Construction of a stove pipe (chimney) made of brick and metal. How to assemble a chimney Chimney pipe diagram
All efforts to arrange your country house can literally fly down the drain if that very pipe is poorly designed and made. Reverse draft will cause smoke and fumes. Or the roof elements will become hot, which will lead to a fire. The efficiency of your stove or boiler depends on the chimney. Therefore, you need to have a good understanding of the structure of a steel chimney and competently approach its manufacture with your own hands.
What is a chimney and how does it work
The chimney is one of the main components of your heating device, be it an antique brick oven or an ultra-modern gas boiler. Your safety and budget depend on the free passage of flue gases through the chimney: with a well-designed and constructed chimney, the stove consumes much less fuel. Previously, chimneys were built by professional stove builders. Current technologies make it easy to do this yourself. Of course, you need to study the issue and carefully follow the drawing and manufacturing procedure.
What materials are they made from?
Chimneys are made of bricks or pipes; the latter are divided into chimneys from of stainless steel, from iron sheet, asbestos-cement, fireclay, glass. Let's look at their design, advantages and disadvantages, and the ability to maintain even traction without jumps.
Brick
The most traditional of all. Advantages: durability; powerful thermal inertia: they immediately provide good traction, and when warming up, they adapt to the operation of the stove; will never give reverse thrust or its pulsation. Disadvantages: unsuitable for boilers, may result in burner flame failure and accident; a rectangular cross-section gives an uneven flow of gases, combustion products settle more strongly; difficult to build and repair; require a foundation due to heavy weight.
Ancient brick pipe with sleeve
Pipes
This is a much more practical type of chimney that can be used in all cases. Depending on the material, the pipes are different.
Asbestos cement pipes
Advantages: round; lungs; cheap; easy to install. Disadvantages: low heat resistance (used for furnaces with low flue gas temperatures, up to 300 0); it is difficult to make a curved structure (rubber couplings - bad decision); porous structure; rapid contamination by soot and, as a consequence, the possibility of its ignition.
Asbestos cement pipes in a stack
Ceramic
They consist of several parts: a chimney made of refractory ceramics, thermal insulation and a concrete body. Advantages: durable; round and smooth inside, so no need to clean them; have thermal insulation and tightness, fire resistance and heat resistance; easy to install; Suitable for any boilers, stoves, fireplaces. Disadvantage: expensive, difficult to repair and difficult to connect into a curved structure.
Ceramic pipe assemblies
Glass
Advantages: even more chemically neutral and even smoother than ceramic; durable. Disadvantages: expensive (100 times more expensive than steel); the rest are the same.
Fragment and chimney made of glass from Schott - Rohrglas
Polymer
Are used only for sleeves. Advantages: easy to install, lightweight, flexible, cheap, durable. Disadvantages: fragile and cannot withstand high temperatures.
Polymer chimneys for fireplaces FuranFlex RVW
Lining - insertion inside an old, usually brick, chimney liner in the form of a polymer, flexible metal corrugated or metal pipe for chimney restoration.
Lining of brick chimneys with FuranFlex RVW polymer pipes
Steel
Steel chimneys are optimal in terms of price, quality, and ease of installation.
Types of steel structures
There are two main types of chimneys according to their orientation relative to the heating device: straight (attached) and side (attached).
Straight chimneys
They are placed above the heating device, indoors and pass through the internal ceilings and through the roof. Most often, this is the best solution specifically for stoves. Advantages:
- Acid condensation does not fall out, or falls out only slightly, but the ease of passage of gases through a straight chimney is important.
- Less soot deposits, easy to clean yourself, and therefore less fire hazard.
- Works well without a gate draft regulator.
- Only the pipe on the roof is visible on the house, this is aesthetically pleasing.
Flaws:
- Passing through floors and roofs is more difficult than through a wall.
- Large unevenness of thrust, pulsating and even reverse thrust during gusts of wind. Therefore, for modern boilers with an emergency shutdown device, such a chimney is not suitable, even if equipped with a complex deflector.
A straight chimney passes through the ceilings and roof
Side tie-downs
The axis of such a structure does not coincide with the axis of the heating device. Advantages:
- Installation outside the house with a single passage through the wall.
- Ease of construction.
- The presence of a container for collecting acid condensate, completely eliminating its flow into the heating device.
- Even with the simplest fungus it works stably in strong winds, and if a deflector is mounted on it, the draft will always be direct and stable.
- Makes it possible to precisely regulate thrust due to low thermal inertia. This will always ensure optimal fuel consumption.
Flaws:
- In cold weather, condensation can turn into ice and burst the container. The container may freeze up to the tee, which will block the draft. Hence the need to place a container for condensate inside the house.
- The place through which the chimney exits to the outside is designed as a passage unit. But in winter, the unit absorbs moisture from the air, and the insulation can cake and settle. Then thermal stress will accumulate in the upper part of the assembly, which can cause a serious crack in the wall.
- The weight of a chimney, unlike an attached one, lies on the passage unit; this can also affect the insulation and cause the phenomena described above.
- Cleaning is quite difficult due to the bends of the chimney. A specialist is required.
A side, or attached, chimney runs along the outer wall of the house
Lateral internal
However, side chimneys can be located both inside the house and in the thickness of the wall, then contact with the roof cannot be avoided.
The difference in attached chimneys - outside and in the wall
No one type of chimney can definitely be called the best. Each of them is good in its place and depends on the conditions: type of heating device, roof structure and floor beams, wall material and type of chimney (single-wall or sandwich). The advantage of the attached side chimney is that in this case there is no need to go through the roof. But it is completely excluded in the case of single-wall pipes due to the cold in winter.
Types of materials
Steel chimneys are made of black steel, low-alloy steel and galvanized iron
Black steel
This is a simple carbon steel without alloying additives. Advantages:
- The cheapest
- Low contamination with soot and easy to clean
- In terms of installation qualities - exactly like steel
- Does not require a foundation for installation.
Flaws:
- High thermal conductivity leads to the fact that the gases quickly cool down and a lot of condensate is formed, which must be removed
- Pipes get very hot, so they require special structures where they pass through walls and roofs
- It is impossible to make an external chimney due to lack of thermal insulation
- In terms of durability, it is much inferior to a steel pipe (service life is only about five years), as it is subject to severe corrosion
- It has low heat resistance - it burns out quickly in high-temperature flue gases.
Black steel chimney parts
Attention! To increase the service life of a black steel chimney, you need to make minimal amount joints and use thick-walled pipes.
Low alloy steel
It belongs to ferrous metals, but it contains additives of nickel, chromium and molybdenum in quantities equal to those in stainless steel. Advantages and applications: the same as for pipes made of black steel, but low-alloy steel corrodes more slowly.
Galvanized iron
This is the worst of the three previous options. The zinc layer burns out very quickly, and the thin, unprotected iron begins to corrode and collapse.
