home ceilings

Which chimney is better. Do-it-yourself brick chimney in a private house. Tools and materials

"Dymar" is a part of the furnace, on which both the efficiency and overall efficiency of the furnace, as well as the safety of its use, largely depend.

Choosing a stove is a complex process that requires a certain level of knowledge. In this article, we will tell you how to properly approach this issue and make the right decision.

Purpose and design features

The chimney performs the function of removing the products of combustion of firewood (or any other fuel) during the burning of the fireplace. In addition to smoke, ash, soot and soot come out through the hole.

A properly made chimney provides maximum efficient work furnace and its safety.

The issue of arranging for a fireplace should be approached as seriously as possible, because the slightest flaws in its mechanism can significantly reduce the efficiency of the furnace and accelerate its wear.

This is poor smoke removal, and as a result, smoke in the room in which the stove is located, excessive soot settling on the walls of the smoker (and therefore creating a blockage), and similar troubles.

When in question the fact that without a normal pipe the fireplace will not realize its potential to the maximum, we are talking about the fact that it is the smoker that provides draft to the fireplace.

This happens for the following reason: the temperature of the combustion products leaving the chimney is very high (sometimes reaching one hundred degrees), which creates natural draft due to the pressure difference between hot and cold air.

The traction force directly depends on the height and diameter of the furnace, as well as on the thickness of its walls: it should not be too thick or too thin.

It is necessary that the smoke does not have time to cool down during the journey through the chimney - in this case, the draft will weaken, and vice versa.

Types and differences

Structurally, there is a division into three main categories. Let's consider each separately.

Indigenous

Not the most popular option, as it takes up a lot of free space in the room. The root smoker is a brick device that has its own foundation and is installed next to the stove.

The application will be appropriate in buildings where several fireplaces are located in one place.

In this case, their smoke channels can be led to one smoker, or in houses built from wood, where it is impossible to make a smoke channel inside a load-bearing wall.

wall

These are chimneys that are built into bearing wall room near which the fireplace is located.

Their use is justified in brick houses, since they have a significant advantage (such mechanisms do not take up the free space of the building).

However, their arrangement is a rather difficult process, requiring design and implementation at the stage of building a house.

Shell-mounted

This is perhaps the most popular, due to its simplicity, option. A mounted chimney is, in fact, a continuation of the chimney of the fireplace itself.

For such chimneys, it is required to use stove insulation, but they are extremely easy to implement and do not require serious material costs.

Apart from design features chimneys, smokers can now be carried out with different materials, each of which has its own advantages and disadvantages.

The main types of materials used in the manufacture of smokers (chimneys):

from ferrous metal: along with the cheapest materials, which, due to its cheapness, is widespread, although they do not differ in particular durability and environmental friendliness.
brick - this is perhaps one of the most popular types of chimneys. It is reliable, durable, but rather difficult to implement, and should be carried out only by a competent stove-maker: since a lot of factors affect whether a brick chimney will effectively perform its functions - from the degree of hardening of the brick to the perfect accuracy of construction.
made of stainless steel: quite simple, but at the same time reliable and effective mechanisms. Stainless steel perfectly removes smoke and soot, as its surface is as smooth as possible. It is heat resistant and not afraid of water. by the most the best option is galvanized.
Ceramic: getting more and more popular in recent times. This is already a complex modular system, which is manufactured in industrial conditions, and sold in stores in a complete kit, ready for installation.

Nuances of choice

The type of chimney or chimneys to be used is determined in each individual case depending on the structural characteristics of the building, the type and financial capabilities of the owner.

A pipe for a fireplace must be easy to install and meet all safety standards, because it is through the wrong design of the chimney or installation errors that most fires happen.

First of all, you need to determine the diameter.

There is one simple rule that must be strictly adhered to: the diameter should not be less than the diameter of the chimney channel of the fireplace itself, since the height directly affects the traction force, it is necessary to approach its calculation with great responsibility.

The optimal distance is considered to be at least 50 centimeters from the top to the place where it comes from the roof, if it is located on a flat roof.

If the roof is with a strong slope, and the smoker is brought out at a distance of less than 1.5 meters from the parapet or ridge, then it should rise 50 cm above its level.

If the chimney is in the range of 1.5-3 meters from the ridge to the parapet, its mouth should be at the level of the top point of the roof. This is necessary so that the roof does not interfere with the free removal of smoke by air currents.

