Remove burn marks from concrete by using washing soda and water, or a homemade alkaline cleaner containing washing soda, borax, dish soap and water. Strong chemicals such as acid-based cleaners may etch or otherwise damage the concrete.
Simple Spot Treatment
Things You'll Need
Wet the burn mark with a little water.
Mix a little water into some washing soda in a shallow bowl to make a paste. Make more than enough paste to cover the burn mark.
Pour the washing soda paste over the burned area. Scrub the spot with a scrub brush while wearing rubber gloves.
Rinse the area after several minutes using a garden hose or bucket of water.
If the stain remains, apply washing soda directly to the wet burn mark, allowing it to sit for 10 minutes or longer. Scrub the area. If the stain remains, apply the paste again and allow it to sit until it dries completely. It may take several attempts to completely remove the stain.
Homemade Alkaline Cleaner
If the concrete suffers from a number of burn spots, mix up your own that is also good at removing dirt and oily or greasy spots. An alkaline cleaner has powerful detergent properties that can remove stains while also neutralizing acidic substances that cause stains.
Things You'll Need
Hot tap water
Liquid dish soap
Add one gallon of hot tap water to a bucket. Mix in 1/2 cup each of borax and washing soda, followed by a tablespoon of liquid dish soap. Scrub the affected concrete with the solution using a stiff-bristled scrub brush or push broom. Hose or rinse the concrete afterwards.
Both washing soda and borax can be found in the laundry detergent aisle in large grocery stores or big-box stores.
- Wear rubber gloves when working with washing soda and avoid getting it in or near your eyes. Rinse off skin that comes into contact with the washing soda, as the soda may cause irritation.
- Do not use acid-based cleaners or harsh chemicals on concrete, as they may etch the surface.
- If the stain is on a countertop, interior floor or other highly finished, sealed or colored concrete surface, consult your concrete installer for recommendations before using any cleaning method.
Kathy Adams is an award-winning writer. She is an avid DIYer that is equally at home repurposing random objects into new, useful creations as she is at supporting community gardening efforts and writing about healthy alternatives to household chemicals. She's written numerous DIY articles for paint and decor companies, as well as for Black + Decker, Hunker, SFGate, Landlordology and others.