What should be the height of the pipe relative to the roof ridge

Chimney functionality

It is from the height of the pipe and the material used for its device that depends:

• fuel combustion quality;
• the formation of good traction, which directly depends on the height of the pipe;
• how quickly the pipe walls warm up - rapid heating leads to the elimination of condensate, which does not have time to form with good traction.

The quality of the material also affects the traction. When installing brick chimneys, it is necessary to make the inner surface as smooth as possible in order to exclude the possibility of settling a large amount of soot and soot.

It is not recommended to use a clay solution to finish the pipe inside, since clay is a poor conductor of heat, which leads to the formation of condensate and a decrease in traction.

As you can see, everything is very closely interconnected in the arrangement of chimneys, but the main determinant of the good functionality of fireplace stoves or heating boilers is still the optimal height of the chimney.

The choice of the pipe section for the furnace

Experts do not recommend tapping ceramic bricks in addition to ensure that it falls into place. During the tapping process, an air space is formed, which affects the draft of the flue gas. If it is required to lay 4-6 rows of bricks from the inside of the pipe, then the brickwork of the chimney is wiped with a damp cloth, and all the seams are rubbed. The masonry seam is usually 0.5 cm in the horizontal direction, and 1 cm in the vertical direction.

The shape of a brick chimney for a metal stove or fireplace affects the level of hydraulic resistance in the pipe, so its cross section can be in the form of a rectangle or square. The best option is a round shape of the chimney, but laying it out of brick with your own hands is quite difficult.

The chimney should not have turns and slopes, since these types of elements lead to the creation of additional air resistance. If you can not do without a turn, it is easy to equip it at an angle of 60 °. Pipe laying involves the arrangement of a headboard made in 1 brick. The layout of the upper part is carried out on a cement-sand mortar.

The level of heat transfer from the stove or fireplace should depend on the choice of section. The cross section can be within 260x260 mm. For example, if the selected section is 130x130 mm, then the heat transfer is 3.5 kW, and with a section of 130x250 mm - more than 3.5 kW. You should not choose a very large pipe cross-section for a boiler, stove or fireplace, since this will lose the heating efficiency, which leads to a decrease in heat transfer.

Self-calculation technique

How high should the chimney be? This parameter is regulated by SNiP 2.04.05-91 (the original document can be found here).

According to this document:

• the minimum height of the smoke channel from the grate to the head is 5 m;
• the optimal height is 6 m.

Parameters affecting the height of the chimney

How to calculate the height of the chimney? Experts recommend using the following formula.

How to independently calculate the height of the smoke channel

Based on the presented formula, it is possible to determine the parameters that significantly affect the height of the chimney:

• meteorological conditions of the surrounding area (parameter A). For the northern regions, the value of the coefficient is assumed to be 160. For other regions, the value can be found in descriptive documents;
• the mass of the substance passing through the pipes per unit time (Mi). The data can be determined on the basis of the documentation supplied with the heating equipment;
• settling rate of particles resulting from combustion (F).For ash with wood heating, this coefficient is taken equal to 25, and when using an electric heater F=1;
• the concentration of various substances in the gas to be removed (Spdki and Cphi). The indicators are taken from the descriptive characteristics of the heating equipment;
• exhaust gas volume (V);
• the difference between the temperature of the incoming air and the air leaving the pipe (T).

It is quite difficult to calculate on your own, so it is recommended to seek help from specialists.

Optimum pipe height on the roof

The height of the chimney above the roof is also determined by SNiP 2.04.05 and the shape of the roof. This indicator is regulated as follows:

1. For a flat roof, the height of the chimney is determined as follows:
   • in the absence of parapets and other devices, the minimum height of the chimney above the roof is 120 cm;
   • in the presence of protective borders and other equipment, the length of the pipe must be increased. You can calculate the parameter by increasing the maximum length of the equipment by 1 m;
   • if there is a ventilation pipe on the roof, then the height of the chimney duct must be 50 cm higher than the height of the ventilation duct. In this case, it should be noted that the flue pipe must be located at least 5 m from the ventilation shaft.

