Rust stains on cement are a common problem for homeowners, especially well water users, because well water generally contains high levels of iron. The appearance of such stains is difficult to prevent and can interfere with the view if not cleaned. Although rust stains can't be completely removed, you can remove most of them.
Step
Method 1 of 3: Cleaning Minor Stains
Step 1. Rinse and wash the cement with soap and water before starting
Dirt and dust will hinder stain removal, making the process less effective. After the cement surface is cleaned, allow it to dry first.
Step 2. Pour or spray lemon juice on the rusty surface
Most rust removers use acid to clean and remove stains. The high concentration of citric acid in real lemon water is a cleanser worth trying. Pour lemon juice on the rust and let it sit for 5 to 6 minutes before scrubbing it off with a wire brush.
Step 3. For stubborn stains, pour or spray white vinegar instead of lemon juice on the rusty surface
Let it sit for a few minutes before scrubbing it with a wire brush. Rinse off the rust with ice water and repeat this step for tough stains.
Step 4. Scrub the cement surface with a brush
Let the lemon water or vinegar sit for 5-10 minutes. Scrub the surface with a stiff nylon brush if the cement surface is smooth or painted. Scrub in small circular motions to remove as much of the rust stain as possible.
Do not use a metal brush as it can scratch the fine cement plaster on the top surface
Step 5. When finished, rinse the cement with cold water
After rinsing, let the cement dry. You may need to re-clean any rust stains that remain after the cement dries, as repetition is the best way to clean them.
Step 6. Use a sponge and diluted vinegar to scrub smooth or painted surfaces
If using a wire brush risks damaging the surface, just use a sponge and vinegar diluted with warm water. But make sure you test the material first into a small corner or hidden part of the cement, as a lot of acid can peel off and damage the paint. Dilute 1 cup of vinegar with half a cup of water, then rub gently in a circular motion. This step may need to be repeated up to 3-4 times because the more often it is repeated, the cleaner the result will be.
Method 2 of 3: Cleaning Stubborn Rust Stains
Step 1. Use a commercially available cleaner if vinegar and lemon water don't work
For heavy, stubborn stains, you should use a strong cleaner. Rinse the cement and let it dry before applying the cleaning chemical. Make sure you take security measures such as:
- Work in a well-ventilated area.
- Use gloves and protective eyewear.
- Wear long sleeves and long pants to protect your skin.
Step 2. Use a cleanser that contains oxalic acid, such as Singerman or F9 BARC
This spray is usually used to clean sinks without damaging them, and can remove rust stains quickly.
- There is a form of liquid or powder.
- Spray or sprinkle the cleaner onto the rusty surface. If the cleanser is a powder, wet it with water.
- Let the cleaner sit for a few minutes before moving on to the next step.
Step 3. Use trisodium phosphate to remove stubborn rust from cement
Mix cup (118.29 ml) of trisodium phosphate with 1.89 liters of hot water. Trisodium phosphate can be purchased at a hardware store and the solution mixture can be made at home.
- Pour the solution onto the rusty surface.
- Leave it for 15 to 20 minutes.
Step 4. Scrub the surface with a stiff nylon brush and then rinse after the cleaner has worked
As before, don't use a wire brush as it can damage the smooth finish of the cement stucco. We recommend using a stiff nylon brush and brushing in small circular motions to remove any stains. When finished, rinse all cleaning agents thoroughly. Cleaning agents left in cement for too long can cause discoloration.
Step 5. Consider wisely whether you need to use hydrochloric acid to remove the stain
In some tests, hydrochloric acid was the most effective ingredient for removing stains. However, if this acid is allowed to sit too long, the cement will turn blue. So you have to work fast. Dilute every 2 cups of acid with 1 cup of water to give you more time to clean the stain while reducing the risk of the cement surface turning blue.; always mix acid to water to avoid a violent reaction.
- Let the acid sit on the stain for 5-10 minutes.
- Quickly scrub away the rust stains.
- Rinse the surface with water until it is completely clean.
- Repeat if necessary.
Step 6. Use a high-pressure water spray for hard-to-reach or stubborn stains
If you're having trouble removing the rust stain, or if it's impossible to scrub harder, let the acid sit on the stain for 10 minutes and prepare a high-pressure water spray. This spray will remove any residual acid and apply concentrated pressure to the stain so that rust can be removed easily from the cement surface.
Method 3 of 3: Preventing Rust Stains
Step 1. Seal the cement with a protective film to prevent rust stains
The cement seal is applied like applying paint to wood, and the seal absorbs into the pores of the cement and protects it from stains. You can get cement seals at building materials stores. For best results, reapply seal every 2-3 years:
- To apply the seal, choose dry days when rain is not expected to fall in the near future.
- Wash the cement and remove any stains.
- Start at the corner, then apply the seal to the entire surface of the cement.
- Allow the seal for 48 hours to dry before you place the furniture on it.
Step 2. Do not place metal legged furniture directly on cement
If you have to, move furniture when it rains. One of the main causes of rust stains is wet outdoor metal furniture. However, the appearance of rust can be prevented with some precautions.
- You can put a mat, outdoor rug, or mat to protect the cement.
- The cement in the room cannot be separated from rust stains if the room is damp or wet. So, pay attention to the parts of the cement that are in direct contact with the metal.
Step 3. Make sure you use stainless steel rods as scaffolding when installing the concrete
Some rust stains come out of the cement due to water seeping into the metal scaffolding and causing rust stains to appear in the concrete. The best way to prevent this is to be proactive, making sure you buy and choose rust-resistant metal rods for building foundations.
Step 4. Check for leaks in your home
Moisture can cause rust. So if you find rust stains on the cement surface in the house, check the house for possible leaks. The sooner you seal the leak, the better, because moisture can do more damage than the stain it produces.
Tips
- If the stain was caused by metal scaffolding protruding from the cement, protect the cement with a cement seal after you've cleaned the rusty surface, to prevent rust from reappearing in the future. Cement seals can be purchased at building materials stores. Follow the product instructions on the packaging.
- To reduce the risk of rust stains appearing, do not spray water on the cement surface when you water the lawn.
- For best results, use a high-pressure water spray to rinse off rust stains and residual cleaning fluid.