Galvanized iron pipe is the worst of all options
Stainless steel
Stainless steel is heat-resistant and resistant to acids - combustion products. Such chimneys are durable and strong; resistant to temperature changes, corrosion, condensation; inexpensive, easy to assemble due to its modularity, which allows you to build a system of any complexity; easy to repair; smooth inside, so soot does not settle, and the chimney requires almost no cleaning; They have a low heat capacity, so heating any stove is easy: a stable draft immediately appears. They also come in several types, depending on the alloy of the steel used for the pipe and the design.
Corrugated steel pipes
These flexible metal pipes are made from steel strip and are used for sleeving only. Their service life is limited due to the uneven surface, on which combustion products deposit more strongly: soot, acids.
Corrugated metal pipes - used only for lining brick pipes
Single wall stainless steel pipes
Their wall thickness is usually from 0.6 to 1 millimeter. Advantages - like all non-corrugated ones metal pipes, but these are much more durable than the others. The disadvantages are the same as those of non-corrugated metal pipes.
Details of a single-circuit steel chimney
The disadvantages of single-wall pipes can be eliminated by a simple design improvement: the manufacture of an insulated steel pipe, or a sandwich chimney. Their advantages:
- Thermal inertia is greater than that of single-wall pipes - flue gases pass quickly, but cool slowly, so little soot and aggressive condensate are formed
- When passing through floors and roofs, there is no need for overly complex thermal insulation units, since such chimneys heat up less
- External installation, without passing through the roof, is possible
- Installation is generally quite easy
Flaws:
- Sandwich pipes are noticeably more expensive than single pipes
- Completely unsuitable for brick kilns. A stove with such a chimney will produce reverse draft during gusts of wind.
But since people are now concerned about the efficiency of their heating devices and traditional ovens are rare, sandwich chimneys have become widespread.
Stainless steel sandwich pipes
The design of a double-layer chimney and its distinctive features
This is a structure of two steel pipes inserted into each other, different in diameter. The outer one is called the casing. A pyre-resistant insulation is placed between the pipes, usually basalt wool (laid so that the fibers are oriented along the pipe) 30–35 millimeters thick, capable of withstanding heat of a thousand degrees. Mineral wool is completely unsuitable.
Sandwich chimney parts
Making a sandwich chimney with your own hands
Comprehensive instructions on all aspects of the construction of chimneys can be found in SNiP 41–01–2003. Here are the main ones:
- One chimney - for one heating device.
- The inside of the pipe must be free of burrs and irregularities that provoke turbulence in the gas flow.
- It is unacceptable for the pipe to come into contact with utilities. Approximation is allowed up to one hundred and twenty centimeters if there are no flammable materials between the pipe and communications.
- The pipe can approach building structures by a maximum of 38 centimeters, and its passage through them must be designed as a fire-fighting unit at 38 centimeters on all sides.
- Sagging of pipe sections is eliminated.
- Each bend must be performed using several bends so that it is smooth.
- The pipe is rigidly fixed to the wall, the step of strengthening the brackets is no more than 1.2 meters.
- There must be cleaning hatches, at least one.
- The top of the pipe is equipped with a deflector.
- The chimney should rise at least 60 centimeters above a flat fire-resistant roof and a meter and twenty centimeters above all others.
We see that the best option for most of our heating devices is a double-layer pipe. Such a chimney can be completely installed with your own hands. You can even do it yourself for this purpose. This requires some preparation and calculations.
Selection of pipe material and calculation of basic parameters
Calculation of the cross-section and height of the chimney
This is done quite accurately according to a schedule called a nomogram. The square and rectangular icons on the chart indicate a rectangular or square channel; in this case, the cross-section value is multiplied by a coefficient. But this does not concern us. But in the case of a round channel, the nomogram overestimates the required value, since the installation of the gate is taken into account. We look and record the relationship between the power of the boiler (stove), the diameter and height of the chimney.
The nomogram shows the diameter and height of the attached chimney
There are some rules:
- Height is the vertical from the stove to the top of the chimney, any horizontals and diagonals are not taken into account.
- It is better to avoid narrow, tall pipes; they are more likely to produce draft pulsations.
- For low-power devices up to 10 kW, it is better to choose a narrow and low pipe that is safe in terms of wind, since the gas pressure is weak and will not prevent back blowing.
Selecting the desired design
You must also have basic welding and tinsmithing skills and submit a drawing. For example, we chose the left chimney in the figure and, knowing the power of the boiler or stove, calculated its required length using the nomogram. For example, it is equal to 12 meters.
Detailed design of two chimneys - attached and attached
Approximate required finished parts
We must remember that we can make sandwich pipes, deflectors, and clamps ourselves. But most of the related parts - such as elbows, tees, brackets - will be easier to buy. It will be easier to buy a deflector.
Chimneys are assembled from a mass of parts
Table: materials required for construction
| Position | Name | Marking | Quantity | Approximate price per piece | approximate price |
| 1 | Boiler connection | ADP | 1 piece | 2100 rubles | 2100 rubles |
| 2 | Muffler | SILDP | 1 piece | on request | on request |
| 3 | Pipe with pyrometer and gate | TPDP | 1 piece | 2700 rubles | 2700 rubles |
| 4 | Elbow (abduction) 45 0 | CDP45 | 2 pieces | 3450x2 rubles | 6900 rubles |
| 5 | Tee with plug 45 0 | TTDP45 | 1 piece | 7300 rubles | 7300 rubles |
| 6 | Plug with condensate hole | PRDP | 1 piece | 900 rubles | 900 rubles |
| 7 | Tee with revision | TIDP | 1 piece | 7500 rubles | 7500 rubles |
| 8 | Main mount | SMDP | 6 items | 1100 rubles | 6600 rubles |
| 9 | Wall mount | BMDP | 1 piece | 1100 rubles | 1100 rubles |
| 10 | Elbow (abduction) 30 0 | CDP30 | 1 piece | 3100 rubles | 3100 rubles |
| 11 | Elbow (abduction) 15 0 | CDP15 | 1 piece | 3100 rubles | 3100 rubles |
| 12 | SDP | 1 piece | 2700 rubles | 2700 rubles | |
| 13 | Spark arrestor | CI | 1 piece | 2000 rubles | 2000 rubles |
| 14 | Crimp clamps, bolts with nuts and other metal fittings | according to need |
What is a deflector?
Conventional pipe fungus does not extinguish smoke, and in strong winds it does not help against the occurrence of backdraft, therefore it is unsuitable for modern boilers. A deflector is ideal for all occasions, and the best of the deflectors is the TsAGI deflector, developed by scientists at the Zhukovsky Central Aerohydrodynamic Institute. It can handle wind speeds of up to 200 kilometers per hour. It must be fixed with self-tapping screws so that it does not fall off.
TsAGI deflector assembly
What steel will be needed for pipes
Ideally, the inner and outer pipes should be made of different grades of steel. The internal one should have a lower coefficient of thermal expansion and much greater chemical resistance and heat resistance. Mechanical strength not so significant. The outer one should be mechanically stronger and just as resistant to corrosion as the inner ones - but for a different reason. If the inner pipe must resist heat and aggressive acids, then the outer pipe must resist rust. And its thermal conductivity must be maximum so that the pipe does not fatally heat up where it passes through the floors and roof.
