How to Clean Brick? | The Right Way, Step by Step

Cleaning brick the wrong way—say, pointing a pressure washer at it or reaching for muriatic acid—can permanently damage the face of the brick and leave you with a worse problem than dirt. The trick to cleaning brick is resisting the urge to go aggressive and instead matching the method to the mess. Here is the process that works, the tools to use, and the mistakes that cost people their brickwork.

What You Need Before You Start Cleaning Brick

Gather the right supplies before you get wet. A stiff-bristle brush with nylon or natural bristles is your main tool; the Brick Industry Association recommends a soft bristle brush over metal or wire options, which can scratch the brick’s face and leave rusting fragments behind.

• Stiff non-metal brush for scrubbing the surface
• Mild dish detergent or a pH-neutral masonry cleaner
• Clean water and a hose with a standard nozzle
• A bucket for mixing your cleaning solution
• Drop cloths to protect landscaping and nearby surfaces

Skip the wire brush, metal scraper, and muriatic acid entirely. The Brick Industry Association specifically warns against muriatic acid, noting that even diluted, it should be avoided unless a manufacturer-approved specialty cleaner is specified. A quick test on a small, hidden area first is non-negotiable—the GSA and brick-industry sources all stress this as the first step.

The Step-by-Step Method for Cleaning Brick

This proven sequence removes dirt and staining while protecting the brick’s surface. Work from the bottom up when rinsing to avoid streaking, and always keep the brick wet while cleaning.

1. Dry-brush the surface. Remove loose dirt, dust, and mortar smears with a stiff non-metal brush before any water touches the brick.
2. Pre-wet the brick thoroughly. Saturating the surface first reduces how much cleaner and dissolved dirt the brick absorbs, which prevents chemical penetration and blotchy results.
3. Apply the gentlest effective cleaner. For light dirt, a mild detergent mixed with water works well. For heavier staining, use an approved masonry cleaner and follow the manufacturer’s dilution and dwell-time directions exactly.
4. Scrub with a stiff non-metal brush. Work the solution into the surface with firm, even strokes, paying extra attention to stained areas.
5. Rinse thoroughly with clean water. Rinse from top to bottom to push dissolved residue off the wall, and keep rinsing until the water runs completely clear.

Never let the cleaner dry on the wall. If it dries, it can leave residue and streaks that are far harder to remove than the original dirt. Rinse as soon as you finish scrubbing each section.

Heavy Stains and Efflorescence: When to Step Up the Method

For stubborn stains like efflorescence or heavy grime, a dedicated masonry cleaner or a specific chemical solution may be necessary—but only after gentler methods have failed. The GSA’s guidance for brick masonry offers two formulas: for light dirt, mix 1/2 cup trisodium phosphate plus 1/2 cup laundry detergent in 1 gallon of water; for rough-textured brick, dissolve 1 lb of oxalic acid crystals in 1 gallon of water. Both require thorough rinsing after application.

If you use an acid-based cleaner, neutralize the surface afterward with a compatible neutralizer or a diluted vinegar solution per GSA guidance, then rinse again. Masonry cleaners are commonly diluted 16 parts water to 1 part concentrate, but the GSA notes that dilution should be adjusted based on sample-panel cleaning tests. Try your mixture on a small, inconspicuous area first.

For efflorescence—that white, chalky powder that appears on new or damp brick—first identify and fix the moisture source, or the staining will return no matter how well you clean. If staining reappears after cleaning, do not keep recleaning with the same agent; contact the brick manufacturer or a qualified masonry professional for guidance.

Power Washing and Common Cleaning Mistakes

Pressure washing gets mentioned often, but it deserves caution. The Brick Industry Association warns that power washing can permanently damage brick if done improperly—high pressure can erode the brick’s face and blast mortar out of the joints. If you do power wash, treat it as a professional task rather than a default DIY step, and never use high-pressure spray to apply cleaning chemicals, as General Shale warns this drives the chemicals deeper into the brick and mortar.

Avoid these common mistakes that damage brick:

• Wire brushes and metal scrapers—these scratch the brick face and can leave rust stains
• Muriatic acid—too aggressive for casual use; avoid unless a manufacturer-approved specialty cleaner is specified
• Letting cleaner dry on the wall—this increases residue problems and can cause permanent staining
• Pressure washing blindly—improper technique permanently damages the brick finish
• Repeatedly recleaning with the same agent—if staining returns, consult the brick manufacturer first

If your brick needs a heavy-duty cleaner, check our roundup of the best brick cleaner products tested for masonry work before you buy. For most routine cleaning, though, the bucket-and-brush method is all you need.