Rawlins Paints Blog Industrial Paint Tips, Guidelines & DIY Articles
Cleaning masonry and exterior brickwork improves both the appearance of a property and the longevity of the material. Whether you’re tackling a personal DIY project or handling a professional job, using the correct techniques and products can help avoid damaging the surface. This guide covers the essentials for cleaning various types of masonry, addressing common challenges, and maintaining the condition of your brickwork.
Understanding Masonry Cleaning Basics |
Masonry cleaning involves removing contaminants such as dirt, algae, efflorescence, and paint residues while preserving the integrity of the surface. This is vitality important for when you want to paint exterior masonry, ensuring that the surface is suitably prepared. The cleaning approach you choose will depend on the substrate type and its condition.
Porous masonry surfaces, such as brick and concrete, can absorb more water and chemicals, so gentle methods may be necessary. Before starting, assess the surface for any cracks or loose mortar that could worsen with moisture exposure. Certain stains, such as algae or limescale, may need specialised cleaners. Always test a small, inconspicuous area to confirm that the cleaner is safe and effective for the substrate.
Types of Masonry Substrates and Their Cleaning Requirements |
Brickwork
Brickwork is a popular choice for exteriors due to its durability, but it often accumulates grime, algae, and mortar residue. Efflorescence, a white salt deposit, is another common issue that forms when moisture brings salts to the surface. To clean tough deposits effectively, SmartSeal Brick Acid Cleaner is an excellent option for dissolving mortar stains and efflorescence. However, it should be avoided on acid-sensitive surfaces such as limestone.
Concrete Masonry
Concrete masonry is sturdy but prone to surface degradation if exposed to harsh chemicals. For general cleaning and preparation, 108 Surfa Etch Solution is recommended to neutralise alkaline salts and prepare the surface for further treatments or coatings. This etching solution also works well for removing residues from metal surfaces.
Natural Stone
Natural stone, such as limestone, granite, and sandstone, requires careful handling. Acidic cleaners can cause permanent damage to calcium-rich stones. For these materials, a pH-neutral option like Zinsser Universal Degreaser & Cleaner is ideal for lifting dirt and organic stains without causing corrosion.
Preparing for Masonry Cleaning |
Preparation is key to a successful masonry cleaning project. Start by protecting nearby areas with plastic sheeting to shield windows, metal fixtures, and plants from splashes. Inspect the surface for any cracks or weak spots and repair them beforehand to prevent water ingress. Personal protective equipment (PPE) such as gloves, goggles, and suitable clothing is essential to avoid chemical exposure.
Cleaning Exterior Masonry: Step-by-Step Guide |
Removing General Dirt and Grease
For effective removal of dirt and grease, apply Zinsser Universal Degreaser & Cleaner directly to the surface. Scrub the area with a stiff-bristled brush to loosen contaminants. Rinse thoroughly with clean water to ensure a residue-free finish.
Cleaning Cement Residues and Efflorescence
To remove cement residues or efflorescence, use SmartSeal Brick Acid Cleaner. Apply it with a brush, allow it to sit for a few minutes, then scrub the area and rinse thoroughly. Avoid using this product on polished stone surfaces, as it may cause damage.
Preparing Concrete and Metal Surfaces
For concrete and metal surfaces requiring preparation before painting, apply Surfa-Etch 108 generously. Scrub the solution into the surface and let it work for 10 to 15 minutes. Rinse thoroughly and allow the surface to dry completely before applying any coatings.
Treating Moss, Mould, and Algae
Eliminate moss, mould, and algae with a suitable biocide. Apply the solution evenly across the surface and follow the manufacturer’s guidelines for dwell time and rinsing to prevent regrowth effectively.
Each of these steps ensures optimal surface preparation for long-lasting results.
Addressing Common Cleaning Challenges |
Efflorescence
Efflorescence is a frequent issue for brick and concrete. It occurs when moisture carries soluble salts to the surface, leaving white streaks or patches. To combat this, apply SmartSeal Brick Acid Cleaner to affected areas and rinse thoroughly.
Paint Stains
Paint stains on masonry can be stubborn. A wire brush can help loosen dried paint before applying Zinsser Universal Degreaser & Cleaner to soften any remaining residues.
Rust Stains
Rust stains from metal fixtures often appear as reddish streaks. Surfa-Etch 108 is effective for removing these marks, as it neutralises corrosion products such as white rust from galvanised metal.
Product Recommendations for Masonry and Brick |
Zinsser Universal Degreaser & Cleaner: This versatile, water-based solution from Zinsser is ideal for general grime, grease, and adhesive residue removal.
SmartSeal Brick Acid Cleaner: Ideal for dissolving cement and mortar residues, as well as efflorescence, though it should be avoided on acid-sensitive surfaces.
Surfa-Etch 108: A powerful etching solution for concrete, galvanised steel, and aluminium, ensuring better paint adhesion.
Wethertex AP77: A highly durable, weatherproof paint that offers a breathable and self-cleaning finish for up to 20 years. Ideal for application on cleaned surfaces.
Post-Cleaning Maintenance and Treatment |
Once the masonry is clean, regular maintenance can prolong its pristine appearance. Inspect the surface periodically for new cracks or signs of water ingress. Painting masonry with AP77, a high-quality product from Wethertex, provides an extra layer of protection and enhances weather resistance. See our blog post “The Benefits of Masonry Paint” for more information.
To further reduce moisture penetration, consider applying a breathable water-repellent masonry sealer. Applying a protective coating after cleaning not only safeguards against future staining but also helps prevent algae and mould growth. Be sure to follow the drying time recommendations to achieve the best finish.
Whilst painting masonry, you may wish to update the colour of your uPVC windows and doors, gutters, downpipes, etc. Clean and sound uPVC and composite can be painted in 5,000+ colours, and is much cheaper and less hassle than replacing your existing windows and doors with, say, the latest Anthracite Grey style, when you can simply paint it!
Conclusion |
By following these steps, you can effectively clean and maintain exterior masonry and brickwork, ensuring a professional and long-lasting result. Proper product selection and technique make all the difference in achieving a clean, protected surface that stands the test of time. Dispose of any cleaning residues responsibly and in accordance with local regulations to minimise environmental impact.