Grades of sheet steel for chimneys are designated by an alphanumeric index, in which the first digit indicates which of the sandwich pipes the steel is intended for: 3 - for a single-wall or internal pipe; 4 - for external.
Table: types of steel and their purpose
| Name | Purpose | t 0 | Designation | Note |
| General purpose steel | For boilers long burning and economical stoves | up to 800 0 | 316 | |
| General purpose steel | For fireplaces and gas boilers | 304 | Replaces the previous one, but cheaper | |
| Heat-resistant steel | For any heating devices | up to 1000 0 | 310S | |
| Highly plastic steel | For single wall and corrugated pipes | 321 | Replaces all of the above, but expensive | |
| General purpose steel | For any heating devices except solid fuel boilers and chimneys in bathhouses | up to 800 0 | 430 | Used with grades 304 and 316 |
| High-strength steel, chemical and heat resistant | For solid fuel boilers and chimneys in bathhouses | Used with 316, 310S or 321 |
Determination of steel sheet thickness
Steel sheet thickness for external pipe should be between 0.6 millimeters (steel 409) and 0.8 millimeters (steel 430); For the inner pipe, the thickness of the corresponding steel (for inner pipes) depends on the device. For gas boiler- from 0.6 millimeters, for liquid fuel appliances - from 0.8 millimeters, for solid fuel appliances - from 1 millimeter.
Important! The quality of the steel for the inner pipe does not affect the determination of the sheet thickness! The required sheet thickness depends only on the characteristics of the device to which the chimney is being built.
Determination of the area of the steel sheet and the amount of insulation
The sandwich pipes we need internal diameter 200 millimeters, and external ones - 250 millimeters will need to be made in quantities: 330 millimeters long - 2 pieces, 500 millimeters long - 2 pieces, 1000 millimeters long - 10 pieces. We will make the simplest calculation of the area of these pipes based on the diameter. For example, for the inner pipe: 3.14 x 200 = 628; plus a small reserve for connecting the sheet into a pipe, let it be 650; multiply by the length of all pipes according to the calculation - 650 x (330 + 330 +500 + 500 + 1000 x 10) = 7.579 m2.
Sectional view of a sandwich pipe with a clamp and insulation
The area of a typical steel sheet is 1,250 x 2,500 mm. Respectively. we need to purchase 4 sheets of steel 430 for the casing (average price - 780 rubles per sheet) and 3 sheets of steel 316 (average price - 8800 rubles per sheet) for the inner pipe. Ideally, you can buy a couple of sheets of ordinary structural steel for partitions when insulating.
The insulation corresponding to the diameter of the inner pipe of 200 millimeters will be 25 millimeters thick. We will need a package of Rokwool Floor Butts basalt wool 1000x600x25 mm (8 pieces per package) with an approximate cost of about 800 rubles.
Basalt woolRokwoolFlor Butts
In addition, we will need heat-resistant and roofing sealants and fiberglass mesh or fiberglass.
Heat-resistant sealants can withstand temperatures up to 1500 degrees
Table: Required materials
Required Tools
- Welding machine (if you have skills)
- Metal scissors
- Shoe knife
- Hammers
- Kiyanka
- Pliers
Pipe manufacturing
All of the steels mentioned are easily processed by hand. But you cannot join the sheet into a pipe using a regular fold, as when making pipes from galvanized iron.
Incorrect chimney pipe seams
Such a seam is not at all airtight, and through it acids from the flue gases (through the inner pipe) and moisture from the atmosphere (through the casing) leak into the insulation. Therefore, it is better to weld the seams (with argon-arc welding or electric welding) - if you know how to do this. If not, then all seams must be thoroughly sealed with heat-resistant sealant.
Properly assembled sandwich - pay attention to the folded seams
Insulation is done in stages according to the drawing. Basalt wool is wrapped and separated by partitions. Then everything is wrapped with fiberglass mesh and tied with soft wire to make it easier to put on the outer pipe.
Insulation of sandwich pipes
Chimney assembly
- We don't need a foundation; all support brackets will be attached to the wall.
- We connect the boiler and pipe using an adapter.
- A gate has already been installed in the first factory section of the pipe. A condensate trap is connected. In our project, we still decided to do it inside - so that the condensate would not freeze. We install a tee with an inspection hatch for cleaning soot (“pocket”) and a condensate collector. We provide easy access to the pocket.
First steps to assemble a chimney
- We prepare a hole in the wall with a diameter of at least half a meter: we install a system of stops, install a pipe, lay non-combustible insulation into it, and cover it with the same insulation.
Chimney passage through the wall
- We pass our sandwich through the pipe. We close the hole on both sides with non-flammable asbestos sheets. There are ready-made passage units different sizes, and it might be easier to use a ready-made one.
Connecting a chimney pipe manually
- As the pipe is assembled, its connections are secured with clamps and coated with sealant, and section by section are secured to the wall with brackets in increments of no more than 1.2 meters using anchor bolts. Deviations from the vertical should be no more than 3 millimeters per linear meter chimney. The distance to the wall is at least 15 centimeters.
Sandwich chimneys on a brick wall
Such a chimney needs to be cleaned approximately once every three months, but mechanical method It's better not to use it at all. In severe cases, you need to call specialists. And your destiny is chemical cleaning. This is a substance in the form of a briquette or powder, which, when burned in the firebox of a boiler or stove, releases chemicals that dissolve soot and other deposits in the chimney.
Chimney sweep powder for cleaning chimneys
Video: how to properly attach a chimney to the wall of a house
The large list of what you have already done for your beloved home now includes a sandwich chimney.
Removing gases and smoke from heating appliances is one of the main components of ensuring comfort and safety. It is not enough to choose the chimney you like in the photo in a private house; it is important to take into account the possibility and nuances of its installation. The efficiency of removal of combustion products from stoves, fireplaces, gas, liquid and solid fuel boilers depends on the correct installation. Study the requirements and become familiar with the standards, even if you do not plan to do the work yourself.
The most popular configuration of a modern chimney in a private house
Basic requirements for chimneys
The chimney is designed to remove combustion products and create draft during the operation of heat generators. It must be resistant to high temperatures, moisture and sulfuric acid formed upon contact flue gases with condensate. The walls of the pipeline should be smooth so that less soot accumulates.
Requirements for the installation of chimneys are regulated by special state regulations: SNiP 41-01-2003; VDPO (Rules for the performance of work, repair of furnaces and smoke ducts); SP 7.13130.2009.
The main ones are the following:
- the cross-sectional area of the chimney or channel must be greater than or equal to the area of the heat generator outlet pipe;
- at the base of the channel it is necessary to arrange a pocket 250 mm deep for cleaning and/or a pipe for removing condensate;
- you cannot use more than three turns;
- the pipe must be rotated with a radius of rounding no larger than the diameter;
- connecting elements at intersections building structures prohibited;
- the length of the horizontal section is allowed a maximum of 1 m;
- bends and tees should not bear the load from the elements located above them;
- if the roof structure contains flammable materials, a spark arrester with a cell no larger than 5x5 mm must be installed on the head of the pipe;
- When working with a natural gas heat generator, the head must always be open without umbrellas or other coverings.
