How to Clean Chimney Brick
Dirty chimney bricks can dull your home’s sparkle
Your chimney works hard to keep you warm in the winter, so it’s no wonder it can start looking dirty after a few uses. Cleaning chimney bricks helps keep the inside and outside of your chimney looking good and decreases the risk of a house fire. Here’s how to clean chimney brick like a pro—and when to actually call in a professional instead to tackle this project.
Why Do I Need to Clean Chimney Brick?
Wood-burning fires produce soot and creosote, which accumulate on the interior chimney brick and can become a safety hazard. Creosote is a flammable substance that can catch fire when it’s left to build up, and that fire could spread to your home if not caught immediately. Cleaning creosote buildup off the bricks in your chimney box can help prevent fires.
The bricks outside of your chimney, on the other hand, are exposed to the elements daily, leading to a buildup of smoke, moss, and other grime that looks unsightly. Cleaning the chimney’s exterior bricks can help them look like new.
How Much Does It Cost to Clean Chimney Brick?
Cleaning chimney brick is an affordable project since you can use items you already have around the house, like dish soap or vinegar. However, keeping bricks clean isn’t the only chimney maintenance you’ll need to do to keep the chimney clean and safe. Hiring a chimney sweep costs $130 to $380, or an average of $255. It’s important to schedule a full chimney cleaning once a year to maintain the entire structure, inside and out.
Signs You Need to Clean Chimney Brick
It’s one thing to know that you should clean chimney bricks, but it’s another to know when to do it. Here are a few common signs you need to clean your chimney bricks:
The chimney bricks have visible stains or discoloration.
There are white stains (called efflorescence) on your exterior chimney bricks.
You notice signs of mold or mildew, especially on exterior bricks in a shaded or damp area.
There’s a buildup of soot or creosote inside the fireplace.
The chimney damper appears to be black.
You spot oily residue on the fireplace walls.
How to Clean Chimney Brick
The method you use for cleaning chimney bricks depends on whether the bricks are interior or exterior. You’ll also need to take extra care with older bricks, which are more prone to damage than newer ones. If in doubt, contact a professional to help you with this task.
Clean Out the Fireplace
If you’re cleaning interior bricks, the first step is to clean the brick fireplace and firebox. You should only clean inside your fireplace when it’s cold, so if you’ve recently had a fire, wait for it to cool off completely. Then, remove the ashes and dispose of them in the garbage. Once you’ve removed most of the ashes, vacuum the firebox using the brush attachment on your vacuum cleaner.
Saturate the Brick With Water
Whether you’re cleaning interior or exterior bricks, you must get them wet with clean water. If you’re cleaning inside, put down a drop cloth to prevent damage to the hearth or flooring. Use a masonry sponge to apply the clean water directly to the bricks until saturated. This helps keep the cleaning solution on the surface of the bricks rather than absorbing into the brick and potentially causing damage.
Scrub Gently With a Mild Cleaner
Now comes the cleaning part. First, use the mildest cleaner to see whether it will remove the dirt from the bricks. If any stains remain, use a slightly stronger cleaner. Generally, a mixture of water and cream of tartar is the mildest option. Some mild cleaning solutions are easy to make at home using a base of water and adding ingredients in the following ratios:
¼ cup of dish soap to 4 cups of water
Equal parts of vinegar and warm water
2 tablespoons of borax to 4 cups of water, plus 1 tablespoon of dish soap
½ cup of ammonia to 4 cups of water, plus ¼ cup of dish soap
You can also buy cleaners specifically designed for cleaning fireplace brick, though this is usually a more expensive option.
Whatever cleaner you choose, use a firm-bristled brush to work it into the brick’s surface from top to bottom. Once you’ve scrubbed them, wipe them down to remove excess cleaning solution.
Use Harsh Cleaners Sparingly
You might encounter mold and mildew if you’re cleaning exterior chimney bricks. Bleach can help remove these stubborn stains, but you must take precautions. Goggles and rubber gloves are a must. Mix one tablespoon of chlorine bleach with a gallon of warm water and scrub the stains gently using a brush.
Your chimney might also have white stains, called efflorescence, on the brick. To remove these stains, mix ⅛ cup of trisodium phosphate (TSP) and a gallon of water and apply to the brick, scrubbing with a firm brush.
If your chimney bricks are still stained, muriatic acid should be your last resort cleaner. This is the harshest cleaner, so it’s essential to try removing the stains with milder cleaners first. Muriatic acid can remove stubborn stains—but it can also damage the brick if misused. Sealing the brick after using muriatic acid can protect it from damage. But if you reach this stage and still have stains, calling a pro might be your best option.
Rinse Thoroughly to Remove Excess Cleaner
The final step is to rinse the bricks. If you’re cleaning exterior bricks, use a garden hose to rinse them thoroughly and let them dry.
If you’re cleaning interior chimney bricks, dip a sponge into a bowl of clean water and gently dab them to wash away the cleaner. Change the water if it becomes dirty, and repeat until all the bricks are clean.
Tips for Cleaning Chimney Brick
Cleaning chimney bricks keeps them looking good both inside and out and also helps reduce fire risk. Here are a few tips to keep your chimney brick in tip-top shape:
Use a mild cleaner to scrub the brick—especially for older or more fragile bricks.
If the first cleaner you try doesn’t get rid of the grime, try a slightly stronger one. Never go right to the most potent cleaner, as it could cause damage.
Once clean, thoroughly remove the cleaner from the bricks. Allowing the cleaning solution to soak into or dry on the brick can damage the surface.
Schedule an annual chimney cleaning with a chimney sweep.
DIY vs. Hiring a Pro
Cleaning mild soot and creosote buildup on interior chimney bricks can be a simple DIY project using supplies you already have. Cleaning exterior chimney bricks can also be a DIY-friendly project if you’re comfortable using a ladder and walking on the roof. Removing stubborn stains can take some elbow grease and patience.
Hiring a local chimney cleaning pro is safer if you need to clean bricks on the exterior portion of the chimney. Professional chimney cleaners have the tools and safety equipment needed to work on the roof, whereas the average homeowner likely doesn’t. And if you need to clean inside the chimney flue, hiring a pro is an absolute must. A chimney sweeper can thoroughly clean your chimney and will also identify any problems, such as loose bricks or crumbling mortar, that need attention. It’s recommended that you clean your chimney once a year using a professional chimney sweep.
Frequently Asked Questions
Depending on the amount of soot present, you can vacuum some of it using a brush attachment on your vacuum cleaner. Then, remove the leftovers with a mild cleaner, such as dish soap or vinegar mixed with water. Before applying a cleaning solution, saturate the bricks with clean water to prevent the cleaner from penetrating beyond the surface and causing structural damage to the bricks.
Yes, brick chimneys should be cleaned by a professional chimney sweep once a year. You can spot-clean the bricks throughout the season using a mild cleaner, but it’s not required unless the chimney bricks are especially filthy.
The best way to clean creosote from brick is to hire a professional chimney sweep. However, you can use a creosote log to remove excess buildup between cleanings. You can also clean minor creosote buildup using dish soap or vinegar mixed with water.
A chimney cleaning brick or log can help loosen creosote between professional chimney cleaning appointments. Although they can help keep your chimney cleaner, they are not a substitute for chimney sweeping and are not meant to be used regularly.
The best way to clean fireplace bricks is to use a mild solution on saturated bricks. An equal mixture of water and vinegar or a drop of dish soap in a bowl of water can help remove grime from fireplace bricks. Make sure you wet the bricks thoroughly before applying the cleaner and rinse them after you’re done to prevent damage.