The short answer
Seal when the concrete is in good condition and you want to protect it against water, oil, salt and stains without changing much how it looks: driveways, walkways and patios. Coat when you want color, grip, a surface that resists hot tires and chemicals, or to cover a slab that looks worn: garages, workshops, pool decks and commercial floors. Coatings run from about $5 per square foot depending on the system, estimated; sealing is quoted after seeing the surface.
What a sealer does
A sealer is a protective product. Penetrating sealers soak into the concrete and repel water from inside, without changing the look or making it slippery. Film-forming sealers stay on the surface, give a wet look or a sheen and bring out color. Neither one adds real thickness, covers damage or changes the color much. See concrete sealing.
What a coating does
A coating, such as epoxy with flakes or an exterior pool deck system, is a new surface bonded to ground concrete. It adds color and texture, resists hot tires, oil and many chemicals, covers stains and small imperfections and gives grip where it is needed. It takes more preparation and costs more.
Side by side
| Sealer | Coating | |
|---|---|---|
| Changes the look | Little or none | Completely |
| Covers stains and wear | No | Yes |
| Adds grip | Little | Yes, with texture |
| Resists hot tires | No | Yes, with the right system |
| Preparation | Cleaning | Diamond grinding and repairs |
| Cost | Lower | Higher |
Surface by surface
- Driveway in good shape: seal it. A penetrating sealer protects it without making it slippery.
- Garage: coat it. A flake epoxy system handles hot tires, oil and dirt; a sealer will not.
- Patio in good shape: seal it, or coat it if you want color and texture.
- Pool deck: usually a textured, UV-stable coating system. See pool deck coating.
- Balcony with water getting through: neither. It needs waterproofing with a membrane.
Next step
Send us photos of the surface and tell us what bothers you about it. We will tell you whether it needs a sealer, a coating or something else. Coating prices are in the cost guide.
