Candle Soot: How To Fix It And Prevent It

candle soot

We all love burning candles, but sometimes burning candles along with little tufts of black smoke and black smudges on the containers, our walls, and even our ceilings. What is candle soot?

Candle soot is the black smoke released into the air due to an incomplete burning process. Candle soot is the result of the hot wax traveling up the wick not burning thoroughly enough, resulting in partially burned hydrocarbons being released into the air.

When you light a candle, the melted wax is drawn up into the candle wick, further keeping the flame alive by fueling a chemical reaction.

The process involves the combustion of the carbon present in the wax with the air’s oxygen to produce carbon dioxide and steam.

When this chemical reaction is altered, incomplete, or imbalanced, it releases smoke consisting of unburned carbon atoms that are carried within the steam. As the steam rises, it appears as black smoke, or candle soot.

Candle Soot

Candle Soot Causes

As stated above, candle soot is caused by incomplete combustion of the carbon in the wax with the oxygen present in the air. Below are the different factors behind the formation of candle soot. What causes candle soot?

Candle soot is caused by the candle burning improperly, which may be due to the candle being in a drafty area, too many wax additives, an improper wick size, or a wick that has not been trimmed. In addition, candle soot can be caused by using additives such as mica and crayons when making the candles.

Let’s take a closer look at some of the causes.

Wax Additives

While the length of the wick and any disturbance of the flame are the chief factors that produce soot, it mostly occurs when too many scents or other additives are blended into the wax, further affecting the natural combustion of the candle. Certain fragrance oils are also likely to increase the amount of soot produced by a candle.

Flame Flicker

A flickering flame changes the amount of wax being used at that moment. Excess flickering leads to more consumption of wax and incomplete burning of the carbon with the oxygen. When uneven quantities of carbon are expelled into the air, you get a black soot deposit.

Wick Material

While cotton-core wicks don’t produce soot, zinc-core candle wicks are more likely to yield dark smoky soot into the air.

Lack of Air Flow

Container candles, especially glass jar candles, may produce candle soot when the candle starts to get closer to the bottom. The closer the flame gets to the bottom of a candle, especially a jar candle or a glass candle – its access to oxygen also decreases. This makes the flame to change in size, which changes the flow of liquid wax up the wick, further releasing unburned carbon atoms into the air as soot.

Clogged Candle Wick

There are times when the candlewick gets clogged due to too many additives in the wick, further preventing the absorption of wax at a consistent rate up into the wick. This changes the combustion and releases the unburned carbon into the air, thereby yielding soot.

Wrong Wick Size

If the wick is the wrong size, it again leads to unbalanced chemical reactions and produces too much carbon that’s further released in the form of black soot.

Preventing Candle Soot

Whether it’s the time of candle production or the moment when you actually light the flame, there are a few simple measures that can prevent the production of candle soot. How to prevent candle soot?

Prevent candle soot by extinguishing a candle that isn’t burning properly and trimming the wick. The wick should be trimmed every four hours that the candle is burning and it should be trimmed to 1/4 of an inch. In addition, make sure the candle is on a flat surface with no drafts to move the flame.

Let’s look at some more tips designed to help you stop candle soot from becoming a problem.

Tips for the Candle Burner or User

  • Place Cappers on Jar Candles

If you are using jar candles with open tops that are around 3 inches in diameter, make sure you put caps on them. Burning down into the glass makes jar candles produce more soot as it advancing towards the bottom. Installing jar cappers minimizes turbulence by separating the rising hot air from the falling cooler air.

  • Trim the Candle Wick

The ideal length for a candle wick is one-fourth of an inch, so make sure to trim the same to this size before actually lighting the candle. If it still produces soot, trim it even further until you get a clean flame.

  • Don’t Move the Candle Much

Make sure you don’t disturb the flame once the candle is burning. The best idea is to place the candle where you want it and then light the flame, or simply blow it out before you move it to another spot.

  • Keep the Candle at a Distance from Flammable Items

Always place the candle at a safe distance from the walls, drapery and other flammable objects. Keeping it at least a feet away from the walls avoids soot marks on the surface.

  • Keep Candles Out of Drafty Spots

Candles are likely to produce soot when they are burnt near air vents, open windows, or fans. While a still flame uses fuel at a constant rate, a flame that’s bouncing with the breeze draws up fuel at a variable rate. The size of the flame shrinks when extra oil is drawn into the wick, thereby leading to incomplete burning of the fuel. As a result, the candle expels the excess oil into the air in the form of soot.

  • Install an Air Filter

It’s a good idea to install a nice air filter that collects all dust particles, impurities and other debris in the air, thereby avoiding soot deposits.

  • Check for Mushrooming

Make sure to blow out the flame and trim the candle wick when it starts to mushroom at the top. Re-light the flame once you remove the black soot ball on the wick.

For the Candle-Maker

  • Avoid Heavy Scents

Scented candles tend to produce lots of black soot. The fragrance oils present in scented candles are mostly unsaturated hydrocarbons in liquid form. This makes the wax softer instead of burning when hot, further producing more soot when the candle cools down. Plus, fragrance-containing candle waxes have higher oil concentration in the air which leads to more soot.

  • Use Cotton Wicks

Cotton wicks yield less soot than most other wicks as they are likely to burn cleaner. They not only absorb wax properly, but also produce less carbon as compared to other materials.