At the same time, the total height of the structure, from the exit to its upper point, must be at least 5 meters.

Installation nuances

We will talk about installing a tube with a spark arrester, since this option is most common in ordinary homes.

Installing a stainless steel appliance for a home (a metal tube for a stove, as already mentioned, is very popular), is a fairly simple process that can be done by anyone with their own hands.

Unlike indigenous, and even more so wall pipes, they must be installed by specialists.

When installing a packed pipe, the following principles should be followed:

The built-in pipe for the stove for the house must be at least a two-section structure, because the lower part of the metal structure, due to the heat from the furnace, can “burn out”, and over time it will need to be replaced.
It is very important to pay attention to such a moment as the insulation of the tube in the ceiling. Where the unit passes through the roof, a layer of refractory insulation must be installed to minimize the risk of fire due to hot surfaces touching other surfaces. For this reason, the passage of the stove through the ceiling is required to be insulated without fail.

Thermal insulation for devices or, in other words, thermal insulation of a chimney made of stainless steel or metal is a matter of high relevance.

Due to the thin wall, these products may not provide the necessary thermal insulation properties, which will lead to moisture condensation on its wall, and further deterioration of traction and destruction of the tube itself.

The best option for warming a house is Izovol basalt wool, which wraps pipes for furnaces. This is a non-combustible material that has sufficient flexibility and frost resistance, and at the same time it is environmentally friendly.

Furnace pipes are wrapped around the perimeter basalt wool, which are reinforced with wire (where the spark arrester is located).

This operation is repeated until the entire structure is insulated, preferably up to the upper section on which the spark arrester is located.

Installation goes through the following steps:

The first knee is put on the air duct.
The second knee is put on the first.
A refractory strut is made. The correct cutting on the ceiling is made of two layers: 1 - stainless steel sheet, 2 - galvanized box, and all this is fixed with a clamp.
The third knee is first introduced into the attic, through a hole in the ceiling, and then connected to the second section (where the spark arrestor is).
The deflector for the smoker and the spark arrester is put on its upper part. This part of the design serves to enhance traction. Basically, at industrial production deflector on it is connected into one design.
The pipe on the roof can also end in a head (although sometimes there is a spark arrester) that will protect it from rain.

Installation nuances (video)

Approximate rates

Prices for chimneys (as well as for insulation for them) depend on their size and material. In addition, of course, there is a spread in the price level from manufacturer to manufacturer, but we can talk about the following amounts:

the price of a pipe heater for a stove with a diameter of 200 mm is about $ 18 per 1 m;
the price for a heater of stainless steel devices with one contour, 0.5 mm thick and 200 mm in diameter - from 10 to 13 dollars per meter;
the price of a spark arrester is from $10.

You can buy a metal stove pipe at any major building materials store.

The price of brick pipes depends on the cost building material and oven work. So, a brick pipe for metal furnace will cost you about 25-30 dollars per linear meter.

The chimney at first glance seems to be a simple design. In fact, this is a brick pillar with a channel inside for the output of combustion products. In practice, its dimensions and design determine whether the furnace will function at all, since it is the chimney that is responsible for the draft.

Material

The size of the chimney, no doubt, depends on the material from which it is made, and the latter is selected in accordance with the heater and the combustion temperature of the fuel.

A stove in a private house belongs to the category of solid fuel boilers - coal, firewood, which means that the chimney material must be ready for the action of flue gases at a temperature of 500–800 C and a short-term increase in heating to 1000 C. Only heat-resistant materials are suitable for this.

Brick - refractory, of course. Withstands a constant temperature up to 900 C, heats up for a long time and gives off heat for a long time, which is an advantage for a chimney laid inside a building. Due to the same property, it is not suitable for low-efficiency and gas boilers.
Stainless heat-resistant steel - you need to use a product from this category, despite the higher cost. Firstly, such a brand really withstands heating up to 800 C, and secondly, it is resistant to acids and condensate.
Glass - made of refractory glass, it has excellent performance characteristics, but it is difficult to install and has a decent cost. This option is used for fireplaces.
Ceramic - designed to operate at temperatures up to 1200 C, resistant to condensate, chemically inert. They would be the most popular option for a chimney in a private house, if not for the higher cost.

The choice of material is also influenced by the nature of the fuel. Brown coal, stone, wood of different breeds have different calorific value. In addition, it emits different amounts of soot, soot and acid anhydrides.

