Basic rules for cleaning chimneys and fireplaces

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How to clean a chimney?

In order for the wood stove or fireplace to function properly, your chimney must be cleaned regularly. The soot, produced by burning wood, settles on the inner surface of the chimney which leads to a narrowing of its opening.

As a result, because of a thick soot layer, there is insufficient heating of the chimney walls and the draft is reduced and becomes insufficient. Due to this, carbon monoxide and smoke get inside the room and there is a risk of fire, as soot begins to burn in the chimney, and the pipe spits out sparks on the roof. The combustion of soot in the chimney can also cause mechanical damage to its walls. 

Even if the fireplace or stove has not been used for a long time and there is no soot in a chimney, there is a possibility that objects like spider webs, leaves, garbage, feathers, and bird nest twigs, have got into the chimney. Therefore, once every 6 months it is necessary to carry out the inspection and cleaning of chimney pipes. And remember that the best fuel for woodstoves and fireplaces are dry pots that have been lying in a dry place for at least a year and a half. But any fuel combustion is an oxidation process which requires two conditions: oxygen and high temperature. If at least one is missing, it leads to soot formation, as a consequence, insufficient oxidation of carbon. 

Traditional methods of cleaning chimneys

According to The Home Dweller, there are several traditional ways to clean a chimney. 

To prevent soot formation during the firewood burning, you can pour some rock salt on them. 

One of the most popular traditional methods of soot removal is the use of potato peelings. To do this, the stove or fireplace should be properly heated with at least half a bucket of potato peelings or chopped potatoes in the fire. This produces starch-containing steam which softens and decomposes soot, helping it come off the chimney walls. This ancient method is used as a preparation for mechanical cleaning. 

A good effect is obtained by burning a lot of aspen firewood in a wood stove. Cleaning of chimney pipes occurs as a result of achieving high temperatures and soot burning. When aspen firewood burns, a strong draft is formed, removing ash from the chimney. This method is quite dangerous, as high loads can lead to its destruction. If there is a lot of soot there, it is better to use safer methods. 

Chimney pipes can be cleaned mechanically and chemically. Let’s consider each method in detail. 

Basic rules of mechanical cleaning 

Time to call a chimney sweep? If you want your wood stove or fireplace to cause you no troubles, cleaning of chimneys is a mandatory regular procedure. However, the ammunition and tools of modern chimney sweeps do not resemble the classic image we know from Andersen’s fairy tales. To inspect the condition of a chimney and make sure there are no cracks and blockages, today’s a true chimney sweep even has a video camera in his arsenal. 

This method is cheap and simple and does not require any special skills. Remember those brushes they used for bottles’ cleaning? The same thing with chimneys. Only these wired brushes are larger, longer, and more rigid.

Many woodstove and fireplace owners prefer to clean their pipes on their own. Those interested in chimney cleaning methods should remember a few basic rules: 

A general chimney cleaning is required if the thickness of contaminants on the walls of exceeds 2 millimeters. Cleaning of the pipes can only be performed if it’s not raining or wind blowing, otherwise the roof may collapse. The insurance is a prerequisite. 

To prevent soot from entering the house during the cleaning procedure, all the cleaning openings and the fireplace door must be closed tightly. The firebox of an open fireplace must be covered with a large piece of dense wet cloth. 

Before cleaning, inspect the pipe to make sure there are no bird nests or any type of debris inside. If any, and you can’t reach it from above, use a stick to push it down the pipe. 

Modern chimney sweeps can control the pipes’ condition with a video camera.

Cleaning tools

The main tool for cleaning pipes today, as well as many years ago, is a wire chimney brush.

A wired brush must be inserted into a chimney and moved in reciprocating motion while rotating to more effectively clean the walls. In the case of any movement problems (if it is not associated with the bent pipe), most likely, the chimney pipe is very narrow and got clogged. Such congestion can be broken through with a heavy object tied to a rope that we talked about above. When the chimney is heavily clogged, you can use a combination of two methods – first, clean the chimney with chemicals, and then mechanically. Pre-prepared soot will be removed much easier and faster. Its diameter should exceed the diameter of a chimney by about 20 %. If you need to clean a rectangular or square structure, it is better to use a metal brush. The pipe is cleaned with a smooth up-down motion. 

