Asbestos chimney pipe - can it be used, installation and insulation

Every person who decides to build a bathhouse faces a difficult moment in choosing the material for the construction of the chimney. I want to make a smoke exhaust system quickly and inexpensively.

Ceramics are good, but expensive, brick is also great, but difficult. You can use metal, but you will need a welding machine to make the chimney.

Sandwich pipe is also not the cheapest material, and not all stores sell it, especially if the developer lives in a village. We have heard about stainless steel, and assembling a chimney from it is a simple matter, but for some reason we never get around to it.

And here some “specialists” come to the rescue, who unanimously suggest using an asbestos pipe as a chimney.

There are a lot of arguments in favor of its use. The most important one: “Look, I’ve had an asbestos chimney for 50 years and will stand for the same amount of time, and nothing has happened to it.”

The second argument is already on its way: “The chimney is installed simply, quickly, and tomorrow you will be testing the steam room,” and the deadlines are running out.

And when you first thought about it, someone will definitely say: “Yes, I have a lot of them, let’s go, I’ll give it to you for free.” After this, 90% of developers agree with the proposal, since the last argument almost always wins.

Let's figure out whether an asbestos chimney is so good.

Features of using asbestos cement products

According to the provisions of fire safety rules and SNiP, it is possible to construct chimneys from asbestos-cement pipes only in cases where the temperature to which the product is exposed does not exceed 300°C.
This is possible if:

The product is used as the upper part of the smoke channel, into which greatly cooled gases enter.
Asbestos pipe is used in low-power gas heating devices.

Limitations on the operating temperature are primarily due to the fact that when heated above the specified value, products made from this material burst. Consequently, its use in the initial sections of the chimney, where the temperature parameters are the highest, is strictly prohibited.

Such pipes cannot be installed in smoke shafts to remove solid fuel combustion residues from boilers.

In addition to cracking due to too high a temperature, another feature of the product is significant porosity and, as a result, accelerated absorption of accumulating condensate, leading to the destruction of the flue at the “dew point” - the base of the outer part of the pipe near the sheathing of the rafters and roof. A violation of the integrity of the surface can lead to a fire in the wooden parts of the roof frame in the area of the pipe.

User reviews and questions

I am considering installing a chimney from a solid fuel boiler using an asbestos-cement pipe with a diameter of 150 mm. The stove maker recommends making a chimney from refractory bricks. Brick and the work of laying it are much more expensive than installing an asbestos-cement pipe, but the experience of a stove maker brings certain doubts to the asbestos-cement option. Or is the master still disingenuous, lobbying for a job? What could be the advantages of a brick chimney?
Velov
https://houseinform.ru/forum/_asbestotsementnaya_truba_dlya_dyimohoda

Asbestos-cement pipes are installed on heating stoves with a temperature not exceeding three hundred degrees; these may include gas devices of low power or sections of the chimney in the upper part where the temperature has already dropped below the specified value; in your case, the stove maker advises correctly.
Baxtoon
Read also: Instructions for stove mortars (for laying chimneys): what are they and how to prepare them?
https://houseinform.ru/forum/_asbestotsementnaya_truba_dlya_dyimohoda

Ac is hydrophobic. Not durable. Does not withstand high temperatures. Easily overgrown. Not heat intensive. The baker is right.
Masha
https://houseinform.ru/forum/_asbestotsementnaya_truba_dlya_dyimohoda

The stove-maker is not lying; the chimney needs to be made of refractory brick; an asbestos-cement pipe will not withstand such a high temperature and may burst. They sell special ceramic pipes for such purposes; my friend bought one, and it cost him more than the boiler. In addition, if the chimney exits through the roof and is a round pipe, then the hole will be difficult to seal from water leakage. (I have my own bitter experience, no matter how much I smear it, it leaks, I read that you need to remove it from the brick with a rectangular masonry and then put on a metal apron)
strah https://houseinform.ru/forum/_asbestotsementnaya_truba_dlya_dyimohod

If you want it to explode sooner or later, set it... It explodes “beautifully”... I saw it myself...
shuttlehttps://www.stroiteli.info/archive/index.php/t-2975.html

DIY installation and insulation

Below are instructions for insulating and installing a chimney. First you need to stock up on materials and tools. Required:

Several smooth galvanized iron sheets. Their exact number depends on the size of the sheet and riser.
Insulation. Usually mineral or glass wool and other fibrous materials are used.
Riveter and rivets 4 mm thick.
For cutting metal, scissors or a grinder.
Drill or screwdriver
Hammer and other hand tools.

The preparatory stage has been completed, it’s time to start insulation and installation.

It is necessary to make several cylindrical protective covers. They are made from a sheet of iron. The height of one segment is 1.5 m, its diameter should exceed the thickness of the outlet by 6–8 cm. The sheet is connected into a ring using folds, and then riveted.
The outlet is cleaned of dirt, dust and other debris.
The first iron segment is placed on the lower part of the riser, and the voids are filled with insulation.
The entire pipe is sheathed in a similar way.
The chimney ends with a small roof that prevents the ingress of precipitation.