Gas exhaust system design
What should be the height of the chimney?
A necessary condition stable and reliable operation Almost all heat sources depend on the presence of good draft. It occurs due to the difference between the temperatures of the exhaust gases and the outside air. As this difference increases, craving increases. It directly depends on the height, characteristics and correctness of the chimney.
The action of the wind can enhance the natural draft in the pipe, or it can interfere. At favorable conditions horizontal wind flows, colliding with the chimney, change their direction and move from bottom to top, as a result, a vacuum is created at the outlet, and combustion products are literally sucked out of the chimney. If there are other obstacles, the wind can be directed from top to bottom and create a reverse movement of gases - reverse draft, which leads to smoke in the room.
Scheme for determining the height of the chimney
The normal movement of the wind can be interfered with by any tall structure located nearby, including part pitched roof. Therefore, the height of the chimney is determined taking into account the distance to the ridge according to the regulatory scheme.
In this case, the total height of the pipe from the heat generator must be at least 5 m, for a gas boiler - at least 3 m.
Features of chimneys made of different materials
A chimney in a private house can be made of the following materials:
- brick;
- ceramics;
- steel.
It is impossible to give preference to one of them and select a clear favorite. Right choice suitable material for the construction of a chimney can only be done taking into account a complex set of influencing factors. First of all, it is necessary to analyze the specifics of operating conditions, the properties of each material and prices at the time of comparison.
Stove ceramic chimney
Scope of application of a brick chimney
A brick chimney is usually less expensive than other smoke removal systems. It can withstand high temperatures and even soot fires. Its main disadvantage is the bulkiness and complexity of the design. Built on a foundation or reinforced concrete floor. When working with stoves, fireplaces and wood-burning boilers, it is very reliable and durable, since the high temperature of the flue gases prevents the formation of condensation. In other cases it quickly collapses.
Brick chimney from fireplace
To build a brick chimney in a house with your own hands, you must have the special skills of a stove maker and mason. The trunks should be free of cracks and any irregularities. This is a serious construction that requires qualified workers.
Restoring a brick chimney can be done independently. You just need to insert a special flexible corrugation of the appropriate length into the channel from above.
Stainless steel chimney inside a brick pipe
Advantages of using ceramic chimneys
A ceramic chimney is also relatively inexpensive. It is characterized by increased strength and the ability to accumulate heat. High fire-resistant properties allow its use in high-temperature systems of solid fuel heat sources. The ceramic pipe can withstand heat up to 1200°C when soot ignites. The service life with proper care is equal to the service life of the building.
Ceramic elements of different sizes are connected using special grooves and sealed with fire-resistant adhesive-sealant. Ceramic pipes can be installed openly and in shafts made of bricks or special hollow blocks, installed inside and outside the house.
Ceramic chimney pipes
For new construction, it is very profitable and convenient to use system chimneys made of ceramic pipes laid in special shafts. They are a good solution for all types of fuel combustion equipment.
Characteristics and types of steel chimneys
A steel chimney is easily assembled according to the principle of a designer. A wide selection of shaped and fastening parts allows you to create almost any configuration and install a chimney in a private house, both during construction and during the operation of the building.
Taking into account the requirements for resistance to corrosion and acids, pipes are made not from ordinary steel, but from galvanized or stainless steel. Stainless steel is noticeably more expensive, but has a longer service life.
The scope of application of steel products is limited to systems with relatively low flue gas temperatures, since according to SNiP 41-01-2003 they Maximum temperature– 500°С. Accordingly, use with solid fuel boilers undesirable.
Steel smoke removal systems are very convenient for installation in already occupied houses, as they are installed quickly and do not require a foundation, plaster or cladding. At the same time, they are noticeably more expensive than brick and ceramic ones.
Chimneys with two walls are also made from steel, using the “pipe-in-pipe” principle. They are called coaxial. These are used for condensing and turbocharged gas boilers with closed chambers combustion. The air required for combustion is taken not from the room, but from the street.
Coaxial chimneys according to inner tube combustion products are removed, and combustion air is supplied through the outside. Their assembly is carried out similarly to single-wall steel ones. Installing a coaxial type chimney has the lowest cost.
Coaxial chimney installation kit
Necessity and methods of insulation for a chimney
A safe chimney design requires its insulation. Pipelines must be insulated to protect against possible freezing of condensate. In addition, retaining heat in the chimney increases the efficiency of all types of fuel-burning equipment.
Ceramic pipes are wrapped with mineral or basalt wool. The same insulation can be applied to an old asbestos-cement pipe, enclosing it in a galvanized steel casing. Can be used to fill the gap between an asbestos-cement pipe and an expanded clay casing, broken bricks or other hollow material filled with cement mortar.
Insulation of ceramic pipeline
The most cost-effective option for protecting a steel chimney is to use foil-coated mineral wool insulation.
It allows you to quickly and easily insulate not only a new, but also an existing pipe. The result, however, is short-lived, since regular exposure to wind leads over time to fraying of the insulation, and wet cotton wool ceases to be a heat insulator.
Sandwich chimneys, which already contain a layer of insulation, do not have this drawback. Moreover, they are as easy to assemble as single-wall steel ones. The widespread use of this particular option is limited only by cost.
Elements of an insulated sandwich type chimney
Very good choice is the installation of a chimney in a private house from ceramic pipes in a steel casing, which combines the advantages of ceramic and double-walled steel systems. It is suitable for absolutely all heat generators, but is still rarely found on the domestic market.
Quite good results are obtained by a more economical folk method of making an insulated chimney: the pipe is assembled from galvanized steel, wrapped with mineral wool and enclosed in aluminum corrugation. It turns out to be a homemade “sandwich”. This is certainly troublesome, but noticeably cheaper than standard ready-made solutions.
Economy version of a metal chimney of the “sandwich” type
Procedure for installing a metal chimney
Every person who has ever assembled a construction set can figure out how to make a chimney in a private house from galvanized or stainless steel. Components modern systems metal combustion product outlets are simply inserted into each other. The joints are sealed with heat-resistant mastic or sealant and secured with clamps.
Installation starts from the bottom, that is, from the heat generator. The connection is made “through condensate” against the movement of flue gases. This will prevent condensation from flowing out and possible icing of the chimney.
Performing a pipe passage through the roof
If the chimney passes through the roof, then to protect it from precipitation, use an adjustable metal apron with an inclination angle corresponding to the roof (0-15°, 15-30°, 30-45°). If the pipe rises above the roof by more than 1.5 m, then it must be fixed using guy wires.
Fastening the chimney and passing through the roof with the installation of an apron
To seal the intersection of the chimney with the roof, you can use universal rubber seals. Depending on the slope of the roof, a straight or angular type is used. It is only necessary to take into account the range of their operating temperatures.
Chimney passage through the roof with Master Flash sealant
The procedure for working with a universal rubber seal is very simple. It is necessary to cut the top in accordance with the required diameter, put it on the pipe, coat the bottom well with heat-resistant silicone and attach it to the roof using a screwdriver.