You can also use a heavy round metal ball to remove congestion, e.g. thick debris or collapsed bricks. To break through the congestion, the ball, attached to the rope, is thrown right into the middle of the pipe hole, trying not to damage the walls of the chimney. If the blockage cannot be punched through in this way, part of the chimney has to be disassembled. The core’s diameter should be at least 2/3 of the pipe cross-section. Another purpose of the ball is the weighting agent, for this purpose, it is attached to the rope together with the wired brush. 

For more effective cleaning, a scrubber is used to clean a dense layer of soot before using the brush. 

Do not use sports weights or other heavy objects that are not intended for cleaning chimneys. Due to the shifted center of gravity, they can flip over and get stuck inside the pipe. 


  • An open fireplace with a direct hearth can be cleaned not from the roof but from the bottom (from the fireplace side). For this purpose, a brush with a long composite handle is used. 
  • After you have finished cleaning, carefully open all the cleaning holes and remove soot with a brush and scoop and then use a vacuum cleaner. 
  • At the very end of the procedure, open and clean the firebox and ash box. 

Chemical cleaning: preventive and general 

Cleaning of a chimney from soot occurs with a chemical reaction. During firing up, special products are added to the firebox which during combustion react with soot, soften its deposits, corrodes and softens it, resulting in cleaning the walls of the chimney. The variety of chemicals for cleaning chimneys is wide enough. It can be powder, briquettes of different shapes, liquids, etc. They are all non-toxic to humans and, of course, harmless to chimneys. 

Today, a large number of different chemicals are produced to prevent deposits on chimney walls. 

They contain substances that during the combustion process form non-toxic gases that destroy deposits on the inner surface of a chimney. These chemicals are produced in various forms: powders, liquids or briquettes. They are used only if the thickness of the deposit does not exceed 2 mm. 

Chimney soot removers reduce the weight and thickness of creosote deposits and help to prevent fires in chimneys.

The most widely used cleaning agent is a concentrated chimney sweep log. Mineral additives contained in it, form volatile substances when burnt, destroying deposits on the walls of a chimney. The product has a prolonged effect. As a result of combustion, the log becomes thinner, collapses, and falls into the firebox, where you can easily remove it. The log is used for cleaning any solid fuel wood stoves, fireplaces, and boilers. 

Like other chemicals, a chimney sweep log is a prophylactic agent and is only used if the pipe is slightly contaminated. Before use, you must remove the log from the package without removing the wrapper. Put it into the firebox, wait until the briquette lights up. If this does not happen, you need to fire up the wrapper on both sides. The active substance of the drug acts on the continuation of two weeks. During this time, soot falling may continue. After a two-week period, inspect the chimney and clean the furnace firebox. If the duct is heavily contaminated, the log can make the situation worse. At the time of lighting it, there’s a micro-explosion in the firebox, so if the stove is cracked, it can be partially destroyed.

Sediment, escaping from the chimney ducts, enters the heating unit which must then be cleaned manually.

Chemical agents do not replace regular inspection and chimney cleaning. If the stove or fireplace is not used more than once or twice a week, it is sufficient to carry out a chemical cleaning every 6 months. In the case of a daily fire, the fireplace is cleaned twice a season. A wood stove used for heating needs to be cleaned every 2 months. To keep the chimney ducts as clean as possible, the following simple rules must be observed: 

  • Do not burn household waste, especially plastic. 
  • Try not to burn coniferous wood all the time, as a large amount of resin forms a strong deposit on the walls of the chimney during burning. 
  • Do not use damp wood. High humidity leads to water vapors and soot formation which adversely affects the chimney condition. It is best to use dry hardwood. 
  • It is useful to add a few aspen or alder logs to the fire in the end. They form a high temperature and burn soot from the chimney. At the end of each insert, throw a few aspen billets into the fire to keep the chimney as clean as possible.

