Concrete & garage floor calculator
Floor coatings cover less per gallon than wall paint — concrete is porous and the formulations are thicker. Pick your coating type and slab dimensions below.
Estimates round up to the nearest quart and are based on Kompozit's published coverage. Buy slightly more for touch-ups and color changes.
Coverage drops on concrete
Bare concrete is porous and absorbs the first coat unevenly. Plan for ~225 sq ft/gal with a proper concrete paint like Kompozit STRONG. Granite-grip and similar anti-slip textured coatings cover even less (75 sq ft/gal) because the formulation includes aggregate that builds the slip-resistant surface.
Prep matters more than the paint
On previously sealed concrete, etch with muriatic acid or use a TSP substitute and rough up the surface. On bare slabs cured 28+ days, sweep clean and pressure-wash. Any oil stain has to come off first — paint won't bond through oil.
Two coats, always
Even concrete paints rated as one-coat want two for hot-tire pickup resistance and uniform appearance. The first coat soaks in unevenly; the second is what you actually see and walk on.
FAQ
No — STRONG is 100% acrylic concrete paint, not a two-part epoxy. It's much easier to apply (no mix pot, no time pressure), holds up to garage and patio use, but isn't appropriate for commercial industrial floors. For DIY garages, driveways, and patios it's the right product.
STRONG is formulated to resist hot tire pickup — the failure mode where tires that have been driven on hot asphalt soften the paint and lift it off when parked. Cheap concrete paints fail at this within a year. Etch the slab properly and apply two coats.
Only if you fix the moisture first. Hydrostatic water vapor coming up through a slab will lift any paint, including STRONG. Tape a 2'×2' plastic sheet to the floor for 24 hours; if there's condensation under it, the slab needs a vapor barrier or sealing before you paint.