How to Clean Brick: Interior and Exterior

Brick adds a timeless, rustic charm to any home. However, that textured surface is a magnet for dust, soot, and moss. Whether you are dealing with a dingy fireplace or a grimy home exterior, proper cleaning is essential to preserve the masonry.

We researched the safest, most effective methods to restore your brickwork without causing damage.

Here is your guide on how to clean brick inside and outside your home.

How Often to Clean Brick

Brick is relatively low-maintenance, but it still needs attention to look its best.

• Exterior Brick: Wash your home’s facade once a year to remove dirt and prevent moss growth.
• Fireplaces: Clean the brick surround after every few uses or at the end of the burning season to prevent permanent soot staining.
• Interior Walls: Dust exposed brick monthly. Perform a wet clean once or twice a year, or whenever you spot stains.

Best Cleaners for Brick

You should avoid harsh industrial chemicals when possible, as they can degrade old mortar. Natural cleaners are often enough to do the job. Here are the best options for different messes:

• Vinegar: Mix equal parts distilled white vinegar and water. This is excellent for removing efflorescence (white salt deposits) and general cleaning on newer brick.
• Dish Soap and Salt: Create a gritty paste using equal parts dish soap and table salt. This works well for scrubbing soot stains.
• Cream of Tartar: Mix two tablespoons of cream of tartar with a small amount of water to form a paste. Apply this directly to small, stubborn stains.
• Boric Acid: Dissolve one tablespoon of boric acid in a gallon of warm water. This is a good antifungal option for outdoor areas.
• Bleach: Use this for mold and mildew removal on exterior brick. Mix one cup of bleach per gallon of water.
• Trisodium Phosphate (TSP): This is a heavy-duty cleaner for tough grease or smoke stains. Mix ⅛ cup of TSP per gallon of hot water.
• Pressure Washer Cleaners: For large exterior jobs, use a specialized masonry detergent in your pressure washer to break down road film and grime.

How to Clean Interior Brick

Interior brick, like fireplaces or accent walls, usually suffers from soot and dust accumulation. This method is gentle enough for indoor use.

• Time: 20, 30 minutes.
• Difficulty: Easy.

Supplies Needed

• Vacuum with brush attachment.
• Spray bottle filled with water.
• Cleaning solution (Vinegar/water or soap paste).
• Nylon-bristled scrub brush.
• Drop cloths or old towels.
• Bucket of warm water.

1. Protect and Prep

Lay down drop cloths to protect your flooring from runoff. Use your vacuum’s soft brush attachment to remove loose dust, cobwebs, and soot from the brick face and mortar joints.

2. Mix Your Solution

Prepare your chosen cleaner. For general cleaning, a 50/50 mix of vinegar and water in a spray bottle is easiest. For heavy soot, mix dish soap and salt into a thick paste.

3. Wet the Brick

Spray the brick with plain water first. This is a critical step; dry brick is very porous and will absorb the cleaning chemical instantly. Wetting it first keeps the cleaner on the surface where it can work on the dirt.

4. Scrub the Surface

Apply your cleaning solution. Work in small sections, starting from the top and moving down. Use your nylon brush to scrub in a circular motion.

• Note: Avoid wire brushes, as they can scratch the brick face and leave behind metal bristles that will eventually rust.

5. Rinse and Dry

Dip a clean sponge into a bucket of warm water and rinse the brick thoroughly. You may need to change the water frequently. Once the soap residue is gone, blot the area with a dry towel and let it air dry.

How to Clean Exterior Brick

Cleaning a whole house requires a bit more power. While pressure washers are helpful, you must use them carefully to avoid destroying the mortar.

• Time: 1, 2 hours.
• Difficulty: Intermediate.

Supplies Needed

• Garden hose or pressure washer (low PSI).
• Masonry detergent.
• Stiff broom or brush.
• Tarp and plastic sheeting.
• Protective gear.

1. Prepare the Area

Cover nearby landscaping with tarps. If you are using bleach or chemicals, soak the soil and plants with plain water first; this prevents them from absorbing the runoff. Cover electrical outlets and windows with plastic sheeting.

2. Apply Detergent

If using a pressure washer, fill the tank with a brick-safe detergent like Sun Joe All-Purpose Cleaner. Apply the soap from the bottom up using a low-pressure nozzle. Let it sit for 5 to 10 minutes to break down the dirt, but do not let it dry completely.

3. Scrub (If Needed)

For heavily soiled areas, use a stiff broom or brush to agitate the dirt while the detergent is soaking.

4. Rinse Top to Bottom

Switch to a rinse nozzle or use your garden hose. Rinse from the top down so the dirty water runs off clean sections. Keep the pressure low (around 500 to 1000 PSI) and keep the nozzle at least 12 inches away from the surface.

How to Remove Mold and Mildew

Shaded areas of brick often develop green moss or black mold. Bleach is the most effective remedy for these organic stains.

