How to Clean Dirty Bricks in a Fireplace

A fireplace is so cozy and relaxing, right up to the point you notice the very large amount of black soot built up on the front of the bricks.

Have you ever put on "blinders" to avoid being distracted by something? Well, I'm pretty good at it myself.

I had resigned myself to having to clean out the ashes in my fireplace- but cleaning the brick around the fireplace seemed like such a big job I had been putting it off for a very long time.

Now the grime was staring me in the face, and I couldn't put it off any longer.

So I pulled out my cleaning books, consulted with experts and found out the best ways to clean fireplace brick fast. Now I can relax knowing that even dirty soot can't ruin my relaxed mood.

So, if you are fortunate enough to have a real brick fireplace too, follow my tips to clean your brick and keep your fireplace looking great. Then you can relax too.

So, let's get busy cleaning!

What's The Problem?

Soot

Soot is a black powder made from incomplete burning of wood, coal, or other organic matter.

Even very small amounts of soot can cause problems by discoloring walls and ceilings which is called "ghosting". Soot is a tough thing to clean for 3 reasons;

1. Black carbon (ash) very easily stains most everything.
2. Smoke particles are very small and difficult to remove completely.
3. Soot has an oily base.

Brick

Bricks are made of clay that is shaped and then baked in a kiln to make them strong and durable.

Bricks can be sealed or unsealed. The inside of the fireplace is usually unsealed, some luck folks with shiny brick fireplaces have brick that is sealed with a penetrating Tung Oil. Sealed brick is more resistant to soot stains.

Soot will not stain as easily and usually comes off sealed brick with just soap and water. Use caution with using stronger cleaners on sealed brick to avoid stripping off the oil sealer.

Brick that has a dull, flat appearance is unsealed brick that is harder to clean because soot, dirt and grime can penetrate easily into cracks and crevasses.

Safety First

Before you tackle this job, there are a few safety tips when cleaning brick that you should follow:

• Wear rubber gloves to protect your skin. The brick itself, not to mention cleaners, can be hard on your hands.
• Use goggles to protect your eyes from any possible splattering. Dirt, grit, not mention cleaning solutions can cause severe eye damage.
• Always rinse chemicals completely from the brick before trying another cleaning solution.
• TSP in particular can severely burn your eyes and skin, so wear goggles, a long sleeve shirt and plan on showering after cleaning with it.
• Read the cleaning product instructions and follow all directions before using.
• Keep the room well ventilated. Open the windows, especially with using ammonia.
• Never mix cleaning chemicals with another.

Cleaning Tools

Get your supplies together before you start. It's more efficient and you won't have to stop in the middle of cleaning to get another item, possibly getting distracted, or dripping your cleaning solution on the floor, etc.

• Nylon bristle brush
• Sponge
• Paint brush
• Green scrubby
• Spray bottle
• Cleaning rags
• Vacuum cleaner or broom
• Drop cloth
• Rubber gloves
• Goggles

Prep Work

Prep work is very important to start getting your brick clean.

The easiest and most efficient way to start is to vacuum the brick wall, fireplace, fireplace surround, or floor to remove as much of the loose dirt and debris.

Because brick tends to collect dust and cobwebs, vacuuming is the best way to prepare the surface. This will eliminate the easily removed debris on both the top surface and in between the bricks so that you can proceed with the deep cleaning.

1. Lay a tarp down around the base of your fireplace to protect your carpet or flooring from debris or your cleaning solution splattering.
2. Use a vacuum with a brush attachment to remove loose dirt and dust (Use a broom if you have to). Once the brick gets wet, you want to avoid scrubbing any extra dirty water that you wouldn't have to.

Now that you have everything ready- get on those gloves and goggles and let’s get busy cleaning that brick!

Cleaning Methods

The cleaning solutions are listed in order of their chemical aggressiveness. I recommended that you start with the least aggressive method first and, if needed, work your way up to the heavy hitters. It's likely you won't need to use all of the cleaning solutions I have listed. But I've listed everything you should need for a thorough cleaning.

• Dishwashing liquid (like Dawn)
• Borax (like 20 Mule Team)
• Ammonia
• Trisodium Phosphate (TSP)

The trick of how to clean brick is part cleaning solution and part "elbow grease". The dirtier the bricks are, the more pressure you will need to use in order to clean the soot off the bricks completely.

If your brick is really, really dirty - I'd still clean it first with Dawn to remove the greasy grime, rather than proceeding straight to stronger methods like the TSP. You'll get better grease removal with the detergent to start off with.

Use caution if your brick is painted or sealed. Use less force when scrubbing and check your cleaning solution in an inconspicuous place to be sure it will not damage the surface.

And before I forget--Bristle brushes spatter cleaning solutions, so wear clothes you don't mind getting stained or grimy!

Method 1: Dishwashing Detergent (Like Dawn)

This is the easiest and quickest method to remove most dirt and dust that will not come off with a vacuum.

Dishwashing detergent is a degreaser which is great to remove greasy tar and smoke. Regular dish washing detergent is fairly safe and won't damage brick either.

Combine water and dish detergent cleaning solution in a spray bottle. Use a second spray bottle filled with warm, plain water and spray area to rinse.

Cleaning Solution:

• 1/2 cup dish detergent
• 4 cups hot water

Cleaning Process:

1. Spray cleaning solution on a small section of brick.
2. Scrub with a nylon bristle brush.
3. Rinse with clean water.
4. Dry with a clean dry cloth.

