Stains On Render
Over time, it is normal for your render to become covered in black, green or red stains due to algae, fungus, dirt build-up, and exposure to the elements. Luckily, these stains are fairly easy to remove. However, some stains may require more effort to completely remove from the surface.
Continue reading to find out more about stains on rendered surfaces.
What Causes Stains on Rendered Surfaces?
There are several reasons why your rendered walls may be covered in stains. The leading causes include:
- The growth of microorganisms, including algae, moss or lichens
- Dirt and grime build-up
- Efflorescence (water stains)
- Poor application of the render
- Broken gutters
- Areas with lots of moisture and little sunlight
- Bird droppings
Green Algae
Green algae is the most common type of algae, and although it can spread quite quickly, it is the least serious type of algae. It is caused by damp and humid weather conditions and results in green or brownish-slimy patches.
How to Remove Green Alage Stains
The best way to clean green algae include:
- Low-pressure washer (best done by professionals).
- Soft washing (a low-pressure washer and a cleaning detergent).
- Fungicides and biocides.
Red Algae
Red algae marks are more challenging to remove than green algae stains, but they are still removed relatively easily with the proper methods.
How to Remove Red Algae Stains
Here are the best ways to remove red algae stains:
- Steam cleaning using hot steam and water. (Best done by professionals).
- Soft washing (low-pressure washer and a cleaning detergent).
Black Algae
Black algae is more serious than both green and red algae. It can spread all over the building structure. If you notice black algae, you need to act quickly to remove it before it spreads.
How to Remove Black Algae Stains
The most effective way to remove black algae stains is by using a:
- If the black stains aren’t too severe, you can try using a simple household cleaner like water and baking soda and scrub the surface with a brush
- Soft wash: Use bleach, algaecide, biocides and water to kill off the algae and prevent regrowth
Moss, Mould and Mildew
Moss, mould, and mildew are fungal growths that thrive in damp and humid conditions. They can develop in green or black spots on surfaces.
How to Remove Fungal Stains
The best way to remove fungal growth stains include:
- A fungicidal wash
- A mould-killing detergent
- A diluted vinegar or bleach solution
- Contact a professional to help remove more stubborn stains
Lichens
Lichen is a complex mix of algae and fungi that appear as a crusty textured growth.
How to Remove Lichens
The best way to remove lichens from rendered surfaces include:
- Pressure cleaning
- Soft washing
Efflorescence (Water Stains)
After lots of rain and moisture, a crusty white mineral deposit can form on rendered surfaces.
How to Remove Efflorescence
The most effective ways to remove efflorescence stains include:
- Use a stiff bristle broom to brush off as much of the mineral build-up as possible
- Warm water
- Chemical cleaners
- Pressure cleaning
Bird Droppings
Bird droppings are not only unsightly, but over time, they can cause damage and decay to the structure due to the acid found in their droppings.
How to Remove Bird Droppings
The best way to remove bird droppings from rendered surfaces include:
- Pressure wash on the ‘fan’ setting
- Warm water, baking soda or detergent and a stiff bristle brush or broom
How to Prevent Stains on Render
The best ways to prevent stains on rendered surfaces include:
- Regular cleaning: Regularly hose down rendered exterior surfaces with a soft pressure washer or a hose and stiff brush or broom.
- Maintenance: Check your rendered surfaces regularly for any signs of cracks or stains.
- Sealants and Coatings: Using a protective sealant or coating can help prevent moisture, grime and debris from penetrating and staining the rendered surfaces.
- Proper drainage: Ensuring that your gutters, drains and downspouts are all working properly can prevent any water damage.
If you notice stains on your rendered surfaces, it is best to contact a professional rendering company before attempting to clean the render yourself. A rendering company will be able to tell you the direct cause of the stains and how to safely and effectively remove them.
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!