How to Remove Mortar Haze and Stains from Brick Without Damaging the Surface?

Brick walls, fireplaces, and tiles often show a white film or cloudy layer after installation. That haze comes from leftover mortar or grout. Other stains, like powdery white spots or dark smudges, can appear over time. Interior and exterior brick can both show these problems.

Many people want to clean their brick but feel unsure about what tools or cleaners are safe. Harsh scrubbing or strong chemicals can scratch the surface or damage the color. Thin brick, in particular, needs gentle care.

This article will present you clear methods for removing haze and stains using basic tools, gentle techniques, and trusted products.

Methods to Remove Mortar Haze from Brick

Mortar haze is a thin, white film that shows up on brick after installation. It hides the real color and texture. Thin brick, tile, and full brick can all get haze. Do not scrub hard or use harsh chemicals. That can ruin the surface.

Start With a Dry Cloth

A soft dry cloth can remove light haze from brick without damage

Use a dry cheesecloth or soft towel. Rub the brick in circles. This lifts light haze without adding water or smearing. Best for:

• Thin haze on fresh brick

• Indoor walls or backsplash

• Areas without sealant

Tip: Refold the cloth as it loads up with dust. Never use wet cloth for this method.

Use a White Vinegar Mix on Standard Brick

Vinegar works well on clay brick or unglazed tile. Do not use on stone or sealed surfaces.

Steps:

1. Mix 1 part vinegar with 4 parts warm water

2. Apply to the haze with a sponge

3. Wait 5 minutes

4. Scrub with a soft nylon brush

5. Rinse with clean water

6. Dry with a clean towel

Avoid vinegar on:

• Limestone

• Marble

• Travertine

• Any sealed or polished brick

Try a Baking Soda Paste for Sensitive Brick

Baking soda paste is great for sensitive or indoor brick surfaces

For indoor brick or anything that might react to vinegar, use baking soda. Works well on thin brick and decorative tile.

How to use

1. Mix 3 parts baking soda with 1 part water

2. Spread the paste over the haze

3. Let it sit 10 minutes

4. Scrub with a nylon brush

5. Rinse and dry completely

Good for:

• Kitchen backsplashes

• Painted brick

• Thin brick with color coating

Use a Commercial Haze Remover for Stubborn Spots

Grout haze removers come in acidic and non-acidic versions. Always pick one made for brick or tile. Gel formulas work best on vertical surfaces.

Follow the label exactly. Always test a small spot first.

Acidic	Thick haze on clay brick	Stone, sealed tile
Non-acidic	Indoor surfaces	—
Gel-based	Vertical walls	Never leave to dry

Tip: Wear gloves and eye protection. Work in small sections. Rinse well after.

Mortar Dissolver for Heavy Dried-On Haze

Use this only if haze has hardened over time.

Steps:

1. Apply mortar dissolver gel to the haze

2. Wait 10–20 minutes

3. Scrub gently with a nylon brush

4. Rinse fully and wipe dry

Do not let the product dry on the surface. Do not use in direct sun or heat.

How to Deal with Efflorescence and Salt Stains

Efflorescence looks like white powder on the brick surface. It happens when water pulls salt out of the brick or mortar. It shows up often on outdoor walls, chimneys, and floors.

Brush It Off When Dry

Efflorescence appears as white powder and can be removed with dry brushing

Start with a stiff nylon brush. Brush the dry powder away. Do not add water yet. Do not scrub with metal.

Good for:

• Early stage salt buildup

• Outdoor brick

• Garage or basement walls

Tip: Sweep or vacuum the dust. Do not let it blow into air vents or onto nearby furniture.

Rinse With Clean Water

Use a hose outside or a sponge and bucket inside. Rinse away leftover powder. Let the surface dry. Repeat if needed.

Avoid high-pressure washing unless the brick is heavy-duty exterior masonry.

Use Vinegar Water to Dissolve Salt

If powder stays after rinsing, try the vinegar method:

1. Mix vinegar and water 50/50

2. Sponge or spray on the stains

3. Let it sit 5 minutes

4. Scrub with nylon brush

5. Rinse and dry

Do not use vinegar on stone brick. Use only on clay or standard brick.

Use a Product for Efflorescence

Some cleaners are made just for salt stains. Pick one marked efflorescence remover and safe for masonry.

Steps:

• Follow label directions

• Apply and scrub

• Rinse well

• Wipe dry

Good brands include Aqua Mix and similar products used in brick care.

Do Not Use Harsh Acid

Avoid muriatic acid unless you are trained. It can burn the brick, strip color, and damage joints. Most stains come off with lighter methods.

What Works on Grease, Rust, and Soot

Brick surfaces pick up more than just mortar haze. Grease, soot, and rust stains show up on both indoor and outdoor brick. Kitchens, fireplaces, and patios often need extra attention.

Grease and Oil Stains on Brick

Cornstarch naturally absorbs grease from porous brick floors

Grease can sink into porous brick, especially on floors or near cooking areas.

Step-by-step:

1. Cover the stain with cornstarch or talcum powder

2. Let it sit for a few hours

3. Brush or sweep the powder away

4. Scrub the spot with warm water and mild dish soap

5. Rinse and dry with a towel

Repeat if needed. Powder lifts the oil. Soap clears the rest.

Tip: For thick stains, try an oxygen-based cleaner like Stain Solver. Always test on a small area first.

Soot and Smoke on Fireplace Brick

Black soot builds up fast around wood-burning fireplaces. Never use acid here. Go with soap and water.