Installation procedure for universal rubber seal
With steep roof slopes, there is a risk of damage to chimneys from snow avalanches. To protect pipes when snow slides off the roof, you can install special metal dividers, as shown in the photo of a chimney on the roof of a private house.
Metal dividers to protect against snow sliding
Pipe passing through a wall
To avoid difficulties associated with creating an opening in the roof and its subsequent sealing, they usually try to use a chimney outlet through the wall, usually the back one.
This option implies only one intersection - with outer wall, which is easily isolated polyurethane foam, in contrast to the obviously complex and unreliable connection of a hot chimney to cold roof. In this case, the pipe is easily attached to the outside of the wall, does not affect the interior and is guaranteed to be free of leaks.
Checking the chimney before use
After completing the installation of the chimney, be sure to check the presence of draft. This is very important point, regardless of whether the chimney was installed in a private house with your own hands or with the help of specialists. Violations made during installation can lead to poor traction or even reverse traction. This is fraught with the accumulation of carbon monoxide in the room, which poses a direct threat to the life and health of residents.
- The draft can be checked using a mirror by placing it in the area of the smoke hood and pointing it towards the chimney. With good traction, it does not fog up.
- It is convenient to use a flame from a burning match, paper or candle. If the flame deviates in its direction when approaching the chimney, then everything is in order, otherwise operation is unacceptable.
To check the tightness of the joints and the absence of dangerous heating of structures adjacent to the chimney, a test firebox is carried out. At the beginning of operation, there may be an odor and slight smoke due to the evaporation of residual oil and crystallization of the sealant.
During further operation, its condition should be checked at least once a year and cleaned before the heating season.
It is important not to forget about cleaning
To summarize, we should once again dwell on when and which chimneys are best to use:
- For wood stoves and fireplaces during the construction of a house - brick or ceramic;
- for wood-burning stoves and fireplaces in an inhabited house - ceramic in a steel casing;
- for gas, liquid fuel and pyrolysis boilers - system (ceramic or steel pipe inside brick channel) or steel insulated “sandwich” type.
Install the same as in the photo steel chimney Almost every man can do it in the house with his own hands if he takes a responsible approach and follows the above recommendations. A preliminary consultation with a specialist is guaranteed to protect you from dangerous mistakes.
Video: Types of chimneys
One of the main components in the heating system is the smoke exhaust channel. Installing a chimney in a private house is a rather complex and important process, since not only the proper functioning of the heating device, but also the health of the residents of the house depends on proper operation.
Installation of a boiler chimney in a private house
The functions of the chimney are to remove harmful products that are released during the combustion of fuel along with smoke, so it is impossible to allow at least part of these substances to leak into the room.
Another, no less important, factor in the arrangement of a chimney is its fire safety. It is necessary to ensure its correct passage through the floors and roof, and also to isolate it from walls built of flammable materials. By following all the rules when constructing this heating communication, you can achieve its excellent performance on long years, of course, carrying out annual preventive maintenance.
Everything must be done in such a way as not to get further problems with regulatory organizations, and also to feel completely safe, and for this it is worth studying the mandatory norms and regulations for the design and operation of chimneys of heating devices. This is especially true for brick stoves and fireplaces.
- The oven must have its own foundation. This condition is important because this structure should not depend on other foundations of the house. In the event of shrinkage or other unforeseen movements of the soil, the distortion of the general foundation may lead to a violation of the masonry of not only the stove, but also the chimney. The appearance of seemingly minor and unnoticeable cracks can pose a serious threat to the health of residents.
- The blower hole must be at a height of at least ten centimeters from the floor, as it must provide a sufficient flow of oxygen, thereby ensuring normal combustion of fuel and draft in the chimney.
- For fire safety purposes, the stove must be located at least 25 centimeters from the building walls made of flammable materials. And the best option would be to insulate the walls with heat-resistant materials.
- When installing internal structure stoves, where the chimney with smoke exhaust channels actually begins, it is necessary to strictly follow the layout of the rows. Blocking at least one of the channel openings can threaten the house with smoke with all the ensuing consequences.
- The stove body itself should be 35-40 centimeters below the ceiling. Next comes the chimney pipe.
- It is very important to arrange the correct cutting of the chimney passage through the attic floor. Brick protrusions should have steps seven centimeters high before entering the ceiling and after exiting the groove in the attic.
- If the attic floor is insulated with flammable insulation materials, a sand layer of at least five to seven centimeters must be laid on top of them.
- When fireproofing in the attic, the distance from the inner wall of the chimney to combustible materials must be at least 50 cm. For this purpose, the chimney skirt is laid out, which is located directly in the attic floor.
- The wall thickness of a brick chimney pipe should be 12–15 centimeters.
- If the pipe comes out on the roof on at a distance of more than three meters from the ridge horizontally, its height should be no more than 10 degrees along the slope from the horizon. If the pipe is located at a shorter distance, it should rise above the ridge by at least half a meter.
- These rules are provided by fire safety services and must be strictly observed.
Chimney for metal stoves and boilers
Chimneys for cast iron stoves are simpler in structure and come in two types:
- The first of them, shown in the figure, is more complicated than the second in execution, since it passes inside the building through all the ceilings. The procedures for arranging it in the roof and waterproofing the seams around the pipe will be especially labor-intensive.
But the advantage of this chimney is that it retains more heat in the rooms and that it can also heat the second floor or attic through which the pipe will pass.
- The second option for the chimney metal furnace is a structure that runs almost entirely along the street. Only part of it remains inside the house, which is fixed horizontally. This is a branch section from the heating device, which can be straight or in the form of a so-called elbow. It exits through the wall onto the street and enters a vertical chimney that rises parallel to the wall. Such a device is safer, and the pipe will not take up excess space in the room. Its arrangement will not cause trouble with waterproofing on the roof and its passage through the ceilings.
But when making such a design, the pipe for it must be selected with a thicker thermal insulation layer, which can reach a thickness of up to 10 cm. Without such insulation, the smoke in the pipe will quickly cool down, the draft will decrease, and condensation may also form, which is extremely undesirable for the stove .
Parts for metal chimney
If earlier in order to make a decent chimney you had to tinker a lot or spend a considerable amount on ordering a tinsmith, today manufacturers of ventilation and heating systems They produce finished parts of various configurations.
Such chimneys are available in different diameters, heights and insulation thicknesses. In addition, other accessories necessary for installing a smoke exhaust system on the wall and protecting it from moisture getting inside are also sold. Sample list parts intended for this purpose:
- Pipes of different lengths, equipped with special locking grooves for fastening them to other structural parts.
- Metal corner transitions made at different angles.
- Crimp clamps in various sizes.
- Mounting brackets
- Floor, wall and ceiling stands and pipe passages.
- Tees also made at different angles.
- Deflectors, fungi, spark arresters and thermal fungi.
- Connecting elbows with the required angle range.
- Other small parts required for chimney installation.
Important components in the chimney device
It is very important to correctly design the most complex components of the chimney - its passages through the attic, interfloor covering, roof, and also through the wall if the main pipe runs entirely along the street.
Interfloor and attic floors
The most difficult thing is to correctly route pipes through ceilings, walls, and roofs.