Section shape

The diameter of the chimney is a somewhat arbitrary value, since during the construction brick oven, the default chimney is also satisfied with brick. However, it is now more common to place a metal or ceramic pipe inside it to improve its performance.

However, such a decision should not be in a hurry, and here's why.

Rectangular section provokes the formation of turbulence. The smoke rises in a spiral, part of it, once in the corners, slows down and forms a separate swirl. This worsens the draft, so for a boiler that needs good draft, this option is not rational.
However, for wood-burning stoves and fireplaces in the home, the picture is different. Very good draft is not needed here, and even vice versa: during this additional time, the smoke gives off more heat and the room warms up better and faster. Thus, it is even possible to compensate for the insufficient number of smoke circulations.

For furnaces, a chimney with a square or rectangular section is considered optimal. And to improve it performance characteristics, various types of lining are used.

House chimney diameter

What diameter the chimney should be depends on the shape of the section and the power of the furnace. If finished industrial products are used, then, as a rule, special tables are attached to the instructions, which indicate the required cross-sectional area depending on the boiler power and its dimensions. If there is none, use general recommendations. When installing a wood stove, where the strongest draft is not necessary, the calculations may be approximate.

The inner diameter of the chimney determines the area of the firebox. The length and width of the section must be proportional to the length and width of the firebox in the ratio 1:1.5. This also applies to the shape of the section, respectively.

The cross-sectional area cannot be less than the blower area - this is required condition.
The power of the furnace, other things being equal, also affects the diameter. If the heat transfer of the device is less than 300 kcal / h, the cross-sectional dimensions must be at least 140 * 140 mm.
What diameter of the chimney of a private house is needed also depends on the design of the heating chamber. If it is open - fireplaces and stoves with open fireplaces, then it is equipped mainly with round chimneys - good draft is extremely important here. In this case, the diameter is defined differently: as 1: 10 in relation to the area of the furnace. In the photo - the device of the chimney.

It must be borne in mind that the inner and outer diameters of the stove chimney are different values. For a metal or ceramic chimney, both parameters are constant. A brick pipe is somewhat more complicated: when passing through the ceiling, it expands, but at the same time its internal dimensions must remain unchanged.

Perhaps everyone knows what chimneys are and what they are for. Those who were more deeply interested in the arrangement of stoves and fireplaces understand how important right choice smoke exhaust systems in the house or bath. This article is devoted to a description of what types of chimneys are their features, advantages and disadvantages.

This is one of the oldest types of chimneys, which is still very popular. They lay a brick chimney from a solid ceramic brick. The smoke exhaust channel is located in the brickwork.

The advantages of brick chimneys include:

resistance to mechanical stress;
high heat capacity of the structure, allowing the heated chimney to give off heat for a long time;
absolute fire safety subject to compliance with safety requirements.

Note: The disadvantages of brick chimneys are worthy of detailed coverage. Thanks to this, it will be possible to better appreciate the advantages that other types of chimneys have.

Disadvantages of brick chimneys

The rectangular section of the chimney is not a very good solution in terms of draft. In the corners, the flow rate of the flue gases is lower, which reduces the efficiency of removing combustion products from the furnaces.
Irregularities of the inner surface (protrusions and recesses) reduce the rate of passage of gases. Also, soot and condensate easily settle on such a surface. combustion products solid fuel or natural gas contain large amounts of sulfur oxides. An odorant is specially added to the gas, providing that very recognizable pungent smell. A feature of the odorant is the high content of sulfur. Sulfur oxides deposited on the walls of the chimney react with water (condensate), forming sulfurous (weak) and sulfuric (very caustic) acid. These acids are the cause of the destruction of bricks and mortar, reducing the strength of the structure.
The large mass of the brick chimney makes it necessary to build a separate foundation for it. Moreover, it is advisable to make the foundation for the stove and chimney before the construction of the building begins.
Complex and time-consuming installation of brick chimneys, which is incomparable with any other type. The work requires a highly skilled mason and takes several days.

Single-circuit modular steel chimneys

It is assembled from several elements. Most of the elements are a piece of steel pipe. However, the design also includes more complex elements - tees, equipped with glasses for collecting condensate.

The material for the chimney elements is acid-resistant heat-resistant stainless steel (stainless steel) with a wall thickness of 0.6-1 mm. Pipes manufactured according to these requirements have a long service life. In practice, they apply different types stainless steel and even galvanized steel. Galvanizing is the worst solution. The protective layer of zinc quickly burns out under the influence of temperature and the unprotected walls of the channel begin to collapse under the influence of water and acids.