• Time: 15 minutes per section.
• Difficulty: Easy.

Supplies Needed

• Bleach.
• Bucket and sponge.
• Garden hose.
• Protective gloves and eyewear.

1. Safety Check

Ensure the area is clear of pets and children. Wear old clothes and protective gear, as bleach can damage skin and fabrics.

2. Pre-Wet the Wall

Spray the moldy area with water. As with interior cleaning, this prevents the bleach from soaking too deeply into the porous masonry.

3. Apply Bleach Solution

Mix one cup of bleach with one gallon of water. Apply it to the wall with a sponge or a pump sprayer. Let it sit for roughly 5 minutes. The bleach will kill the spores and lift the stains.

4. Scrub and Rinse

Scrub the area with a stiff brush, then rinse thoroughly with a garden hose. Ensure all bleach residue is washed away to prevent discoloration.

Essential Brick Cleaning Tips

Follow these guidelines to ensure you get the best results without damaging your home:

• Spot test first: Always test your cleaning solution on a small, inconspicuous area before applying it to the entire wall. This ensures the chemical won’t bleach or stain the brick.
• Pre-soak is mandatory: Never apply cleaner to dry brick. The water barrier keeps the dirt on the surface where it is easier to remove.
• Check the weather: Avoid cleaning exterior brick on extremely hot, sunny days. The cleaner will dry too fast and leave streaks. Overcast days are best.
• Gentle pressure: If you use a pressure washer, start with the lowest setting. You can always increase pressure slightly, but you cannot undo damage to mortar joints.
• Use the right brush: Soft nylon or natural bristles are best. Commercial masonry sponges are also excellent for trapping soot without abrasion.

Restoring the Look of Old Brick

Cleaning makes a huge difference, but sometimes brick needs a little more help to look modern. Here are a few ways to refresh tired masonry:

• Repointing: If the mortar is crumbling or cracked, repointing (adding fresh mortar) can stabilize the wall and make it look brand new.
• Painting or Whitewashing: For a dramatic change, consider painting the brick or applying a whitewash (limewash). This allows the texture to show through while brightening the color.
• German Smear: This technique involves smearing wet mortar over the brick face, creating a rustic, old-world cottage look.
• Landscaping: Sometimes the brick looks fine, but the surroundings are dull. Trimming overgrown bushes or planting colorful flora against the brick can improve curb appeal instantly.

FAQs

Why Is My Red Brick Turning White?

This is called efflorescence. It is a crystalline deposit of salts that forms when water is present in or on the brick. As the water evaporates, it leaves a white, powdery residue. It can usually be removed by dry brushing or scrubbing with a vinegar solution.

Does Brick Need To Be Sealed?

Yes, sealing is highly recommended, especially for exterior brick. Because brick is porous, it absorbs water which can freeze and crack the material in winter. A penetrating siloxane sealer repels water while allowing the brick to breathe.

What Does Bleach Do to Brick?

Bleach is an effective disinfectant that kills mold, mildew, and moss. However, it is harsh. If used in high concentrations or left on too long, it can discolor the brick or degrade the mortar. Always dilute it (1 part bleach to 10 parts water is usually safe) and rinse thoroughly.

Bleach Tip

Never mix bleach with ammonia or other cleaners, as this creates toxic fumes. Stick to diluting it with water only.

Does OxiClean Clean Brick?

Yes, OxiClean™ Versatile Stain Remover is a safer alternative to bleach for cleaning organic stains. Mix the powder with warm water according to package directions, apply it to the wet brick, scrub, and rinse. It is oxygen-based and less likely to damage plants.

Will Hydrogen Peroxide Clean Bricks?

Yes, hydrogen peroxide is a good alternative for indoor cleaning or small stains. It works similarly to bleach but is less harsh. You can use it to tackle soot or mildew stains, but always test a small spot first to ensure it does not bleach the brick color.

How Much Does It Cost to Pressure Wash a Brick House?

Professional pressure washing typically costs between $0.40 and $0.50 per square foot. For an average-sized home, you can expect to pay between $200 and $400. This is generally more affordable than cleaning other siding types because brick withstands pressure well, allowing for faster cleaning.

Can I Use Vinegar on Old Brick?

You should be careful using vinegar on very old or antique brick. The acid in vinegar can eat away at the lime found in older mortar mixtures. If your home was built before the 1930s, test a very dilute solution in a hidden area or stick to a neutral pH soap instead.

Beautiful Brick

Restoring your brick to its former glory doesn’t require expensive contractors. With a little elbow grease, vinegar, or a pressure washer, you can wipe away years of soot and grime.

Remember the golden rule: always wet your brick before applying cleaners. This simple step prevents damage and ensures a deep, even clean. Whether you are scrubbing a fireplace or washing the whole house, these tips will keep your masonry looking solid for decades to come.