Determining the height of the flue duct for a flat roof

1. What is the height of the chimney on a pitched roof? The parameter should be determined based on the location of the smoke outlet, namely, on its distance from the roof ridge, that is:
   • if the pipe from the heater comes out closer than 1.5 m from the roof ridge, then its minimum height should be 500 mm;
   • the height of the chimney from the ridge when the pipe is removed at a distance of 1.5 - 3 m should be equal to the maximum height of the roof;
   • if the chimney exits to the roof at a distance of more than 3 m from the ridge, then an angle of 10º should form between the horizontal line of the ridge and the end of the chimney.

Determining the length of the smoke channel for a pitched roof

The height of the chimney on the roof depends on its location and is determined by regulatory documents.

The height of the chimney above the ridge is also determined based on external factors such as nearby tall trees or buildings. In the presence of third-party interference, a so-called wind backwater zone is formed, in which it is impossible to equip traction sufficient for the correct operation of the heater. To improve traction, it is required to increase the height of the pipe by at least 50 cm to exit the wind zone.

How to calculate the length of the chimney when there are tall objects near the house

A similar situation develops when installing heating equipment in a utility room located in an annex to the main house.

Calculation of the height of the pipe when the heating device is located outside the main house

To improve the draft in the chimney, it is important that the head of the flue duct is located above the wind backwater zone. How to correctly calculate the height of the chimney, depending on the type of roof and the location of the channel, as well as when a wind backwater is formed, can be seen in the video

You can see the video on how to correctly calculate the height of the chimney depending on the type of roof and the location of the channel, as well as when a wind backwater is formed.

Determining the height of the smoke channel is necessary for the correct operation of the heating equipment. It is advisable to entrust the calculations to experienced specialists, since an incorrect determination of the parameter can lead to irreparable consequences and harm not only property, but also the health of people around.

The height of the chimney relative to the roof ridge SNiP

There is an opinion that the height of the pipe relative to the roof ridge is determined solely by the desire of the homeowner and the exterior of the house. However, it is not.In fact, the efficiency of heating equipment, the high-quality removal of combustion products, and the level of energy consumption depend on it.

Competent calculation of this parameter is based

• at the location of the pipe in relation to the ridge;
• the slope of the slopes;
• the presence of objects or trees near the house that are higher than it;
• the intensity of wind and snow loads characteristic of the area.

Advice
The calculation of the cross section of the chimney and its height is based on the basic requirements of SNiP, as well as the recommendations of manufacturers of heating appliances.

Here are the optimal values ​​of the desired value for some structures:

• Flat roof. Regardless of the section, the height of the pipe must be more than half a meter.
• Pitched roof. Let L= distance from the ridge bar. At

• L = 1.50 m, the height of the pipe cannot be 50 cm run or enclosing parapet more than 50 cm;
• 1.5
• L > 3 m, then the parameter is determined by an imaginary line constituting 10◦ with the horizon line.

Determining the optimal height of the chimney

Lowering the temperature of the smoke increases the mass of the products of combustion, thereby reducing thrust.

In addition to the height of the pipe, the efficiency of the heating devices is also influenced by the location of the chimney on the roof relative to the ridge and nearby buildings with high roofs, the priority direction of the winds in the area.

Design parameters for the location of the chimney on the roof

The location and calculation of the height of chimneys are regulated by SNiP 2.04.05-9, which states:

• the height of the chimney, counting from the grate to the top, should not be less than five meters. The optimum height of the chimney is 6 meters or slightly higher;
• if the chimney exits onto a flat roof without a high enclosing parapet, its height must be at least half a meter above the roof plane;

Chimney height on a flat roof

• if the chimney pipe is within 1.5 m from the roof ridge or high enclosing parapet, then its upper edge should be 0.5 m higher than the level of these structures;
• the chimney, located within 1.5-3.0 m from the ridge of the roof or parapet, must be flush with them;

The calculation of the height of the chimneys, provided that the structure is located further than 3 meters from the roof ridge or parapet, is as follows - the height of the upper edge of the pipe should be located so that the horizontal line drawn from the ridge and the line combining the top of the pipe and the ridge form angle equal to 10 degrees.