The chimney passage in the ceiling, made of wood, is framed with special pipes that isolate it from flammable materials to prevent them from igniting. The pipe has a larger diameter than the pipe, so when they are connected, a gap is formed, which also helps protect against overheating.
Chimney passage through the ceiling
There must be a distance between the chimney and the ceiling in which it is necessary to place foil or asbestos non-flammable material, the thickness of which should be at least 7-9 cm. The foil insulator is laid with foil inside.
The pipe is solid. Place of passage through wooden ceiling covered with a metal flange
It is important to remember that at the point of passage in the ceiling, the pipe cannot have joints, but must be continuous.
The same thing - on the floor
If a pipe is intended to pass through a room on the top floor, then a casing should be arranged around it, with holes for ventilation through which hot air will flow into the room. They are usually drilled out from the top and bottom of the casing. Such protection is needed in order to avoid accidentally getting burned on a very hot pipe while firing the stove.
On the ceiling and floor of the second floor, where the pipe passes through the ceilings, metal parts of the flange pipe remain, which cover the flammable materials of the floor and ceiling.
Passage through the wall
The passage of the chimney pipe through the wall is designed in the same way as through the ceiling, using special pipes placed on the chimney, which will help isolate flammable materials from high temperatures. Also, the section of the pipe that will be located in the wall is wrapped in a heat-resistant material with a thickness of at least 7-10 cm.
Roof passage
The most difficult place is the pipe penetration through the roof. He demands special attention in work, since the safety of the sheathing and insulation from external moisture, as well as the general fire safety of the house, will depend on it.
To do this, waterproofing is installed around the outside of the pipe using a special tape or a “penetration” on the flange, which is secured with adhesive-sealant and screwed on top with self-tapping screws.
Particular attention to thermal insulation of the roof structure
To prevent overheating of the sheathing, the pipe must be wrapped in heat-resistant material and pass through a metal panel from the inside of the roof.
The final stage of chimney installation is to install an umbrella on top of it, which will protect against dirt and water getting inside.
Conditions for normal operation
The design should:
- effectively remove gaseous waste from fuel combustion;
- be safe and comfortable for home;
- have good traction;
- withstand high temperatures;
- be protected from moisture and condensation;
- be resistant to external aggressive environments.
Chimneys can have a square or cylindrical shape, the latter is considered optimal, since it is less susceptible to the accumulation of soot and soot.
Other parameters that are also indicated by building codes:
- alloy steel parts made for the installation of chimneys are distinguished by anti-corrosion qualities and are thick in in 0.5 cm;
- the diameter of the pipe should be the same size as the furnace pipe or be slightly larger;
- chimney arranged for brick oven, is equipped with pockets that are located in the lower part of the smoke exhaust channels and have a depth of 20-25 centimeters. Doors are installed on them, through which soot deposits are removed;
- a metal chimney cannot have more than 3 turns;
- the turning radius of a metal chimney cannot be larger diameter pipes;
- the pipe must have a height of at least five meters.
All these conditions will help create normal draft in the chimney and effective removal of combustion products hazardous to health.
A short video tutorial on installing a chimney in a private house
It must be remembered that the choice of a chimney does not depend on its external data, but on the stove on which it will be installed, as well as on the fuel used and other heating parameters. Therefore, before purchasing or constructing a chimney, you must consult a specialist.
And one more warning - for some inexperienced builders there are an abundance of requirements for arrangement stove heating and chimneys - in particular, may seem like unnecessary “nit-picking”, which you can, if you wish, ignore. Believe me, these rules were developed by life itself, based on centuries of experience and careful engineering calculations. It’s sad, but more than once their neglect has been paid for with human lives.
The technology for laying a brick chimney itself is quite simple and understandable, since, unlike the brick stove itself, the pipe usually does not have internal channels that are complex in configuration. However, despite the relative simplicity of the design, one cannot ignore the colossal importance of this section of the stove, since the quality of heating of the house and the safety of both the building itself and the people living in it directly depend on it. Therefore, in order for all the work to be crowned with success, it is necessary to approach it with the utmost care, relying on recommendations experienced craftsmen and on developed and tested design schemes.
When erecting a chimney, you should remember that the evenness of the internal walls of the channel is no less important than the aesthetics of the external masonry. Not only the stability of the required draft in the stove depends on this circumstance, but also the duration of operation of the chimney without cleaning, since the smoke rising through the pipe leaves a much smaller amount of fuel combustion waste on smooth walls, without protruding mortar and deep seams, and the channel becomes overgrown much slower.
What types of brick chimneys are there?
Chimneys of brick stoves may have different types, depending on the location of their installation, the design of the furnace, and also on how many heating devices will be connected to the pipe. Thus, there are three main types of chimney brick pipes: mounted, root and wall.
- Mounted chimneys . The most widely used designs are mounted pipes. They are good because they are compact and do not take up any space. additional area indoors, but are simply a vertical extension of the stove.
They are erected on top of the last row of bricks covering the stove, around the left hole. Then the pipe is passed through the attic floor, attic, rafter system and rises above the roof.
- Root chimneys . This type of pipe is installed in cases where it is planned to connect a metal stove, or several heating devices located on one or even several floors.
In addition to metal ones, brick ovens can also be connected to such a pipe. This type of chimney is especially convenient if it is necessary to build two stoves in the house in adjacent rooms. For example, for a kitchen you need a stove with hob, and for the next room - only heating. In order not to lay out a separate pipe for each of them, a main chimney is built between the rooms, to which both heating devices are connected. Not only two, but also three or four stoves located on different floors of the house can be connected to a pipe of this type. In any case, it is necessary to very accurately calculate the size of the internal chimney channel, otherwise normal draft may not be ensured when several devices are operating simultaneously. The answer to the question why may be different.
- Wall chimneys they are built near the main (external or internal) walls or built into them. They can be used, just like main ones, to connect several furnaces located on different floors of a building.
The convenience of this design lies in the fact that it is located outside the residential premises, without occupying their space. For example, on the first floor of a house a fireplace can be built and connected to a wall chimney (there the pipe will be more similar in structure to a mounted one), and on the second floor a smoke exhaust pipe of a metal stove can be cut in (the same as in the version with a root pipe).
The disadvantages of this chimney option are the considerable cost of the project and the labor intensity of the work. Firstly, the construction of this structure will require much more building material. Secondly, the chimney, if it is partially on the street, requires serious insulation measures, otherwise winter period, with temperature changes, condensation will form in the internal channels, which will significantly reduce the efficiency of the heating device. Therefore, if this chimney option is chosen, then it would be more prudent to sacrifice the space inside the premises and run the pipe along the internal wall of the house.
Parameters of brick chimneys
Main sections of a brick chimney
A brick chimney is divided into sections that have their own purpose and are named differently. These features must be clarified immediately so that in the future it will be easier to understand the description of the pipe construction work.
1 – Pipe head. When laying out this part of the chimney, the bricks are moved to the outside to create a kind of “canopy”, as if hanging over the lower sections, partially protecting the walls of the pipe from precipitation.
2 – The neck of the pipe is located immediately below the head and has the same perimeter throughout its entire height, without protrusions, expansions or narrowings.
