The Efficient Way To Remove Rust Stains From Sidewalks

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A rust-stained sidewalk is a real eyesore, and the longer it persists, despite your stain-removing efforts, the more annoying it gets. You get the stains when metal is exposed to moisture and oxygen on or under the cement. These rust stains can be caused by leaving metal sitting on the sidewalk where it is exposed to moisture, treating your yard with iron, or not dealing with thin or cracked concrete that allows moisture to reach metal underneath the sidewalk. If your rust spots are growing and you haven't left any metal on the sidewalks, then the rust may be from metal in or below the sidewalks, such as rebar to strengthen the concrete. This can damage the structural integrity and surface of the sidewalks and leave you wondering how much a sidewalk repair could cost. Whether you are hoping to prolong the life of your sidewalks or just improve the curb appeal, removing any stubborn stains is important.

If you are tired of trying to get rid of rust stains on concrete with assorted DIY methods, then it may be time to upgrade to a more scientific method. Oxalic acid is an acid that is often used for cleaning because of its ability to dissolve rust. The acid is an odorless, dry white powder or solid made up of crystals. It is not as corrosive as other acids, but it can still be hazardous. It is an irritant, and it can cause severe burns when swallowed or exposed to the skin, so it is important to use it safely and cautiously. With the right preparation, it is an effective way to clean up unsightly rust stains once and for all.

First, you need to source your oxalic acid. If you like to shop in-store, you may be able to find oxalic acid at home improvement stores, but you may get a more affordable deal buying online. For example, you can get a 2-pound bag of oxalic acid with thousands of five-star reviews on Amazon for just $15.85. Along with the acid, you will need protective gear, including goggles and gloves, along with water, a bucket, a sprayer, and a stiff-bristled brush.

After cleaning any dirt and debris from the sidewalk using soap and water, mix 1 cup of oxalic acid into 1 gallon of warm water. Follow the instructions on the product you purchase if they are different. When your mixture is ready, spray or pour it onto the rust stains. Leave the mixture to soak into the concrete for several minutes. For severe stains, scrubbing with a brush after a few minutes can help the acid reach deeper stains. 

Then, rinse thoroughly with cold water to make sure the acid does not stain the concrete. Oxalic acid is unlikely to damage your lawn if it's properly diluted, so you can rinse liberally with water and not worry if the runoff goes into your grass. Also, be sure to rinse before the acid and water mixture dries so that you can rinse away the rust — if you wait for it to dry before rinsing, the stains will likely remain. It may help to save this project for a cool, shady day. When the sidewalk dries, it should be nice and stain-free. Learn how to repair concrete cracks as well, and your sidewalks will be perfect.