Best method:

1. Mix 1/4 cup clear dish soap in 4 cups warm water

2. Wet the brick first

3. Scrub with a nylon brush

4. Rinse and wipe with a clean towel

Tip: Wetting first keeps soot from soaking deeper into the brick.

Rust Stains on Brick Surfaces

Rust leaves orange or brown marks. It usually comes from metal near the brick (furniture, pipes, tools).

Steps:

1. Soak the stain with white vinegar

2. Let sit 5 to 10 minutes

3. Scrub with a soft brush

4. Rinse with water and dry

For stubborn stains, use a cleaner with oxalic acid. Follow label directions. Test first.

Tools and Products That Will Not Damage the Surface

Gentle tools protect your brick while cleaning stains and haze.

Brick is tough, but the surface can still wear down or scratch. Using the right tools matters just as much as using the right cleaner.

Brushes: Soft but Effective

Never use metal bristles. They leave scratches and rust marks.

Best options:

• Nylon scrub brush

• Soft or medium household brush

• Old toothbrush for tight corners

Always scrub gently, in circles. Rinse often.

Cloths and Towels

Use soft towels, microfiber cloths, or cheesecloth. Avoid rough rags or scouring pads.

• Dry cloth use: Lifts light haze

• Wet cloth use: Rinses and dries the area after scrubbing

Best Cleaners for Brick

Choose cleaners made for masonry or tile. Always read the label. Do not use bleach on color-coated or sealed brick.

Vinegar mix	Mortar haze, light salt stains
Baking soda paste	Indoor use, delicate surfaces
Oxygen cleaner	Grease, mildew, deep dirt
Efflorescence remover	Salt buildup
Mortar dissolver	Old dried mortar haze

Avoid anything with strong acid unless you are cleaning tough exterior stains and know the risks.

Recommended Products:

• 511 Miracle Porous Plus – Used after cleaning for sealing

• Aqua Mix Sealers Choice – Good water-based sealer

• Aqua Mix Haze Remover – Gel cleaner for mortar haze

• Stain Solver – Powder cleaner for grease and dirt buildup

How to Clean Interior vs Exterior Brick

Interior and exterior brick face different conditions. Interior surfaces deal with dust, grease, and light haze. Exterior walls face rain, sun, salts, and heavy buildup. Cleaning must match the location.

Interior Brick: Gentle First

Soft cloths and gentle methods protect indoor brick surfaces

Use mild methods for indoor surfaces. Thin brick, tile, and sealed brick need a soft touch.

Best methods:

• Dry cheesecloth for haze

• Baking soda paste for residue

• Dish soap and warm water for everyday dirt

• Vinegar mix only on unsealed clay brick

• Avoid strong chemicals indoors

Tools to use:

• Nylon brush

• Soft towel

• Sponge or spray bottle

• Small bowl for pastes

Work in small areas. Always dry the brick after cleaning to stop water spots or new haze.

Exterior Brick: Watch for Salt and Moisture

Dry brushing removes salt stains from exterior brick without damage

Outdoor brick builds up dirt and salt over time. Rain pulls minerals out from mortar. That leaves powder and streaks.

Best methods:

• Dry brushing for loose salt

• Hose rinse to remove buildup

• Vinegar solution for stains

• Efflorescence remover for deep salt deposits

• Mortar dissolver for crusted haze

Clean on a cool, overcast day. Do not apply cleaners under strong sun or on hot brick. That can cause streaks or dried residue.

Extra help: Use a garden sprayer for large walls. Keep water handy for rinsing.

What to Avoid When Cleaning Brick

Using the wrong method can stain, scratch, or fade your brick. Always avoid shortcuts or harsh tools.

1. Do Not Use Metal Brushes

Steel wool or metal bristles can scratch brick and leave rust marks. Use nylon or soft plastic only.

2. Do Not Use Harsh Acids Without Skill

Muriatic acid burns brick, ruins color, and can damage mortar joints. It should only be used by professionals on heavy-duty exterior walls.

3. Do Not Clean in Direct Sunlight

Sunlight dries out the cleaner before it works. It can also leave marks or streaks on the surface.

4. Do Not Let Cleaner Dry on the Brick

Always rinse before it dries. Dried cleaner leaves new haze, streaks, or crust.

5. Do Not Use Random Household Products

Avoid bleach, ammonia, colored soaps, or oily sprays. These can stain, strip sealant, or leave sticky layers.

When and How to Reseal Brick After Cleaning

Brick needs sealing after strong cleaning. Mortar haze removers, vinegar, and other treatments can strip sealant or dry out the surface.

When to Reseal?

• After removing heavy haze

• After using any acid-based cleaner

• After cleaning salt stains

• Before winter or wet seasons

• After noticing fading color or chalky spots

How to Reseal Properly?

1. Let the surface dry for 48 hours

2. Pick a sealer made for brick or masonry

3. Apply with a roller, brush, or sprayer

4. Cover joints and grooves evenly

5. Let the sealer soak in fully

6. Wipe away any puddles or drips

7. Let dry per product label

Bottom Line

Brick surfaces take on haze, stains, grease, and salt. Each type of mark needs the right method. Thin brick, full brick, and tile all clean up best with the right tools and steady work.

Use dry cloths, soft brushes, and simple mixes like vinegar or baking soda.

Bring in stronger products only when needed. Rinse fully. Dry the surface. Reseal if needed.

Stick to clear steps. Clean with care. Keep your brick looking the way it should.