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Rust is the process by which a compound that contains iron corrodes after it has been exposed to water and oxygen. Rust is an unattractive sight on any surface or object, and rendered surfaces are no exception. Rust on rendered walls can be caused by a multitude of different reasons, including overflowing pipes, steel fixtures, flute pipes and satellite dishes.

Continue reading to find out more about rust on rendered surfaces.

What is Rust?

Rust (also known as oxidation) is the result of a compound corroding when it contains iron and is exposed to water and oxygen. The rusting process transforms iron into iron oxide, which makes it a brittle material that is recognisable by its red and brownish colour and is easy to break. Rust stains can take months to first appear.

What Causes Rust on Rendered Surfaces?

Rust is formed on rendered surfaces by:

  • Metal ventilation grates
  • Satellite dishes
  • Overflow pipes
  • Steel fixtures
  • Flue pipes
  • Metal frames and borders
  • Gutters
  • Downspouts
  • Hanging basket brackets
  • Moisture
  • Pollution
  • Damp conditions

Rust can form on rendered surfaces when metal features or fixtures on your structure start to rust, which causes rust flakes to travel down to your rendered surfaces, especially during rainfall. Any metal fixtures underneath the render may also corrode and rust due to damp and humid conditions. These rust stains may eventually show through the render, causing an unattractive appearance.

How Does Rust Affect Render?

Thankfully, rust does not cause any significant structural damage. Its main downsides include its appearance. Rust can make your property look old and uncared for, which may bring down its curbside value and give it an overall poor image. This impression is especially problematic if you’re planning on selling your home or if it’s a commercial property and you’re looking to attract/retain business.

How to Remove Rust Stains from Render

If you do a Google search, you’ll undoubtedly find many solutions for removing rust from rendered surfaces. Some of these solutions are more effective than others.

What doesn’t work so well:

  • Paint: Painting over a rust stain is easy and relatively effective—at first. However, it is also like sticking a band-aid over a problem; over time, the rust stains will begin to show again.
  • Using a chemical gel: This can cause its own stains over time, so it is best to avoid it.

Effective ways to remove rust stains, according to Rockcote:

  • Removing object: Before getting rid of the rust stains, it might be worthwhile removing the object that caused the rust stains in the first place. Of course, that’s only if you can remove that object without causing damage to the structure.
  • Brush: Use a soft brush like a toothbrush and a mild acid solution to reduce the rust stain as much as possible. Diluting the solution with warm water works best.
  • Clean water: Once the solution has been applied to the wall, rinse it with water to prevent the paint from becoming stained or bleached.
  • Refilling: Once the surface is dry, touch up the rust stain with a polymer render.
  • Paint: Once the render has dried, apply a touch-up of paint. If the wall colour is faded, you may as well go ahead and paint the whole surface once again.

Other effective ways to remove rust stains include:

  • Chemical stain remover or oxygen bleach: Clean the affected area with a chemical stain remover or oxygen bleach. If the rust stains are stubborn to remove, you may need to apply the solution more than once and scrub thoroughly.
  • Repaint and reseal: Repaint and reseal any metal fixtures and redirect water runoff to avoid rust stains from forming again.

If you notice rust stains forming on your rendered surfaces, don’t fear! Give us a call, and we’ll tell you how to safely and effectively remove the stains.

Sydney Cement Rendering takes pride in being Sydney’s trusted rendering experts and providing our customers with the highest quality rendering services. Contact us at 0402 704 984 or visit our website: https://sydneycementrendering.com/ to find out more about what we offer!