Chimney Height Calculation

In addition to calculating the height relative to the ridge or parapet, you need to pay attention to how the shape of the pipe and the size of its section affect the operation of heating devices. The rounded shape of the chimney is considered ideal, in which the exhaust of gases occurs evenly, without turbulence

An important condition for stable draft is the section of the chimney pipe, which is the same throughout.

If the structure is built of brick or other material, taking a rectangular shape, then the aspect ratio of the rectangular section must be maintained at 1:1.5. In this case, the corners of the internal section should take rounded shapes.

With a rectangular chimney, its cross-sectional area should not be less than 10 sq cm. A round chimney cannot be less than 15 cm in diameter, and in the case of a chimney - 18 cm.

As for the height of the chimney of the boiler room, it is usually very significant. With a height exceeding 6-8 meters, such a structure should be additionally reinforced with stretch marks, the ends of which are securely fixed at some distance from the building.

If you don’t know how to calculate the height of the chimney when building your house, then you should contact specialists or use free services on the Internet, where, according to your parameters, an online calculator will give the result in a matter of minutes.

It must be remembered that the height of the chimney above the roof must be calculated based on fire safety standards. It is unacceptable to place the chimney in the immediate vicinity of windows, doors, skylights, as flying sparks can cause a fire.

The minimum height of the chimney can be achieved by placing it close to the ridge. This option is better because the main trunk of the structure passes through the attic space, therefore it will be less subjected to cooling, as a result of which there is less risk of condensation forming inside and worsening its traction.

How to calculate the height of the ridge of a gable roof

The desired value depends on several factors, but, as a rule, the type of attic is considered decisive.

Recommended
If an attic device is supposed, then the calculated value is equal to the sum of the heights of the racks for the run and the ceiling of the room.

In the general case, the slope of the slope and the dimensions of the structure and, as a derivative, the type of material are taken into account. The calculations use data from a specially designed table, in which the width of the structure and the magnitude of the slope are related through the coefficient.

Let's say the width of the building is 8 m, and the slope is 40 °. The height of the ridge of a gable roof is calculated according to the following scheme: half the width is multiplied by a coefficient, the value of which is found from the table. Thus, the height or distance between the top of the roof ridge and the ceiling is 4 x 0.86 = 3.44.

Key points in design

The design of the chimney is developed without breaking away from the entire design of the building and the heating system. The place of the device is selected based on the layout of the building and interior, the design features of the building itself, the roof.

As a rule, a chimney is arranged in the kitchen, less often in the corridor or utility rooms, if the wall between the corridor or these rooms is common with the kitchen. This applies to the chimney for the furnace. But in the house there may also be chimneys for a heating boiler, a fireplace. As a result, several pipes will be displayed on the roof.

But you can not bring all the pipes to the roof. There is a technology for combining several pipes into one chimney. This must also be taken into account when designing chimneys and when designing the entire building. In this case, the volume of all exhaust gases from several sources of their formation should be taken into account, and the internal size of the chimney should be calculated accordingly.

When designing chimneys, one should take into account, in addition to the height of the pipe, the configuration, internal section, material of production, the type of heating device - a boiler, fireplace or stove, as well as the type of fuel - solid, gaseous or liquid. An incorrectly drawn up project will entail a decrease in the efficiency of the heating devices, hence the high fuel consumption and, accordingly, an increase in cash costs.

Influence of the height of the chimney on the efficiency of heating appliances

As mentioned above, the height of the chimney directly affects the quality of the heaters. From this we can conclude that the higher the pipe, the better will be the thrust and efficiency of the heating devices.

But not everything is as simple as it might seem at first glance. When constructing too high structures, the thrust will become less. Paradox? No, it's all about the aerodynamic resistance to which the combustion products are exposed in the chimney.

Smoke rises more slowly if the pipe is too high, as a result of which it cools more slowly, heating the walls.

