Indoor brick walls and features bring a raw, textured beauty to a space, but their porous nature means they collect dust, grime, and spills over time. Cleaning them requires a different approach than wiping down drywall or painted surfaces to avoid damage or efflorescence. This guide provides a methodical, safe process for restoring your interior brick to its natural best.
Understanding Your Brick and the Initial Prep
Before reaching for any cleaning solution, take a moment to assess the surface. New, sealed brick will handle a gentle cleaning routine, while older, unsealed, or fragile brick may be more sensitive. The goal is to remove dirt without stripping the material or forcing moisture into its core.
Clear the Area and Test for Porosity
Move furniture away from the wall or cover items with drop cloths to protect them from water and cleaning agents. Conduct a simple porosity test by wetting a small, inconspicuous area with water. If the water beads up and wipes away easily, the brick is likely sealed. If it darkens and absorbs quickly, the brick is unsealed, which dictates a gentler cleaning approach to prevent moisture penetration.
The Dry Cleaning Phase: Removing Loose Debris
Never start with water on porous brick, as it can trap dust and minerals inside the pores. Begin with dry methods to dislodge surface dust and loose particles, which is a crucial step for a thorough clean.
Vacuuming and Brushing
- Use the brush attachment on a standard vacuum cleaner to suck up dust and dirt from the brick's surface and the grooves (joints).
- For areas without a vacuum access, use a soft-bristled brush, like a natural-bristle paintbrush or a clean toothbrush, to gently agitate and lift dust from the texture.
Preparing the Cleaning Solution
For most interior brick, a simple and effective solution is the most reliable. Harsh chemicals can discolor or damage the brick, while acidic solutions can etch the surface if not neutralized properly.
The Soap and Water Method
Mix a mild detergent or dish soap with warm water in a bucket. The solution should be gentle; you are looking to create enough suds to lift grime, not a heavily concentrated mix. Agitate the water slightly to create a soapy texture.
The Washing Process: Gentle Agitation is Key
This stage requires patience. The aim is to loosen dirt without aggressively scrubbing the brick face, which can cause scratches or force water into the material.
Application and Rinsing Technique
Dip a clean sponge or a soft cloth into the soapy solution and wring it out well so it is damp, not dripping. Apply the sponge to the brick in a dabbing or light wiping motion, working from the top of the wall downward. This prevents dirty runoff from streaking over cleaned areas. Focus on stained areas but avoid harsh rubbing. Once a section is cleaned, rinse the sponge thoroughly with clean water and wring it out before wiping the soap residue away. If a bucket of water becomes dirty, replace it with fresh water to avoid redepositing grime.
Tackling Difficult Stains and Grout
Not all stains will lift with soap and water. Oil stains, rust, or marker marks require a slightly stronger approach, while the joints (grout) between bricks often need targeted attention.
Specific Stain Treatment and Grout Cleaning
- Grease or Oil: Apply a layer of baking soda or cornstarch to the stain, let it sit for several hours or overnight to absorb the oil, then brush it off and clean the area with soapy water.
- Rust: Use a commercial poultice specifically designed for masonry rust stains, following the product instructions carefully. Avoid using oxalic acid or harsh acids on natural stone brick, as they can cause permanent damage.
- Grout Lines: For dirty grout, use a soft-stiff toothbrush dipped in the soapy solution and scrub the lines. For tough grout stains, create a paste of baking soda and water, apply it to the lines, let it sit for a few minutes, then scrub and rinse.
Drying and Sealing: The Final Protective Steps
How the brick dries after cleaning is just as important as the cleaning process itself. Allow the wall to air dry completely by keeping the area well-ventilated with open windows or fans. Avoid using heat guns or high-heat blowers, which can cause the brick to crack.
Consider Sealing for Long-Term Protection
Once the wall is bone dry, consider applying a breathable masonry sealer. This step is highly recommended for interior brick, as it helps the wall resist future stains, spills, and moisture buildup. Choose a sealer that is satin or matte finish to preserve the natural look of the brick, and ensure it is suitable for interior use. Test the sealer in an inconspicuous area first to confirm the desired sheen and compatibility.