Method 2: Dishwashing Detergent and Salt

Salt is an inexpensive abrasive to provide some extra scrubbing power that plain detergent and water can't provide. Use this to scrub away extra stubborn spots that the dish soap and water won't clean off.

Cleaning Solution:

• 1 cup dish soap
• 1 cup table salt

Cleaning Process:

1. Mix the salt and dishwashing liquid into a paste.
2. Scoop some of the solution onto a rag and rub the solution into the brick.
3. Let the paste sit for a few minutes.
4. Use a green scrubby and scrub to remove the paste.
5. Rinse the brick thoroughly with clean water.
6. Vacuum up any salt debris.

Method 3: Borax and Dishwashing Detergent

Borax is a natural disinfectant, increases the cleaning power of detergents and is an anti-fungal and repels pests. It is odorless and alkaline which gives it its cleaning power. Borax produces a small amount of hydrogen peroxide when mixed with water so it acts a little bit like an "oxy" (oxygen) cleaner.

Cleaning Solution:

• 2 Tablespoons Borax
• 1 Tablespoon dishwashing liquid
• 4 cups hot water

Cleaning Process:

1. Put the Borax in a 32 oz. spray bottle and add 4 cups hot water. (Hot water is needed to completely dissolve the Borax.)
2. Shake vigorously to completely dissolve the minerals.
3. Add 2 Tablespoons of dish soap and swirl to mix.
4. Spray a section of bricks with the cleaning solution.
5. Scrub each brick with the nylon bristle brush or green scrubby. (The bristle brush will work best). Move the brush in a circular motion to get into all the cracks and crevices on the brick and mortar.
6. If the bricks are especially dirty, you may need to apply more pressure.
7. If you are having trouble removing the dirt, you may need to use more force when cleaning or select a stiffer brush.
8. After you scrub each brick or section of bricks, use a clean damp rag to wipe away the grime.
9. It may be necessary to repeat this process more than once.

You can optionally make this cleaning solution in a bucket and use a paint brush or sponge to apply to the brick.

Method 4: Ammonia and Dishwashing Detergent

Cleaning Solution:

• 1/2 cup of Ammonia
• 1/4 cup Dishwashing Soap
• 4 cups HOT water

Cleaning Process:

1. Put 4 cups of hot water in a spray bottle.
2. Add 1/2 cup of Ammonia and 1/4 cup dishwashing liquid and swirl to mix.
3. Spray a section of bricks with the cleaning solution.
4. Scrub each brick with the nylon bristle brush. Move the brush in a circular motion to get into all the cracks and crevices on the brick and mortar.
5. If the bricks are especially dirty, you may need to apply more pressure.
6. If you are having trouble removing the dirt, you may need to use more force when cleaning or select a stiffer wire brush.
7. After you scrub each brick or section of bricks, use a clean damp rag to wipe away the grime.

You can optionally make this cleaning solution in a bucket and use a paint brush or sponge to apply to the brick.

Method 5: Trisodium Phosphate (TSP)

TSP is a strong cleaning solution and is used often by profession smoke and fire damage cleaning companies to remove greasy grime, smoke and soot stains. You can purchase TSP sometimes at grocery stores, but it is most commonly found at home improvement stores.

TSP will stain and discolor metal, strip paint off walls, dissolve wall paper, and stain wood floors, and etch ceramic tile and natural stone floors.

TSP cleaning solution is stronger than the solutions above, so be sure to wear your rubber gloves and goggles for eye protection. Make sure you put down your tarp to avoid getting TSP carpet or flooring or any other surface.

TSP powder dust can irritate the nose, eyes and lungs. It is damaging to skin and eyes so be sure to wear protective gloves, eye protection and long sleeved shirts and pants when using.

Always check in an inconspicuous place first to make sure that you don't damage the surface.

Cleaning Solution:

• 1/8 cup TSP
• 1 gallon of hot water

Cleaning Process:

1. Mix 1/8 cup of Trisodium Phosphate (TSP) in 1 gallon of hot water.
2. Apply to the brick using a paint brush or soft sponge. Do not use the bristle brush to avoid spattering the TSP solution.
3. Rinse completely with warm water.
4. Repeat if soot or greasy stains remain.

Additional Stain Causes & Solutions

If you are still having problems, there are a few other solutions I didn't go into, because TSP should get rid of all of the grimy soot that can be removed safely to start with.

Red, orange, or brown stains could be rust stains, which need to be removed with a different cleaner called oxalic acid (super toxic).

Mold and mildew stains cause a green or black colored stain, but are only present in wet environments and can be removed with chlorine bleach.

A white hazy stain on the brick is called efflorescence. It's caused by water getting into the brick. This can be removed by using stronger abrasives like a pumice stone or muriatic acid.

There's just one other cleaner that is stronger than TSP and that can be used to clean brick. It's called muriatic acid. Muriatic acid is a chemical that is very hazardous- I wouldn't touch it with a 10 foot pole cleaning something inside my home.

If you have tried everything you can think of and the stains still don't come off, call a brick cleaning professional.

Your Brick Is Clean!

These are the best methods that you can use to clean a fireplace or any dirty brick inside your home.

All of these cleaning solutions have been researched, tried and verified. So, regardless if your lights are low or your room is bright and sunny, you can relax knowing that you can easily give soot the boot!

Image of the fire in a fireplace is courtesy of Max Wolfe, CC BY.