As mentioned above, the cleaning of a chimney is a mandatory regular procedure which is necessary for the safe and quality operation of the stove or fireplace. After the process, the inspection of chimney condition and repair (if necessary) is required. Chemical methods of cleaning are used for preventive purposes. Only traditional mechanical cleaning carried out by a professional can guarantee a 100% result. A true specialist will not only clean it but also check its condition with the help of special mirrors or video cameras. If you want your stove/fireplace to serve you for many years, entrust this work to professionals.

A fireplace or woodstove in the house is a source of special warmth, comfort, and inexpressible atmosphere. You just sit on a bear’s skin by the fireplace, throwing firewood inside the hearth, tucking in charcoal with a fire poker and enjoying your life. Central heating systems can’t keep up! Heating boiler sounds much less romantic, but it also has many advantages, as well as require more attention. All these products are very demanding in terms of care and use, ignoring and inappropriate compliance with the regulations can lead to serious consequences. The main rule is that a chimney must be “breathing” easily, thus, it must be periodically cleaned. 

Is it necessary to clean a chimney? 

The answer is unambiguous. Yes, it is. Let’s take a look at what a chimney actually is. As the name suggests, it is a kind of device for the smoke flow. It is a vertical channel with a round or rectangular cross-section designed to exhaust the products of fuel combustion into the atmosphere. A chimney creates a natural draft that makes the necessary air enter the hearth and removed gas from it. Fuel does not burn completely without residue (soot) which rises up into the chimney together with the smoke. It settles on the walls of the chimney, forming a deposit, which over time becomes thicker. The diameter of the chimney decreases and so does the draft, thus, the chimney stops to perform its basic function. To avoid this, soot removal is required periodically. In the past, when there was a widespread woodstove heating, chimney sweeps were very popular. There are professional chimney sweeps these days too, but you can cope with the process on your own. 

Why a chimney gets dirty? 

Soot formation is a natural process but there is a number of factors that affect the degree of soot pollution and its spreading speed, e.g.

  • The use of low-quality fuel. Raw, muddy wood increases the soot amount, as well as soot from coniferous wood is more sticky, penetrating, and worse cleanable due to its resin content; 
  • Litter burning (yes, some people throw plastic bottles and bags in their fireboxes); 
  • Poor-quality chimney brickworks with problematic areas or just a narrow pipe; 
  • Low-temperature resistance. 

Safety instructions

All methods require mandatory compliance with safety regulations. 

For mechanical cleaning: make sure you have insurance when working on the roof; do not clean the chimney in bad weather when it’s raining, strong wind, icy roof, etc.

For chemical cleaning: carefully read the instructions and stick to them. The fact is that different means are used differently and all the nuances are very important – whether or not to remove the wrapper; if there is a need to vent it after cleaning or not; should you close your firebox tightly, etc. Be sure to read all the instructions before use. 


A chimney must be cleaned regularly with a frequency of once every 6 months. Cleaning the chimney may be needed before, it is easy to guess about it by the following signs: 

  • Smoke color changes. Dark smoke indicates that soot is burning on the walls of the chimney, which means that cleaning is necessary. White smoke comes out of the clean pipe. It can also be light and transparent. When soot accumulates, it ignites, changing the color and consistency of the smoke which becomes dense and dark. You can notice a change in the color of the flame in the oven. If the chimney is clean, the flame is light orange. The appearance of a saturated dark orange hue indicates that the time has come to clean the chimney. 
  • Low draft. Cleaning a chimney is not a difficult process, but it is rather labor-intensive and requires consideration of many aspects. And if you have a chimney that needs cleaning, and there is no desire to understand the process thoroughly, then it is better to entrust the cleaning to professionals, as a dirty chimney is extremely dangerous (carbon monoxide poisoning and high fire risk).


Author bio: Roy is a literary enthusiast, a loving father of twins, a programmer in a custom software company, editor in chief of, greedy reader, and a gardener.


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