Concrete may be tough, but it’s not stain-proof. Whether it’s an oil spill on your driveway, rust from garden tools, or mildew on your patio, concrete stains can quickly turn a clean surface into an eyesore. The good news? With the right tools and knowledge, you can tackle almost any concrete stain effectively.
In this guide, we’ll show you how to clean stains on concrete step-by-step. We’ll also help you choose the best method based on the stain type and whether you’re dealing with outdoor driveways or indoor garage floors. Plus, if a DIY clean-up doesn’t cut it, we’ll explain when it’s best to call in the pros for expert concrete cleaning in Hobart and across Australia.
Why Concrete Stains Happen
Concrete is a naturally porous material, meaning it readily absorbs liquids such as oil, grease, paint, and even rust. Over time, these substances can seep beneath the surface, leading to stubborn stains, discolouration, and in some cases, surface damage.
Common culprits include oil and grease from cars or BBQs, paint splashes during renovations, rust from metal tools or furniture, mold and mildew in damp, shaded areas, and organic messes like pet urine, fallen leaves, or mud. Knowing what type of stain you’re dealing with is the crucial first step to choosing the right cleaning method and restoring your concrete.
Tools & Products You Might Need
Having the right tools on hand makes concrete cleaning safer, easier, and more effective, especially when dealing with stubborn stains or large outdoor areas.
- Broom or leaf blower to clear loose dirt and debris
- Bucket and mop for general cleaning or mopping indoor surfaces
- Pressure washer that is highly effective for deep outdoor cleaning
- Degreaser or dish soap, ideal for oily stains
- Concrete cleaner i.e. alkaline or acidic, depending on the stain
- Stiff-bristled brush for scrubbing tough spots
- White vinegar or baking soda for natural cleaning
- Protective gloves and eyewear for safety, especially when using chemicals
General Concrete Cleaning (Routine Maintenance)
For patios, driveways, or garage floors that collect everyday messes like dust, foot traffic grime, BBQ drips, or car leaks, a basic cleaning routine goes a long way. Regular sweeping and occasional scrubbing with soapy water or pressure washing helps prevent stains from setting in and keeps the area looking clean and safe for daily use.
- Sweep the area to remove dust and leaves.
- Pre-treat stains with dish soap or degreaser.
- Pressure wash the surface using a fan tip (if outdoors).
- Rinse thoroughly with a hose or bucket of clean water.
How to Remove Common Concrete Stains
How to Remove Oil Stains from Concrete
Oil stains from cars or BBQs can soak deep into concrete, especially if left untreated. Quick action is key for fresh spills, but older stains may need stronger treatments.
- 1.Blot the area with paper towels.
- 2. Sprinkle kitty litter or baking soda to absorb residue. Leave for 30–60 minutes.
- 3. Scrub with degreaser or CLR Oil & Grease Remover.
- 4. Pressure wash or rinse with a garden hose.
For old oil stains, use a paste made of acetone and talcum powder, let it sit overnight, then scrub.
How to Clean Paint from Concrete
Paint spills from home projects can be tricky, especially once they dry. Acting quickly and using the right products helps lift the stain without damaging the concrete.
- 1. Mix 1 cup of TSP (trisodium phosphate) in a gallon of hot water.
- 2. Apply to stain and let it soak for 30 minutes.
- 3. Scrub with a nylon brush, then rinse.
- 4. Use a paint stripper for dried or stubborn paint. Always wear gloves and goggles.
Safety Note: Avoid steel wool or wire brushes, they can damage the surface.
How to Get Rust Stains Out of Concrete
Rust stains often come from metal furniture, tools, or garden equipment left on damp concrete. These orange marks can be unsightly but are usually treatable with common household or commercial products.
- 1. For fresh rust, pour white vinegar directly on the stain. Let it sit for 10–15 mins.
- 2. Scrub with a brush, rinse, and repeat.
- 3. For tougher stains, use oxalic acid or CLR Rust Remover.
How to Clean Mould and Mildew from Concrete
Mould and mildew thrive in damp, shaded areas like patios, pathways, or basement floors. If left untreated, they can create health risks and slippery surfaces.
- 1. Mix 1 part bleach with 4 parts water.
- 2.Apply using a mop or spray bottle.
- 3. Let it sit for 10 minutes, then scrub with a brush.
- 4. Rinse well and let dry.
For eco-friendly options, use white vinegar or baking soda paste instead of bleach.
Can You Use a Pressure Washer on Concrete?
Thinking of blasting away grime with a pressure washer? It’s a powerful way to clean concrete, but only if done correctly. Using the wrong pressure or nozzle can leave permanent marks or even damage the surface.
To do it right, always choose a fan spray tip to evenly distribute the pressure and avoid etching. Keep the pressure below 3000 PSI, and use overlapping passes for a streak-free finish. For exposed aggregate concrete, it’s best to start with a garden hose and only move to pressure washing if necessary, using the lowest setting that gets the job done.
When to Seal Concrete?
Sealing concrete after a thorough cleaning is essential for long-term protection. It helps prevent future stains from oil, grease, or spills, and also reduces the risk of mold and mildew growth, especially in damp or shaded areas.
A properly sealed surface is easier to clean, looks better over time, and can significantly extend the lifespan of your concrete. Not sure if it’s time to reseal? Just pour a little water on the surface, if it soaks in instead of beading up, your concrete is ready for a fresh coat of sealer.
FAQs
How do you remove old oil stains from concrete?
Use a degreaser or make a poultice with acetone and talcum powder. Let it sit overnight, scrub, and rinse.
What is the best cleaner for concrete driveways?
Commercial concrete cleaners or degreasers, plus a pressure washer, work best.
Can I use bleach to clean concrete?
Yes, but avoid it on sealed surfaces. Always dilute bleach and rinse thoroughly.
What removes rust stains naturally?
White vinegar works well for fresh stains. Use a commercial remover for tough rust.
Is pressure washing safe for concrete?
Yes, if used correctly. Avoid too much pressure, and test in a small area first.
Conclusion
Knowing how to clean stains on concrete the right way saves you time, money, and stress. Whether it’s everyday grime or stubborn oil spills, treating the stain properly makes all the difference. From patios to driveways, these tips will keep your concrete surfaces looking great for years.
And when DIY isn’t enough, our team is here to help. We offer professional concrete cleaning, sealing, and repair services across Hobart and the surrounding areas. Contact us today for expert results that last.
