How to Remove Rust Stains From Pavers and Concrete

Orange or brown stains on a driveway, paver patio or pool deck are almost always rust. They are one of the most common complaints from Florida homeowners, and they do not wash off with plain water or a pressure washer.

What causes rust stains?

• Well water sprinklers. Florida well water is often high in iron. Every time the sprinklers hit the pavers, a little iron is left behind and turns orange in the sun.
• Fertilizer. Many lawn fertilizers contain iron. Granules that bounce onto concrete leave small orange dots.
• Metal furniture, grills and planters. Rust drips from legs and bases.
• Rebar or metal in the concrete close to the surface, which shows as stains that come back.

Why pressure washing alone does not work

Rust is a chemical stain bonded into the pores of the surface. Water and pressure cannot dissolve it. Too much pressure can even etch the concrete and make the stain look worse.

How to remove rust stains

1. Test first. Try any cleaner on a small hidden spot, especially on colored pavers and stamped concrete.
2. Use a rust remover made for masonry. Look for products based on oxalic acid or similar mild acids, made for concrete and pavers. Avoid strong hydrochloric (muriatic) acid on pavers: it can etch the surface and change the color.
3. Apply and wait. Spread it evenly over the stain and keep it wet for the time on the label.
4. Scrub lightly and rinse well. Rinse plants nearby too.
5. Repeat if needed. Old, deep stains can take two or three rounds.

Protect your work: seal after cleaning

A good sealer makes it much harder for new rust and other stains to soak in. Once the surface is clean and dry, sealing is the best way to keep it that way.

How to stop rust from coming back

• Adjust sprinkler heads so they water the lawn, not the driveway.
• Ask about an iron filter or a rust inhibitor for your well system.
• Sweep fertilizer off hard surfaces right away, before it gets wet.
• Put pads under metal furniture and planters.

Frequently asked questions

Will bleach remove rust stains?

No. Bleach removes mold and mildew, not rust. It can even set some stains.

Can rust stains come back after cleaning?

Yes, if the source is still there. Fix the sprinklers or fertilizer habit first, then clean and seal.

Find rust removers and sealers in the CSI Store, or post your job and let a local cleaning pro handle the stains and sealing.