3 – “Otter” has more complex circuit masonry, since it has a protective function. Firstly, the “otter” masonry hanging over the gap formed at the junction roofing material and the walls of the pipe, closes it from the penetration of precipitation, and forms a space for the installation of waterproofing material. Secondly, its expanded walls become a guarantee of safety - at the point of passage through roof covering Due to the increased thickness, the required level of thermal insulation is created.
4 – A metal or other sheet (apron), mounted at the bottom of the otter, forms a kind of flashing that covers the joint between the brick wall of the pipe and the roofing material.
5 – “Fluff” - this is the expanded part of the pipe, located in the area where it passes through the attic floor. The walls of the “fluff”, like those of the “otter”, are thicker than others flat areas chimney - this is necessary for fire safety, since the attic floor very often consists of flammable materials, and their overheating must not be allowed.
6 – Roof covering design.
7 - The riser is a straight section of pipe that has smooth masonry throughout its entire height and is located in attic space from "fluff" to "otter".
8 – Attic floor.
9 – An umbrella cap is often attached to the top of the head, which will protect the internal channel of the chimney from water and debris getting into it.
You might be interested in information about what it is
The main function of the chimney is to effectively remove combustion products from the combustion chamber into the atmosphere. To do this, the chimney pipe is connected to numerous channels located in the stove structure, with which it must interact harmoniously. If the stove and chimney are built correctly, in accordance with the developed parameters, then when operating the heating device, good draft should be created inside the ducts, which will facilitate the timely removal of smoke to the street. However, at the same time, this should not lead to the heat generated by it literally flying out of the furnace. In a word, everything needs a “golden mean”.
Chimney channel section
To select the correct parameters for the cross-section of the chimney channel, you need to take into account the power of the stove, as well as the size of the combustion chamber. Smoke exhaust ducts will remain clean longer if their inner walls are made smooth, without protrusions or sagging of solution.
For this reason, during brick laying, excess masonry mortar protruding in the seams must be cleaned off not only from the outer walls, but also from the inner walls. Some owners of houses equipped with fireplaces or stoves use another way to achieve smooth channel walls - they install inside a brick chimney ceramic pipe called a tab.
The advantage of this design is not only that the insert has absolutely smooth inner walls. It is round in cross-section, that is, it has no corners, which means that smoke flows will not encounter obstacles in their path and will not create unnecessary turbulence and the “backdraft” effect.
On the right, the illustration shows the “ideal” movement of the flow of hot gases, which in a round pipe are twisted into a regular spiral and do not encounter resistance.
In addition, you need to take into account the fact that large-width chimneys, which are still installed in old houses, often have poor draft. This occurs due to the fact that the air heated in the furnace in a large space inside the pipe quickly cools down, which leads to the formation of condensation, which contributes to a decrease in draft, as well as smoke in the premises, and rapid overgrowing of the channel with soot. To heat a stove with such a chimney pipe design, you will need to use too much fuel. Therefore, it would be most rational to correct them by dismantling the wide upper part of the chimney, then narrowing the shaft and installing a round or square with rounded corners, ceramic, metal or asbestos insert into it.
Now from the form - to the linear parameters. The size of the internal cross-section of the chimney duct is one of the most important characteristics, since the efficiency of the furnace directly depends on this. The correct ratio of the power of the heating device and the cross-sectional dimensions of the pipe must be observed. Another guideline for determining the correct size of the channel can be the opening of the blower door - the cross-section of the pipe in any case should not be smaller than the blower hole.
The cross-section of the chimney shaft, relative to the size of the combustion chamber window, can be determined as follows. For fireplaces with an open firebox, the chimney opening size is on average 1:10. However, depending on the cross-sectional shape and height of the pipe, this indicator may vary in one direction or another. Approximate values of the channel cross-sectional area (in percent) are given in the table below.
Ratiof/F in % (f – cross-sectional area of the chimney channel;F – combustion chamber window area)
| Pipe height, m | Sectional shape of the internal channel of the chimney pipe | ||
|---|---|---|---|
| ROUND | SQUARE | RECTANGULAR | |
| 5 | 11.2 | 12.4 | 13.2 |
| 6 | 10.5 | 11.6 | 12.3 |
| 7 | 10 | 11 | 11.7 |
| 8 | 9.5 | 10.5 | 11.2 |
| 9 | 9.1 | 10.1 | 10.6 |
| 10 | 8.7 | 9.7 | 10.2 |
| 11 | 8.9 | 9.4 | 9.8 |
It is clear that in addition to the size of the firebox window, it is also necessary to take into account the reasonable height of the pipe - for example, a huge 10-meter pipe on the roof of a small, squat country house would look completely ridiculous.
The calculation itself is simple. According to the table, based on the height of the pipe and the shape of its internal channel, it is determined optimal ratio f/F. Then, based on the area of the combustion window, it will not be difficult to determine the area of the chimney channel. Well, then, using geometric formulas, all that remains is to bring the resulting value to linear dimensions– the diameter for a round pipe or the length of the sides for a rectangle.
This calculation algorithm is implemented in the calculator below.
The efficiency and performance of the stove depends on the optimal cross-sectional size and height of the chimney. SNiP rules and several calculation options will help you choose the right size for a wood-burning stove in your home.
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Why do you need to know the diameter?
Beginners do not understand the importance of the chimney cross-section for a stove and why it is so important to correctly calculate not only the internal size, but also the height of the pipe. During development individual project For autonomous system heating residential or production premises, the level of traction and performance of the unit depend on the accuracy of the data.
Inexperienced builders can make a pipe with a large or insufficient cross-section. In any such option, the operation of the heating device is disrupted, and you are simply throwing money away. For optimal operation of the home heating system, it is important to carry out an accurate calculation and familiarize yourself with the recommendations of regulatory documents.
Important! Fire safety home, work productivity, comfortable temperature– the solution to all these issues depends on the correct determination of the dimensions and length of the chimney.
What should be the diameter of the chimney for a stove?
The size of the chimney can be calculated in several ways. The simplest one is to determine the cross-section of the chimney depending on the size of the combustion compartment. Consumption solid fuel is determined by this characteristic, and based on these data the volume of exhaust gases can be determined.
If you have open view The firebox and chimney are made of a steel round pipe - these values should be in a ratio of 10 to 1. For example, the dimensions of the combustion chamber are 50/40. Such a stove must be equipped with a chimney with a cross-section of 180 mm.
If we make a pipe from brick, its internal size should exceed the size of the ash pan or ash door by one and a half times. The minimum size of a square cavity for gas removal is 140/140 mm.
Calculation methods
Exact method + formula
Calculating a chimney for a stove is not a task for beginners. It is better to entrust such work to professionals. But if you decide to calculate this parameter yourself, you will need knowledge of basic data and several formulas:
- B is the combustion rate coefficient of solid fuel. This value is determined based on the data in table No. 10 of GOST 2127;
- V – level of volume of fuel burned. This value is indicated on the tag of the industrial device;
- T – heating level of exhaust gases at the exit point from the chimney. For wood stoves - 1500.
