Acid stain

Use case

Cured or existing slabs; natural marbled, variegated look

Durability

Very high — cannot peel; palette limited to earthtones

Price band

Mid

How does acid stain work?

Acid stain is a reaction, not a coating, so the slab decides the final color as much as the product does: the same bottle over a rich, hard-troweled floor reads deep and mottled, and over a lean, porous or old slab it barely takes. Test a hidden square foot of the actual slab first, because a sample panel poured last week tells you nothing about a 1978 garage. After the reaction stops you have to neutralize with an ammonia or baking-soda wash and rinse until the residue is gone, or your sealer will not bond and will peel in sheets. The palette is real chemistry rather than a color card: browns, tans, rust reds and a copper green, with no true blues, and every batch varies enough that you should not promise a customer an exact match. Anything sitting on the slab blocks the reaction, so old adhesive, curing compound, power-trowel burnish marks and even drywall mud footprints print through as ghosts.

Screen colors are approximate. Obtain a physical sample from the manufacturer before specifying. Color names and swatch systems are manufacturer trademarks, shown here as editorial reference with a link to the official chart.