Advantages of single-circuit steel chimneys:

smooth inner surface that prevents the deposition of soot and condensate;
round section, providing good traction and uniform gas flow rate;
light weight;
simplicity and low labor intensity of installation;
sufficiently high resistance to corrosion;
maintainability.

Disadvantages of single-circuit steel chimneys:

high thermal conductivity leads to rapid cooling of gases and the formation a large number condensate. Pipes require large indents at the points where the chimney passes through wooden elements buildings (ceiling, walls, roof).
short service life of the chimney - no more than 15 years.

Steel sandwich chimneys

Double-circuit sandwich chimneys - products from two steel pipes different diameters, inserted one into the other. The space between the pipes is filled with non-combustible insulation. Thanks to the insulation, sandwich pipes have low thermal conductivity, which provides additional benefits:

slow cooling of flue gases and high speed of their passage through the channel;
minimal formation of condensate;
the possibility of outdoor installation without output through the roof;
simplified requirements for installation inside the building and output through the roof.

The disadvantage of this type of chimney is one - the price. They are noticeably more expensive than other types of steel chimneys.

Steel corrugated

This type of chimney is made of a flexible pipe made of steel tape. Such flexible chimneys are used for lining brick smoke channels curved shape. These types of chimneys are easy to install and maintain, but their service life is very limited.

Ceramic

This type of chimney appeared in Russia quite recently, but quickly became popular, despite the high price. The smooth surface of the ceramic chimney does not need frequent cleaning. Each element of the ceramic chimney includes:

chimney made of special refractory ceramics;
a heat-insulating layer of non-combustible material that ensures safe passage through walls and roofs;
protective cover made of lightweight cellular concrete.

This type of chimney has collected all the advantages:

smooth inner surface;
round section and smooth, good traction;
excellent thermal insulation and sealing;
heat and fire resistance;
ease of installation;
durability.

The disadvantages of ceramic chimneys include only their high cost. They can be used to remove smoke from any stoves, fireplaces, boilers and columns.

Asbestos-cement

Asbestos-cement pipes are used in the construction of chimneys for heating devices, the flue gases of which have temperatures not exceeding 300 degrees. They are not suitable for conventional ovens. These limitations are caused by the unsatisfactory heat resistance of chrysotile cement.

Asbestos-cement chimney pipes

Advantages of asbestos cement chimneys:

light weight (if we take brick chimneys in comparison);
round section;
simple quick installation;
very low price.

Price is the deciding factor here. This is the material that can be taken, as they say, "by the bottle."

Disadvantages of asbestos cement chimneys:

low strength;
poor heat resistance;
lack of thermal insulation;
the complexity of the device bends;
unreliable connection with rubber couplings;
porous wall structure;
frequent cleaning of chimneys.

The last point deserves special attention - the ignition of soot in asbestos-cement chimneys is a serious problem. For safety reasons, regular cleaning of such chimneys is necessary. Therefore, the use of this type of chimney has significant limitations.

Polymer

Flexible chimneys from polymer materials are used for lining brick or concrete smoke channels. The polymer does not have high heat resistance, so this solution is used only for the removal of not very hot flue gases. These requirements are met geysers and boilers with high efficiency. They cannot be used as a chimney for a stove.

Advantages of polymer chimneys:

ease of installation;
light weight and flexibility;
low price.;
long service life.

Disadvantages of polymer chimneys:

poor resistance to high temperatures;
lack of thermal insulation;
low strength.

The chimney is a necessary part of the heating system of a private house. It ensures the proper functioning of the stove or boiler, organizes the removal of harmful combustion products outside the housing.

We will try to figure out how to equip the chimney with our own hands so that the heating communications are safe for both people and the house.

The requirements for the installation of heating devices are set out in normative documentation.

The installation of devices is regulated by the provisions SNiP 2.04.05–91 and DBN V.2.5-20-2001. Also, before drawing up a project, it is advisable to study materials on heating systems ( SNiP 41-01-2003), about heat generation devices ( NPB 252–98), on the technical conditions for the operation of thermal devices ( GOST 9817–95), on the rules and regulations for the operation of smoke channels (VDPO).

The design of the chimney and installation features must fully comply with the requirements specified in the SNiP, otherwise you will not receive a certificate of inspection of the structure, which is issued after commissioning

Part of the requirements is addressed specifically to the device of chimneys. The design of the structure can be anything, but the material of manufacture must be non-combustible.