- The total area of the chimney. It is calculated based on the ratio of gas volumes, this value is designated “Vr”, and the speed of their movement in the pipeline. For a household wood-burning stove, this number is 2 m/sec.
- The diameter of a round pipe is calculated using the formula - d² = (4 * Vr) / (π * W), where W is the speed of gas movement. It is better to perform all calculations on a calculator and carefully enter all values.
Calculating the optimal amount of thrust
This operation is performed to control the calculations of the optimal height and cross-section of the chimney. This calculation can be carried out using 2 formulas. We will present the basic, but complex formula in this chapter, and we will present the basic, simple formula when performing a trial data calculation: 
- C is a constant coefficient equal to 0.034 for wood-burning stoves;
- the letter “a” is the value of atmospheric pressure. The value of natural pressure in the chimney is 4 Pa;
- The height of the chimney is indicated by the letter “h”.
- Т0 – average level of atmospheric temperatures;
- Ti is the amount of heating of the exhaust gases as they exit the pipe.
Example of calculating the cross-section of a chimney
We take as a basis:
- the potbelly stove runs on solid fuel;
- within 60 minutes, up to 10 kg of hardwood firewood burns in the stove;
- fuel moisture level – up to 25%.
Let's look at the basic formula again:
The calculation is carried out in several stages:
- We perform the action in brackets - 1+150/273. After calculations we get the number 1.55.
- We determine the cubic capacity of the exhaust gases - Vr = (10*10*1.55)/3600. After calculations, we obtain a volume equal to 0.043 m 3 /sec.
- The area of the chimney pipe is (4*0.043)/3.14*2. The calculation gives a value of 0.027 m2.
- Let's take it Square root from the area of the chimney and calculate its diameter. It is equal to 165 mm.
Now we determine the amount of thrust using a simple formula:
- Using the formula for calculating power, we calculate this value - 10 * 3300 * 1.16. this value is equal to 32.28 kW.
- We calculate the level of heat loss for each meter of pipe. 0.34*0.196=1.73 0.
- The level of gas heating at the exit from the pipe. 150-(1.73*3)=144.8 0.
- Atmospheric gas pressure in the chimney. 3*(1.2932-0.8452)=1.34 m/sec.
Important! Using the data from your furnace, you can perform the calculation yourself, but to be on the safe side, it is better to consult with specialists. The safety of your home and the economical operation of heating devices depend on the correctness of the calculation.
Swedish calculation method
The size of a chimney for a stove can be done using this method, but the main purpose of the Swedish method is to calculate the chimneys of fireplaces with an open firebox.
In this calculation method, the size of the combustion compartment and the volume of air in it are not used. To determine the correctness of the calculation, use the following graph: 
What is important here is the correspondence between the area of the combustion chamber (“F”) and the opening of the chimney (“f”). For example:
- firebox dimensions 770/350 mm. We calculate the area of the compartment - 7.7 * 3.5 = 26.95 cm 2;
- chimney size 260/130 mm, pipe area - 2.6*1.3=3.38 m2;
- We calculate the ratio. (338/2695)*100=12.5%.
- We look at the value 12.5 at the bottom of the table and see that the calculation of length and diameter was made correctly. For our stove it is necessary to build a chimney 5 m high.
Let's look at another example of calculation:
- the firebox is 800/500 mm, its area is 40 cm 2;
- chimney cross-section 200/200 mm, area 4 cm2;
- We calculate the ratio (400/4000)*100=10%.
- Using the table, we determine the length of the chimney. In our case, for a round sandwich pipe it should be 7 m.
What to do if the chimney cross-section is square?
Cylindrical chimneys, especially after the advent of sandwich pipes, are the most common types of devices. But when building a brick kiln, you have to lay out a square or rectangular shape.
In such chimneys, turbulence is formed, which prevents the normal passage of exhaust gases and reduces draft. But for wood stoves or fireplaces - rectangular pipes remain the most popular form. Such devices do not require an increased level of exhaust gas extraction.
Calculation of a chimney for a wood stove with a square or rectangular cross-section is made taking into account the ratio of the pipe size to the size of the blower hole on the stove. This proportion is 1/1.5, where 1 is internal section pipeline, and 1.5 are the dimensions of the blower or ash pan.
What should be the height of the chimney pipe for a stove?
Calculation of this parameter allows you to avoid the occurrence of backdraft and other possible troubles. This issue is regulated by the rules of SNiP and other documents. 
Why is this parameter needed?
In order to understand the importance of this factor, let's take a closer look at several physical laws and the consequences of incorrectly made chimneys. When heated gases pass through, the temperature decreases, but warm air or gases always rise upward.
At the outlet of the pipe, the temperature drops even more. Exhaust gases located in a pipeline with a reliable layer of thermal insulation have a high temperature and a column of heated smoke, rising upward, increases the draft in the firebox.
Let's analyze the situation - we reduce the internal cross-section of the pipe and increase the height of the pipe above the roof ridge. If you think that the volume of heated gas increases, the cooling time of the smoke increases and the draft increases, this statement is only half true. The traction will be excellent, even with a large surplus. Firewood will burn quickly and the cost of purchasing fuel will increase.
An excessive increase in the height of the chimney can cause an increase in aerodynamic turbulence and a decrease in the draft level. This is fraught with the occurrence of reverse draft and smoke escaping into living spaces.
SNiP requirements
The length of exhaust gas exhaust pipelines is regulated by the requirements of SNiP 2.04.05. the rules require compliance with several basic installation rules:
- The minimum distance from the grate in the firebox to the protective canopy on the roof is 5000 mm. Height above the level of the flat roof covering 500 mm;
- the height of the pipe above the roof slope or ridge must correspond to the recommended one. We will talk about this in a separate chapter;
- if on flat roof there are buildings, the pipe should be higher. In this case, with a large pipe height, it is secured with braces made of wire or cable;
- if the building is equipped with a ventilation system, their height should not exceed the exhaust gas outlet hood.
Self-calculation method
How to independently calculate the height of the smoke channel, for this you will need to perform a calculation using the formula: 
- “A” - climatic and weather conditions in a given region. For the north, this coefficient is 160. You can find the value in other areas on the Internet;
- “Mi” is the mass of gases passing through the chimney in a certain time. This value can be found in the documentation of your heating device;
- “F” is the time for ash and other waste to settle on the walls of the chimney. For wood stoves the coefficient is 25, for electric units - 1;
- “Spdki”, “Sfi” - level of concentration of substances in the exhaust gas;
- “V” — exhaust gas volume level;
- “T” is the temperature difference between the air coming from the atmosphere and the exhaust gases.
There is no point in giving a trial calculation - the coefficients and other values will not be suitable for your unit, and extracting square roots will require downloading an engineering calculator.
Table “Height of the chimney above the ridge”
The table of the height of the chimney above the roof structure will help you determine the size of the pipes without making complex calculations. First, we will analyze the selection of pipe length for flat roofs.
Conclusion
By performing the calculation or determining the size using the table, you will not only protect your home from fires, but also significantly save on fuel. The main thing is to carefully and responsibly carry out the installation and comfort and coziness in the house will be ensured.
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