Content

• Steps
• Advice

Stains on cement due to rust are a common problem many homeowners encounter, especially in homes that use well water, as well water is often high in iron. These stains are difficult to prevent and will look very prickly if not cleaned properly. The rust stains are difficult to clean completely, but you can significantly fade them.

Steps

Method 1 of 3: Remove small rust

1. 

   Wash concrete with soap and water before starting to rust. Dust gets in between the detergent and the stain, making your job less efficient. Once you've cleaned the surface of the concrete, you should wait to dry before proceeding.

2. 

   
   
   Pour or spray lemon juice on the rust. Almost all rust cleaners use acid to remove and scrub stains. The high concentration of citric acid in pure lemon juice makes it a good candidate for cleansing. Pour lemon juice over the stain and wait 10 minutes before scrubbing with the iron brush.

3. 

   
   
   Pour or spray white vinegar over the rust instead of lemon juice to remove stubborn stains. Let the vinegar soak for a few minutes before scrubbing with the iron brush. Rinse off the rust with cold water and repeat this process again for stains that are difficult to clean.

4. 

   Scrub the concrete surface with a brush. Let the lemon juice or white vinegar soak for about 5-10 minutes. Use a hard nylon brush to scrub if the surface is smooth and painted. Rub in small circles to remove rust as much as possible.
   • Do not use a metal brush because brushes of this type can remove the mortar layer on the concrete surface and reveal the adhesive material underneath.

5. 

   
   
   Rinse the concrete with cool water after the scrubbing is complete. After rinsing, wait for the concrete to dry. You may want to treat the stain again, as repeated washing is often the best way to completely remove the rust.

6. 

   Use a sponge and diluted vinegar to scrub easily damaged or painted surfaces. If you do not want to use an iron brush for fear of damaging the surface of the concrete, use a sponge and warm water. However, you need to test the cleaner on a small corner of the concrete first - many acids can cause the polish to peel off or damage the paint. Dilute 1 cup of vinegar with ½ cup of water and begin gently rubbing in a circular motion. You may need to wash it 3-4 times, but it will work out over time. advertisement

Method 2 of 3: Treating big rust

1. 

   Switch to commercial detergent if vinegar and lemon are not working. For large stains that are difficult to remove, you will need to resort to strong detergents. Wash the concrete and allow it to dry before using any of the following chemicals, and remember to observe the following safety precautions:
   • Work in a well-ventilated place.
   • Use gloves and goggles.
   • Wear pants and a long-sleeved shirt to protect your skin.

2. 

   Use an oxalic acid cleaner, such as Singerman's or F9 BARC. These products are often used to clean sinks without scratching them, and they act to remove rust quickly.
   • These cleaners are usually in liquid or powder form.
   • Spray or sprinkle cleaning product on the rusted surface. If using detergent, wet it with a little water.
   • Let the detergent soak for a few minutes before proceeding again.

3. 

   Use sodium phosphate (TSP) to clean stubborn rust marks. Mix ½ cup (120 ml) TSP with 2 liters of hot water. You can buy TSPs at home repair shops and bring in water.
   • Wear gloves before using TSP.
   • Pour the mixture over the rusted surface.
   • Let the mixture soak for about 15-20 minutes.

4. 

   Scrub with a hard nylon brush and rinse after detergent has absorbed. As above, you should not use metal brushes, as this can lead to loss of coating on the cement surface. Use a hard nylon brush and rub with a circular motion to remove the stain. Rinse off the detergent when the scrub is finished, taking care to wash it thoroughly. Detergent can discolor aerated concrete that has remained on the surface for a long time.

5. 

   Consider using hydrochloric acid to remove any stains. Several tests show that hydrochloric acid is the most effective material for removing rust marks. However, this type of acid can stain concrete green if it stays in place for too long, so you need to act quickly. Dilute 2 cups of acid with 1 cup of water to allow more time and avoid discoloration of the concrete; Always add acid to the water to avoid strong reaction.
   • Let the acid soak in the stain for 5-10 minutes.
   • Scrub away rust with quick action.
   • Wash the concrete surface thoroughly with water.
   • Repeat if necessary.

6. 

   Use a high-pressure cleaner to clean stains that are hard to reach or difficult to clean. If the stain is hard to reach or can't be brushed harder, you can let the acid soak in for 10 minutes and have a high-pressure cleaner. The powerful jets of water not only help you remove the acid, but also use concentrated force to easily remove the stain. advertisement

Method 3 of 3: Prevent rusting stains

1. 

   Paint on the concrete surface to provide the best protection against rust. Concrete coatings are used as lacquer finishes and will soak into small holes in the concrete, helping to protect the concrete from staining. You can buy this paint at home repair shops. For best results, you need to repaint every 2-3 years:
   • Choose a weekend with less chance of rain to work on.
   • Wash the concrete and clean any stains.
   • Starting from the corner, roll the coating over the concrete surface.
   • Wait 48 hours for the paint to dry before placing the furniture on a concrete surface.

2. 

   Avoid placing metal legs on the concrete. If you can't avoid this, try to move the item away when it rains. Wet outdoor metal furniture is the number one cause of rust, but this can be easily avoided if you are careful.
   • Buy a felt pad or outdoor carpet to protect your concrete.
   • Try painting on metal furniture to prevent rust. You can also coat rusty furniture to prevent rust from spreading to the concrete.
   • Even interior concrete can rust if the room is humid, so be careful of any contact between metal and concrete.

3. 

   Be sure to use stainless steel when pouring concrete. Some stains leak out from the concrete, as water seeps into the reinforcing bars and causes rust inside the concrete. The best way to prevent this is to be proactive - make sure to use stainless steel when making your home.

4. 

   Check for leaks in the home. Humidity causes rust. So if you see stains on interior concrete, you should inspect your home for leaks. You fix it as soon as possible, as the moisture can do more damage than a few rustes that you can easily clean. advertisement

Advice

• If a protruding reinforcement bar on the cement surface causes rust, repaint the surface with a concrete coating after cleaning to prevent future rusting. This product can be found in building materials stores. Remember to follow the directions on the package.
• To minimize rust stains, you should avoid spraying water on the concrete surface while watering your lawn.
• For best results, use a high-pressure cleaner to wash concrete.