The materials used for the construction of chimneys can be:

steel;
ceramics;
brick.

Without exception, all structures are prefabricated, and the installation itself is fragmentary, since the chimney passes through several rooms (for example, a room and an attic).

In order for the structure to meet fire safety requirements, it is necessary to correctly calculate its parameters, as well as select all the component parts by size. When installing factory equipment, it is necessary to follow all the recommendations set out in the instructions, including the assembly procedure and methods for mounting parts.

Image gallery

Transitions through floors and roofs require the use of fire-retardant thermal insulation materials, such as mineral wool, and the installation of protective blocks, which can be called a "sandwich in a sandwich"

The construction of a chimney for a gas boiler, stove or fireplace is a responsible occupation that requires special permission, project planning and professional skills. If you are not confident in your abilities, entrust the installation of the pipe to specialists who will perform the work in accordance with all norms and requirements.

If you have already had to build a chimney yourself or you are an expert in this matter, please share your experience and knowledge with our readers. Tell us about the nuances of building a chimney in the block below.

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A do-it-yourself chimney for a stove can be erected if there is a layout of its masonry at hand, and House master possesses at least minimal skills in the work of a bricklayer. The construction of this department requires no less serious approach than, since the efficiency of heating, the safety of those living in the house, and the overall life of the entire heating structure will depend on the quality of its masonry.

When working on a chimney, it must be remembered that its internal surfaces must be as neat and even as the external ones, since this factor directly affects the creation of good traction.

Varieties of brick chimneys

Chimney pipes are divided into types depending on the location of their installation relative to the furnace itself. So, they are root, mounted and wall.

The most common design of a brick chimney is a wall-mounted one. It is installed directly on top of the heater and is its continuation. Such chimneys are often installed during the construction of a heating or bath stove.

The second most popular is the root chimney. This type of pipe is distinguished by the fact that it is installed next to the furnace or is included in its design and is placed on one of its sides.

Root pipes can be installed for both brick and cast iron stoves. In addition, one root structure is often used for several heaters. For example, in a two or three-story house, one chimney is passed through all floors and furnaces are connected to it. If it is planned to use the pipe in this way, then in this case, an accurate calculation of its parameters must be made, otherwise there will be no normal draft, which means that the efficiency of the furnaces will also decrease, and the risk of combustion products entering the premises will increase.

The wall pipe is built into the main internal or external walls. But, in the latter case, the walls of the chimney will have to be very well insulated, since due to the large difference in external and internal temperatures, condensate will actively collect inside the duct, which will significantly impair the operation of the furnace, reducing draft and contributing to the rapid growth of the chimney with soot.

It should be noted that although this structure is distinguished by a separate type, it can be both root and mounted.

Construction of a brick chimney

The chimney has several sections. To understand its fundamental design, we can take the structure of a packed pipe as an example, since it is most often chosen by development engineers when drawing up furnace ordering schemes.

So, the design of the extension pipe with its passage through the attic floor and truss system, includes the following departments and elements:

1 - Metal cap or umbrella. It can have a variety of forms, but its function is always to protect the interior of the chimney from the penetration of precipitation. different kind as well as dust and dirt.

2 - The head of the pipe consists of bricks protruding outward, which will protect the neck of the structure from raindrops that will flow down the protective cap. The metal umbrella is fixed, including on the protruding parts of the head.

3 - The neck of the pipe.

4 - Cemented or otherwise waterproofed inclined surface of the otter, designed to drain water that has fallen on the neck of the pipe.

5 - Otter. This part of the structure has thicker walls than the pipe neck. The otter should be located at the point where the chimney passes through the rafter system and the roof. The thick walls of the otter will protect the combustible materials of the crate under the roof from overheating.

6 - Roofing material.

7 - Lathing of the truss system.

8 - Rafter.

9 - Pipe riser. This department is located in the attic of the house.

10 - Fluff. This part of the chimney starts under the ceiling inside the house, passes through the attic floor and ends in the attic, just above or flush with the floor beams. The fluff, like the otter, has thicker walls than the neck and riser of the pipe. The increased thickness also protects the wooden beams and other combustible materials of the attic or floor from overheating.

It should be noted that in some cases, instead of fluffing in its place, a metal box is mounted around the pipe, filled with non-combustible materials, such as sand, vermiculite or expanded clay. The functions of this layer, having a thickness of 100 ÷ 150 mm, are also the protection of combustible floor materials from overheating.