How to DIY

The run is made of steel or wood. During the construction of private houses they mainly use the second option, since steel ones are quite heavy.

Recommended
Before installation, the beam is impregnated with a fire-retardant agent to ensure the durability of the structural element.

• The installation is carried out after completing the main stages of the roofing device.The basic principle of laying the elements of the ridge trim is laying the extreme fragments from the side of the gables, through which the mounting cord is pulled. The lace is aligned to the level and temporarily fixed to the opposite gables. It will serve as a guide for the rest of the fragments.
• Work is recommended to be done by two people. After installing and fixing the first structural element, proceed to the next one. Fragments are laid with a spade of about 20 cm, which allows for better waterproofing of the structure. In the same way, all the elements are laid and fixed along the slope.

Attention!
Particular attention should be paid to the fastening of the outer elements, since they are under the influence of maximum wind loads.

• However, just one fit, even if the shelf is more than 20 cm wide, is not enough to provide sufficient waterproofing. In any case, gaps will remain through which drops of rain or snow blown by the wind can get under the roof. You can put a layer of glass wool in the groove, but try not to compact it too much, as this may interfere with ventilation.
• There is another way: instead of glass wool, use a self-adhesive foam rubber tape (filler), which is laid along the edge of the shelf from the bottom side. But this material is quite expensive, and the result obtained is similar to the option using glass wool.
• A ventilation compartment must be provided without fail. Otherwise, the accumulation of condensate cannot be avoided, even if the roof has been reliably protected from moisture.

On a note
If, due to the peculiarities of the roof structure, it is not possible to equip it or at least provide the necessary clearance, then to combat attic dampness, windows are installed in the end parts.

How to fix the ridge on the roof: from corrugated board, on slate

The mounting method depends entirely on the material of the protective strip. Curly elements are often made from the same.

A mandatory procedure is the waterproofing of wooden roof elements. Prior to the installation of finishing elements, the run is covered with roofing tape.

Roofing from corrugated board. Let us dwell in more detail on how to install a ridge on a corrugated roof.

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• Strips of sealant or special ventilation tapes are attached to the edge of the profiled sheet, which correspond to the pattern of the sheets.
• Fastening is carried out in increments of 20–30 cm based on the parameters of the profiled flooring pattern. The overlapped elements are fixed to the already installed bars, screwed with self-tapping screws through the upper corrugation.

Attention!
Note that self-tapping screws must be equipped with rubber or neoprene seals.

To get the most durable and high-quality connection, it is recommended not to screw in all the hardware at once. It is advisable to make fragments for two to four hardware each. The rest are tightened only after checking the cord and level. Agree that every extra hole in the roof poses a potential threat to its reliability.

Ventilation device

To create ventilation, you must perform the following operations.

• After installing the rafter system, a waterproofing film is fixed across them. The connecting seams are glued with mounting tape. In this case, an overlap of 150 mm is required;
• A crate is installed along the rafters. The movement of air flows occurs precisely due to the gap formed by the crate. If the waterproofing does not allow moisture to seep into the heat-insulating layer and the wood of the supporting structure, then the gap provided by the crate makes it possible for any moisture to dry out fairly quickly.
• An additional ventilation hole is created in the ridge part. Excess steam and condensate are removed through it.
• At the bottom of the eaves, it is necessary to provide gaps through which air from the outside will flow under the roof.

How to mount a ridge for a roof made of metal, you can see on the video.

https://youtube.com/watch?v=LDszZ7EqCyY%3F

2019 stylekrov.ru

Varieties of pipes for stoves and fireplaces

There are the following types of chimneys:

1. Brick-mounted pipes are massive objects resting on the stove masonry; they need to be laid out with a thickness of at least half a brick.
2. Root pipes are free-standing structures in the form of risers, they should be made from an asbestos-cement pipe with a diameter of 15-20 cm.
3. Prefabricated pipes are separate blocks made of heat-resistant concrete.
4. Wall pipes are structures mounted in a main load-bearing wall, which saves space in the room.

