A Deep Cleaning Guide for Roughcast Walls

Roughcast walls, like pebble dash or stone/brick chip, have an uneven, textured surface that accumulates dirt and stains over time. Due to their texture, roughcast walls require careful cleaning to remove built-up grime without damaging the surface. The best cleaning method depends on the condition and material of your specific walls. So let us know –

How to clean roughcast wall?


Pressure Washing

Pressure washing is an effective method for sturdy roughcast walls in good condition. Use a variable pressure washer with different pressure settings and spray angles. Start with a lower pressure and higher angle to wet the walls. Then increase the pressure and lower the angle to blast away caked on dirt and stains. For stubborn stains, apply a detergent designed for concrete or masonry and scrub with a stiff brush, then rinse with high pressure.

Be very careful using a pressure washer on roughcast, as the high pressure can dislodge or damage the material if aimed at close range or in one area for too long. Maintain a safe distance and keep the spray moving to avoid excessive focus on one spot. Rinse walls thoroughly when finished to remove any remaining detergent residue. Allow walls to dry completely, which can take 24 hours or longer for roughcast.

Soft Washing

For roughcast in poor condition or if you prefer a gentler and safer approach, soft washing is a good alternative. Mix a pH-neutral concrete cleaner or degreaser detergent with water according to product directions. Use a scrub brush to scrub the detergent onto walls, then let it sit for several minutes so it can dissolve the dirt and stains. Rinse the walls thoroughly with a hose to remove the detergent and loosened grime.

Because soft washing relies on detergent rather than pressure, it’s a safer method for delicate or crumbling roughcasts. However, more scrubbing or repeated cleaning may be required to remove tough stains.

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For stubborn stains or fungal growth remaining after pressure or soft washing, scrubbing by hand may be needed. Apply a concentrated concrete cleaner or bleach solution and scrub stains repeatedly with a stiff brush until removed. Rinse the area thoroughly with water when finished to remove any remaining cleaner. Scrubbing can be tough on the hands, so wear rubber gloves and consider eye/face protection from cleaning splatter.

Allow all cleaning methods to fully dry before evaluating if additional cleaning is needed. For ongoing maintenance, rinse roughcast walls periodically with a hose and scrub any noticeable dirt or stains to prevent buildup. With the proper cleaning approach and regular care, you can keep your roughcast walls looking their best for years to come.

If you don’t want to spend hours scrubbing and deciding what method to use, simply call us today and we will clean the render for you.

[Disclaimer: The cleaning methods and product recommendations in this article are suggestions only. The author is not responsible for any damage, injury, or other adverse effects that may result from the application of the advice or tools in this article. Readers should exercise their own judgement and take necessary safety precautions when following any cleaning recommendations.]