Worked case: a one-car solid-color epoxy garage with old paint ground off in an older tract — what happens and what it costs

The scenario

Picture a one-car garage in a house from the 1990s, about 12 by 20 feet, 240 square feet. A previous owner rolled on a gray floor paint that is lifting in sheets near the door and under the tires, and a scrape with a putty knife takes off a strip the size of a hand. The slab beneath has some oil stains, a few hairline cracks and a patched corner.

The current owner uses the garage as a workshop and a bike store. They do not need decoration. They want a plain surface that sweeps clean and does not peel, and they want it for a modest budget.

The starting conditions at a glance:

• Size: one-car garage, about 240 square feet
• Slab: about thirty years old, old floor paint peeling, oil stains, hairline cracks
• System: solid-color epoxy with grit in the top coat
• Setting: a tract-home garage in an older Murrieta neighborhood, July and August mean highs near 91°F

What the job involves

1. The installer scrapes the paint at three spots, notes that it lifts, and prices the removal as a separate line.
2. The owner moves the bench and bikes out of the garage and back, a flat line he or she can handle.
3. A diamond grinder with a dust shroud and a vacuum takes off the old paint in several passes; the oil stains are degreased and ground again.
4. Cracks are routed, filled and ground flush; the patched corner is checked for hollow spots.
5. A primer and a pigmented epoxy build coat are rolled on an early morning; a clear top coat with fine grit follows for texture.
6. The data sheet sets the day for foot traffic and the day the bikes and cars return.

Materials and prep

• Floor grinder with diamond segments, dust shroud and a vacuum, plus a hand grinder for the edges
• Degreaser, patching compound and crack filler
• Primer, pigmented epoxy build coat and a clear top coat with fine grit
• Roller covers, squeegee, cleated shoes and box fans

Add-ons often paired with this job

• Coat the stem wall (the low wall around the garage) — +$150–$400. Not typical for a small one-car bay, but the low wall at the door can be wrapped.
• Extra crack or joint repair (many cracks) — +$100–$300. If the cracks multiply under the paint, a separate flat line pays for the extra routing.

Why it is done this way

Solid color at $4–$7 per square foot is the plain, honest choice for a workshop. It costs less than flake at $6–$9, and it makes no promise to hide anything; with the grit in the top coat it gives some grip, and a heavier grit grips more and is harder to clean.

The old-coating line is the part of the quote this owner has not seen yet. Removing peeling paint costs $2–$5 per square foot, which on 240 square feet is $480–$1,200 and nearly doubles the base. It is a line worth asking for separately, because a quote with no removal line over a peeling floor is a quote that expects the new coating to hold on a weak layer.

The small area has a quirk: small jobs often carry a higher per-square-foot cost, because the setup, the grinder and the crew time do not shrink with the room. The estimator range already reflects a typical small garage, but a real quote can land on the high side.

Heat is a footnote here, because a one-car bay is quick to coat. The installer still starts early, and the door stays open for ventilation.

The alternatives that were weighed and set aside:

• A DIY kit is covered in the DIY guide; it asks for the same removal and a rented grinder.
• Flake at $6–$9 would hide the crack repairs and cost more.

What would change the price

• Paint over a mastic or an old tile adhesive calls for testing before any grinding; this can change the plan and the cost.
• A slab that tests damp adds the damp-slab line of $2–$4 per square foot.
• Fewer than a few cracks lowers the repair time; many cracks adds the flat extra-crack line.
• A tighter budget can drop the grit, which makes the floor easier to clean and slipperier when wet.
• Moving the contents is a flat line the owner can take on.