moisture mitigation epoxy |
APF VaporSolve LP |
| Oil stained garage, service bay, or shop floor |
Oil tolerant specialty primer |
APF Oil Stop Primer |
| Properly prepared but damp, mitigation not required |
Water based epoxy approved for damp concrete |
APF Epoxy 100 |
| One day install or a tight return to service schedule |
Fast cure epoxy used as primer or base |
150 Fast Cure |
| Clean, non porous, uncontaminated surface not being ground |
Bonding primer |
Premera Fusion Primer |
| Commercial or industrial floor with chemical exposure |
High performance epoxy primer |
APF Epoxy 600 |
Moisture Vapor Barrier Primers: The One You Cannot Guess At
A standard epoxy primer improves bond. It does not stop vapor. If the slab tested high, has an unknown moisture history, or sits on grade in a humid market, a regular concrete primer is the wrong product and no amount of epoxy on top will fix it. Vapor pushes from underneath and the floor blisters, whitens, or lets go.
LABPOX MVB FAST and One Stop Epoxy MVB are dedicated moisture vapor barriers applied as a functional layer at the required thickness. APF VaporSolve LP handles low perm mitigation on higher moisture slabs. A moisture vapor barrier is not a decorative coat, it is not a thicker primer, and it is not optional when the slab needs one.
Bonding Primer: When the Floor Is Not Being Ground
Grinding is how virtually every professional epoxy floor is prepared, and for good reason. It takes off the smooth shiny crust, opens the pores so the epoxy soaks in, creates the profile, removes surface contaminants, and lets joints be filled and ground flush.
Premera Fusion Primer works differently. It bonds chemically rather than mechanically, so it needs the opposite surface condition: clean, non porous, and free of any contamination. That makes it a real fit in two situations. A homeowner with a sound, clean, uncontaminated slab who is not going to rent a grinder and a concrete vacuum. And a contractor going over a cured urethane or polyaspartic floor that has fallen outside its recoat window, where sanding to a bondable surface costs serious man hours and sheets of sanding screen.
It fits roughly a third of floors. What it does not do is smooth the surface, grind out imperfections in the concrete, or allow the normal process of filling joints and grinding them flush. The contaminants that grinding removes are the same contaminants that rule it out. When the slab is porous, contaminated, or needs any of that work, grind it, and shop concrete grinders and surface preparation equipment for the job.
Epoxy Primer Is Part of the System, Not an Add On
Every epoxy primer here is matched to the epoxy, polyaspartic, flake, and metallic systems we sell, so the layers are compatible before you order. That is the reason for the depth: 18 application specific epoxy formulations (including 6 metallic variants), 7 polyaspartics, and 100+ custom pigments, with the primer path built to match.
Decide the primer before you finalize the rest of the order. If the slab needs a moisture vapor barrier or an oil tolerant path, that changes cost, coverage, and schedule. For mix ratios, coverage rates, and recoat windows, check the TDS for the product you are using.
Not Sure Which Primer Your Slab Needs?
Choosing the Right Epoxy Primer for Your Concrete Floor walks the full decision, including how slab condition changes the answer and how primer choice shifts with the system going on top. If moisture is the open question, start with Moisture Testing Before Installing Epoxy Flooring. If the slab has not been prepped yet, see How to Prepare Concrete for Epoxy Coating.
Frequently Asked Questions About Epoxy Primer
Do I need a primer for my epoxy floor?▾
Many floors do. Primer improves bond, seals porous concrete, reduces outgassing bubbles and pinholes, and increases the coverage of the coats above it. Older, porous, dusty, and moisture prone slabs are the most likely to need one. Skipping it to save money up front is a common false economy.
What is the difference between an epoxy primer and a moisture vapor barrier?▾
A standard epoxy primer improves bond and seals the surface. A moisture vapor barrier does that and controls vapor moving up through the slab. If the concrete tested high or a previous coating blistered or peeled, a standard primer is not enough.
Can I coat over an existing epoxy, urethane, or polyaspartic floor without sanding it?▾
Sometimes. If the existing coating is cured, sound, and completely free of dust, dirt, oil, and grease, Premera Fusion Primer can create a chemical bond without sanding. If the surface is contaminated or the concrete underneath needs work, that becomes a removal and grinding job instead.
Which concrete primer works with 100% solids epoxy?▾
All of these are matched to the systems we sell, including 100% solids epoxy, flake, and metallic builds. The right one depends on your slab condition rather than the base coat above it.
Can I use a regular primer on an oil stained garage floor?▾
No. Standard primers can fisheye, bead, or lose bond on hydrocarbon contamination. Clean, degrease, and mechanically prepare the slab first, then use an oil tolerant primer such as APF Oil Stop Primer.
Can I broadcast flakes directly into primer?▾
Not into a moisture vapor barrier. An MVB has to stay a continuous film, and broadcasting into it breaks that film and reduces the protection. Install the MVB first, then the correct receiver coat, then broadcast.
How much epoxy primer do I need?▾
Coverage depends on the product and how porous the concrete is. A thirsty slab pulls noticeably more than a tight one, and moisture vapor barriers go on much thicker than standard primers, so they cover far less per gallon. Use the TDS, not a generic number.
Do you ship epoxy primer?▾
Yes. Free shipping to the 48 contiguous states, and most orders ship out the same or next business day.