  • Use Wax with High Melting Points

It’s essential to go for wax that comes with high melting points as a cooler burning flame is likely to yield more soot. The fact that the chemical reaction remains incomplete results in more carbon releasing into the air.

Removing Candle Soot

There are numerous ways to clean candle soot, but you need to make sure to wear a mask, rubber gloves, and safety glasses before getting started. Not wearing the right safety gear may lead to harmful carbon and harsh chemicals in soot hurting your eyes or skin. Also, wear old clothes to make it all a lot more hassle-free. How to remove candle soot?

Remove candle soot by vacuuming as much excess soot off of the surface as possible, then wipe the stained area with a dry magic eraser until most of the soot has been removed, vacuum the area again, then dab at the area with a cotton ball using rubbing alcohol or vinegar.

Do not rub on the area using a wet sponge or cotton ball because it may remove some of the surface paint and make the affected area look even worse.

Cleaning Soot Off of Walls and Ceiling

  • Vacuum the Walls

You can use a vacuum and a dusting brush to remove larger soot particles. You need to hold the vacuum at least one-half inch from the wall or ceiling to absorb all the dust and other loose soot particles. Avoid touching the surface to prevent smearing of the soot.

  • Use a Soot Sponge or Dry Cleaning Sponge

You can clean the soot deposits on the wall using a chemical sponge without any water. You will easily find rubber sponges in the stores that don’t call for water to pick up the soot when wiping the wall. Simply wipe the surface in a downward motion, while making sure not to scrub the wall as it may end up in spreading the stain even more. Begin from a small area and gradually advance across the wall or the ceiling.

  • Use a Sponge and Wet Cleaning Solution

If the above methods don’t seem to work, you need to go for a strong cleaning solution that contains a degreaser. A solution of de-greasing dish-washing liquid and water work just right to get the task done. Dip a sponge in the cleaning solution, further wiping down the wall or ceiling in directional strokes and not scrubbing, rubbing, or going for a circular motion to clean the soot.

Another good cleaning solution is vinegar mixed with water. Make sure to use enough water to dilute the solution otherwise it may leave a visible cleaning mark on the wall or the ceiling. It’s also a good idea to dip the sponge in some rubbing alcohol, further cleaning the surface following the dab and blot method.

  • Go for a Final Rinse and Dry the Surface

Once you have performed thorough cleaning of the walls or the ceiling, dip a clean sponge in fresh water and wring the same to drain excess water. Once it’s damp, wipe down the surfaces with the same, further drying the ceilings and walls using a lint-free microfiber cloth.

Cleaning Soot off of Glass

Usually, glass candle holders seem to be a trouble when it comes to getting rid of the soot deposits. How do you clean candle soot off of glass?

Clean candle soot off of glass by using a damp paper towel or cloth using water or alcohol after you have extinguished the flame, and allowed the wick and wax to cool down. In addition, you can take the glass or candle holder and soak it in warm soapy water before washing and rinsing clean.

Also, remove any soot or black smoke from the surface of the candles by rubbing them with a soft cloth dipped in rubbing alcohol.

Candle Soot Dangers

It’s a very natural phenomenon to form a small amount of soot when it goes under incomplete combustion. And that’s why, in small amounts, it’s not dangerous when it comes to health risks. However, in some situations, it can be. Is candle soot dangerous?

Candle soot can be dangerous if you leave the candle burning for several hours while you are sleeping. It can fill your bedroom with soot and even fill your lungs with soot causing respiratory issues and even asphyxiation. This is why it is important to never leave candles burning unattended.

Which Candles Produce the Least Soot?

While all candles produce some soot, certain varieties are likely to yield more of the black smoke than others under the same given conditions. Which candles produce the least soot?

Soy candles release the least amount of soot into the air and are generally considered to be the safest candle to burn. Since soy candles are made from all-natural soybean oil that has been treated to become wax, it is far less toxic than paraffin wax which is a petroleum byproduct.

Frequently Asked Questions

Does Goo Gone remove soot?

Goo Gone is an oil-based cleaner and should not be used on most surfaces. In fact, Goo Gone can do more harm than good on surfaces that consist of fabric, paint, and wood. These surfaces can absorb the oil and make the problem even worse than it already is.

How do you get soot out of curtains?

Sprinkle a dry absorbent such as baking soda on the stain and let stand for several minutes before vacuuming off. Blot at the stain using a sponge and dry cleaning solvent until the solvent is absorbed. Repeat the process as many times as necessary to remove the stain and then wash as suggested.


In conclusion, sometimes candle soot can be a real problem, but it is a problem that is easily solved and prevented. You can avoid candle soot entirely by following the manufacturer suggested burning practices for your candles.

Make sure you keep the wicks trimmed, keep the candles away from fans and windows and don’t let the candles burn longer than 4 hours at a time.

With these simple steps, you won’t have any problem enjoying your candles.

Candle Soot Prevention

Carl Adamson

Hi, I'm Carl Adamson, one of the founders here at Candleers. A few years ago I got really into the art and craft of candle making, initially with soy wax container candles. My friends started asking me to make candles for them and pretty soon it turned into a nice side-business. I started this website as a way to document what I've learned over the past few years and hopefully help others in the process. I still love candle making but I'm learning that what I enjoy even more is the business side of things - and for this reason I've started consulting others on how to start and grow their own candle-making businesses and side-hustles.

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