COMMON RENDER STAINING ISSUES
When it comes to cleaning render, there are a variety of factors to consider in what causes common render staining. Not all stains are the same, and different types of render will respond to different treatments. Understanding which types of render are most likely to stain and how to properly clean them is crucial for maintaining the aesthetic and longevity of a building.
Types of Render Most Likely to Stain
Render, especially external render, is constantly exposed to the elements. It’s a tough material, but it’s still prone to staining. The most common types of render that tend to get dirty or stained include traditional lime-based renders, cement renders, and acrylic renders.
Lime-based renders, while breathable and eco-friendly, are often more susceptible to biological stains such as algae, moss, or lichen. This is because the surface is more porous and retains moisture, providing an ideal environment for these organisms to thrive. These stains are typically green or black in appearance and are more likely to appear in damp, shaded areas or on north-facing walls where sunlight is limited.
Cement renders are a bit more durable and less prone to biological staining, but they can still be affected by environmental factors like pollution or water damage. These types of stains tend to be discolorations or black marks. Acrylic renders, although often more resistant to staining, can still be discoloured by surface dirt, rainwater, and debris.
Metal Stains on Render
One of the most problematic types of stains on render is rust stains from metal components. These stains often appear in areas where metal is in contact with the render, such as around drainpipes, metal flashings, or any other metal fixtures on the building. Rust stains typically manifest as reddish-brown marks that can spread across the surface, creating an unsightly appearance.
Areas that are prone to metal rust stains include the base of downpipes, where rainwater may cause the metal to corrode and transfer rust to the render. Flashing areas, particularly where metal meets render around windows or roofs, can also experience rust stains due to water runoff. If left untreated, these stains can become embedded into the render, making them harder to clean.
Different Treatments for Different Stains
When considering what is render cleaning, it is a whole sub category of the exterior cleaning industry, and specialist approaches are needed. Not all stains on render are the same, and the treatment methods vary depending on the type of stain. For biological stains, such as those caused by algae, moss, or lichen, the best solution is often a cleaner containing sodium hypochlorite (commonly known as bleach). This chemical solution is effective at killing off the growth of organisms and removing the stains they leave behind. It’s important to use the right concentration of sodium hypochlorite to avoid damaging the render.
For metal stains, particularly rust, the solution is different. Simply using bleach will not effectively remove rust stains. Instead, specialised products are available. PureSeal UK, for example, offers a product called Smelly Gel. This gel is specifically formulated to treat rust and metal stains on render. The product works by breaking down the rust particles, making them easier to remove from the surface of the render without damaging it. Smelly Gel is applied directly to the stained area, left to work for a period of time, and then rinsed off. The result is a much cleaner surface, free from rust stains.
In conclusion, when providing a render cleaning service; we appreciate not all render stains are created equal, and there are different ways to clean render. Different stains require different cleaning methods. Biological stains, like those caused by algae or moss, can typically be treated with sodium hypochlorite. For metal rust stains, a product like PureSeal UK’s Smelly Gel offers a targeted and effective solution. By understanding the different types of render and stains, and using the right products, you can ensure your building maintains its appearance for years to come. Always remember, different stains need different treatments, and choosing the right product is key to achieving the best results.