A chimney built into a load-bearing wall should be located in the house itself. Experts do not recommend installing chimneys in external walls, since the air from the street will cause the flue gas to cool and also reduce draft. As a result, this will lead to the formation of condensate inside the channel.

Obtaining high efficiency from a furnace having this type of tube is not possible. If another way of arranging the wall chimney is not provided, appropriate types of work are carried out to equip the pilaster with a ledge that goes inside the room. Installation is carried out with the required distances from the chimney to the outer wall:

• 2.5 bricks (from 20 to 30 - 650 mm);
• 2.0 bricks (from 20 and above - 510 mm);
• 1.5 bricks (from 20 and below - 380 mm).

The location of the chimney is determined strictly vertically without indentation inside. If there is a withdrawal in the structure, its dimensions should not be more than 1 m. A brick pipe often has a section inside that is at least 140x140 mm. Normal chimney draft is achieved by a chimney height of at least 5 m. If it is less than 5 m, draft is provided using a diffuser deflector.

Having equipped your house with stove and fireplace heating, you should install 2 chimneys. Different draft of one of the hearths can lead to smoke. In a wooden house, in places where there is an adjacent brick chimney, a thickening of 1-1.5 bricks is provided. A flammable structure near the chimney should be closed from it with asbestos-cement or metal sheets.

The pipe, which excludes the drift of the chimney with snow, should be located 0.5 m above the roof. To protect the end of the pipe head, a metal cap or a steel sheet edging is used. At the exit section of the furnace chimney, a passage through the roof is mounted, which makes it possible to exclude the spread of moisture in the attic. The passage unit can be equipped from a steel sheet independently.

What nuances should be considered when planning a chimney

To develop an ideal project, it is impossible to do with calculations and constructions alone. The chimney intersects with the internal elements of the room, which means that it will certainly affect the layout. Even if you really want to mount it as close to the ridge as possible, you may encounter a number of difficulties in achieving this goal. And, as a rule, as a result, the chimney has to be placed at a great distance.

What should be the height of the chimney above the roof will depend on such nuances:

• room interior;
• type of chimney;
• number of floors;
• ease of installation of the smoker;
• accessibility for preventive maintenance;
• type of material used during the construction of the walls and rafter system;
• the number of connected elements to one chimney.

It should be noted that according to the rules for arranging heating systems in private houses, it is possible to connect only one unit to one chimney. And only in special cases is it allowed to carry out the removal of exhaust gases through one pipe from two furnaces. At the same time, for the correct functioning of the system, a cut must be installed inside.

Furnaces in two- and three-story houses are installed one on top of the other, and their chimneys are arranged in such a way that they can exit through one shaft.

Based on the design, chimneys are of the following varieties:

• Wall. They are considered the most economical option, they are easy to install and easy to maintain. Such chimneys are mounted in brick and stone structures, in those places where it is possible to lay a channel in a bearing wall.
• Indigenous. Such chimneys are erected separately from the furnace. This design is more expensive, but in some cases it is possible to install only it. They are erected in the absence of technical capabilities for arranging a wall channel. Root chimneys are built, as a rule, if it is necessary to install chimneys in stacks, from a bar or log.
• Attached. Such a chimney is installed directly on the reinforced concrete floor of the stove when arranging small buildings that need a competent distribution of free space.

Most designers prefer the use of risers, that is, smoke channels that are built during the construction of walls - they make it possible to save a lot on building materials. However, if the box does not have a main wall, it is not possible to lay risers. Nevertheless, if you still decide to install smoke channels, then it is better if they are located as close as possible to the ridge run.

The construction of a wall chimney is carried out using a buoy template, which is lined with bricks on all sides. It is a special box made of wood, the diameter of which is equal to the diameter of the chimney. Having reached the top of the template, it is moved higher, after which it is laid over again. Actions continue until the construction of the bearing wall is completed.

Often, brick pipes are placed on the inside of the main walls. Thus, more efficient heating of the house is achieved, it is possible to reduce heating costs. Sometimes risers are installed in external walls, but this approach is more costly and will require more effort during subsequent operation.