11 - Floor beams.

12 - Insulation, which is most often made from asbestos, is in any case necessary to create fire safety, since the walls of the chimney will come into contact with the wood of the floor beams and other materials that make up the floor and ceiling.

13 - Smoke damper, located in the room, in the upper part of the pipe, which allows you to adjust the intensity of the discharged streams of heated air and combustion products.

14 - The neck of the pipe, which begins at the top of the furnace - the ceiling.

Calculations of the parameters of the chimney pipe

The principle of operation of the chimney system is the movement of air masses from the combustion chamber to the exit to the street, that is, from the lower point to the upper one. This process occurs through the creation of traction, which occurs due to temperature and pressure changes. It is thanks to all these factors that the normal functioning of the chimney system is carried out.

To create optimal aerodynamic processes, the size of the pipe channel must correspond to the power of the furnace, which, in turn, largely depends on the size of the furnace. The surfaces of the internal chimney space must have smooth walls, along which the air flows will slide freely without turbulence, and due to this, no reverse draft will be created. That is why quite often a tab from a round ceramic pipe is built into a brick square chimney, which has an absolutely smooth surface and does not have internal corners.

Section size

In connection with the factors mentioned, it is necessary to carefully calculate the internal size of the chimney, while taking into account its length, since the larger this parameter, the higher the draft in the pipe.

Of great importance for the creation of normal traction and the high-quality functioning of the heating device is the correspondence of the parameters of the chimney passage and power, as well as the size and number of channels provided for by the design and passing inside the furnace.

If the parameters of the internal dimensions of the chimney in the cross section exceed the calculated value, this will lead to a rapid cooling of the heated air in it and the formation of condensate, and hence a decrease in thrust. In this case, the necessary balance will be violated, and the streams cooling in the upper part of the pipe may return down, creating smoke in the room.

The size of the chimney opening is calculated as follows:

The size of the chimney of an open hearth fireplace corresponds approximately to the proportions of 1:10 (chimney section (f) / firebox window area (F)). This formula is generally valid for both a square or rectangular, and a cylindrical type of pipe, but not directly, but taking into account the cross-sectional shape of the channel and the total height of the chimney.
The size of the chimney of a furnace with a closed combustion chamber has a proportion of 1:1.5. In the case when the heat transfer of the heating structure is less than 300 kcal / h, then the cross section usually has a size of 130 × 130 mm or half a brick (at least). When making calculations, it must be taken into account that the cross-sectional size of the chimney should not be less than the inlet of the blower.

When calculating the fireplace chimney, you can use the following table.

Pipe height H, m		5	6	7	8	9	10	11
		f/F ratio in %
Pipe section	Round	11.2	10.5	10	9.5	9.1	8.7	8.9
	square	12.4	11.6	11	10.5	10.1	9.7	9.4
	Rectangular	13.2	12.3	11.7	11.2	10.6	10.2	9.8

Pay attention to the direct dependence of the chimney cross-section not only on the parameters of the furnace, but also on the height of the pipe. Probably, sometimes in the calculations it will be more expedient to build on this parameter. For example, a pipe 11 meters high on a one-story country house will look absolutely ridiculous.

The same dependence, but more accurately represented in the form of a graph.

Suppose you need to calculate the cross section of the chimney for a fireplace with a firebox, the window dimensions of which are 500×700 mm, that is, the total area - 0.35 m². It is assumed that a pipe with a total height of 7 meters.

Let's look at the graphic scheme:

- for a circular section of the chimney, the optimal ratio f/F=9.9%;

- for square - 11,1% ;

- for rectangular - 11,7% .

It is easy to calculate the optimal cross-sectional area of the chimney channel:

- a circle: 0.35×0.099 = 0.0346 m²;

- square: 0.35 × 0.11 = 0.0385 m²;

- rectangle: 0.35 × 0.117 = 0.041 m².

Now, using the simplest geometric formulas, it is easy to bring areas to linear dimensions:

- diameter round pipe: d = 2×√S/π = 2×√0.0346/3.14 ≈ 0.209 m = 210 mm.

- side of the square tube: a = √S = √0.0385 ≈ 0.196 m = 196 mm.

- a rectangle can have various options- For example 0.130 × 0.315 m or 130×315mm.

The calculation will be much easier if you use the calculator below, which already contains all the mentioned dependencies.