100% solids epoxy is a two-part epoxy with no water or solvents that evaporate as it cures. Nearly everything applied stays on the floor, so it builds thick layers per coat. It’s the standard for heavy-duty floor coating base coats, and it has low odor compared with solvent-based products.
What 100% Solids Epoxy Means
“Solids” is the part of a coating that’s left on the floor once it cures. Many floor paints are part water or solvent, and that part evaporates as they dry, so the film shrinks and ends up thinner than what went on. A 100% solids epoxy has no added solvents or water to evaporate, so it cures into a solid with far less shrinkage.
Think of it like the difference between a glass of fruit juice and a glass of ice. Leave the juice out and most of it evaporates, leaving a sticky film. Freeze the ice and you still have a full glass. A 100% solids coating is the full glass.
Why 100% Solids Epoxy Matters for Your Floor
Thickness is a big part of what makes a coated floor last. A thicker layer can soak up more scuffs, dropped tools, and car traffic before wear shows through, and it helps smooth over small dips and pits in the concrete. Thicker systems also tend to hold up longer.
That’s why many professional floor systems use 100% solids epoxy for the primer/base coat, the layer that grips the concrete and carries the color or flakes. A tougher topcoat usually goes over it to handle sunlight and daily wear.
100% Solids Epoxy vs. Water-Based and Solvent-Based Epoxy
You’ll see three kinds of two-part epoxy on quotes and store shelves:
- 100% solids: Nothing evaporates, so what goes down stays down.
- Water-based: Part of what’s in the can is water that dries off, leaving a thinner layer.
- Solvent-based: Part of what’s in the can is solvent that evaporates, also leaving a thinner layer.
Each type has its own handling quirks, and products vary a lot by brand. Ask your installer which type they use for each coat, how thick the finished system will be, and why they chose it for your floor.
For a wider look at coating options, see our guide to concrete floor coatings.
100% Solids Epoxy FAQ
What does 100% solids epoxy mean?
It means the epoxy has no water or solvent that evaporates while it cures. What gets spread on the floor is what stays there, so the coating doesn’t shrink and builds a thick layer in one coat.
Which is better, water-based or 100% solids epoxy?
For a garage or basement floor that sees real use, 100% solids is usually the stronger choice because it lays down much more material per coat. Water-based epoxy is common in DIY kits, but part of it dries off, so each coat leaves less material behind. Ask your installer how thick the finished floor will be.
Is 100% solids epoxy waterproof?
Cured epoxy is very good at stopping moisture from passing through, which makes it easy to clean and hard to stain. That same trait can be a problem on a damp slab, because moisture trapped underneath can push the coating loose. Have your contractor test the slab for moisture first.