Let's start installation:

First you need to make the base. The material for it is usually cement and brick.
Next comes the installation of a revision with a hole for cleaning the system. This is only possible if the asbestos-cement pipe is the top part of the system.
After preparing the base, the riser itself is installed. Its fixation occurs both below and in the ceiling, between the beams.
An additional element is installed on the boiler, connecting it to the outlet pipe. It is usually made of metal or heat-resistant ceramics.

Attention! If the temperature of the gases leaving the boiler exceeds 300 degrees, asbestos is installed as an additional section. It should be located at a considerable distance from the exhaust source. The installation procedure is quite simple, the time costs are small, but what about the cost

Subject to the availability of the necessary tools, we will consider only the prices of materials. An asbestos-cement bend 150 mm thick, 4 m long will cost about 900 rubles

The installation procedure is quite simple, the time investment is small, but what about the cost. Subject to the availability of the necessary tools, we will consider only the prices of materials. An asbestos-cement bend 150 mm thick, 4 m long will cost about 900 rubles.

Sheet of smooth galvanized metal 1.2 by 2.5 m another 880 rub. Insulation, for example mineral wool, 500–600 rubles. per package. The exact cost will depend on prices in the city and the size of the chimney.

Is asbestos cement harmful?

Perhaps the biggest disadvantage of asbestos-cement pipes is medical contraindications. Thus, some experts argue that structures made of such material installed in a residential area can lead to cancer in the future. Although the danger has been confirmed only by the amphibole variety of asbestos. This variety cannot only be used in construction, but even mined.

Chrysolite asbestos is freely available, but it is only harmful when the dust of this material is inhaled. As a rule, only workers in workshops where such structures are produced are at risk, but when using personal protective equipment, such a risk is minimized. In addition, if such asbestos gets into the lungs within 10 days, half of it is completely eliminated, and the remaining part can cause cough, allergies and in some cases asthma, but not cancer.

The finished product is practically safe. Harmful substances that can be formed when the pipe is heated are easily removed along with smoke and combustion products, so proper installation of the chimney is important.

Why were they popular in the past?

During Soviet times, there was an acute shortage of all types of building materials. Asbestos pipes were a real boon for private developers. The purlins met all safety standards, had no worthy alternative, and were distinguished by their strength, tightness and affordable price. The links were used in furnace making, arrangement of water supply systems, sewerage systems and construction of wells.

Over time, GOST requirements were replaced by TU. Changes were made to the production technology, which negatively affected the quality characteristics of the products.

They can only be used for a gas boiler, installed in the middle and end of the chimneys of saunas and baths. But, it is better to abandon this idea and use pipes made according to specifications for arranging low-pressure communications and protective structures for laying cables.

Mechanical cleaning

This cleaning is done using special metal brushes on a long handle or scrapers. Plastic brushes will not cope with such a task, since the soot settles quite deeply.

Typically, this method does not allow you to completely clean the chimney. But if there is an inspection hatch, then this will be possible.

A cable with a cleaning tip attached to it is also used. The load simply drops all the way to the foundation. Since the chimney is strictly vertical, after a couple of approaches you can get rid of almost all the soot.

Step-by-step insulation technology

Due to the fact that chimneys come in different types and designs, we will describe how to properly insulate a chimney pipe made of brick, asbestos cement and steel.

Chimneys made of asbestos cement

Asbestos cement pipe

To understand how to insulate a chimney from an asbestos pipe, we will analyze the entire procedure step by step, following the recommendations of professional builders:

First, you need to thoroughly clean the work area from dust and dirt; The next step is to make a special folding casing for the insulation (made from galvanized iron)

When determining its parameters, it should be taken into account that at least 6 cm should remain between the pipe and the iron for insulation; Pay attention to the fact that a casing assembled from several parts is put on the asbestos pipe, and each of them should not exceed 1.5 m; First of all, you should secure the lower part of the casing and carefully fill it with sealant. Then, the second part is put on and the procedure is repeated. This design must run along the entire length of the asbestos pipe.

This design must run along the entire length of the asbestos pipe.

Thermal insulation diagram from a home craftsman

This is what an asbestos chimney with a casing looks like

Often, many cottage owners do without a casing. The pipe is simply wrapped in a roll of mineral wool and secured with staples. In order for this method of insulation to become truly reliable, several layers should be wound.

Steel chimneys

So, we seem to have sorted out the asbestos pipes, now let’s see how to insulate the metal chimney pipe. In general, many manufacturers of building materials produce ready-made chimneys made of stainless steel. The design is quite simple and consists of only two pipes of different diameters.

How to insulate a metal chimney? To do this, take a pipe of smaller diameter and insert it into a pipe of larger diameter. Then, the remaining space between the pipes is filled with any of the above types of insulation. If you are interested in modern materials, then we can recommend basalt chimney insulation, which in its structure resembles mineral wool, but is much more practical and durable.

Thermal insulation of a steel chimney

In principle, it is much easier to insulate an iron pipe than an asbestos pipe, so there should be no problems here.

Brick chimney

Insulating a brick chimney is perhaps the most complex type of all presented in this article. Now we will present several options, from which everyone will choose for themselves how to insulate a brick chimney:

Plastering method. To do this, you will need to attach a reinforced mesh to the chimney. Then prepare a solution of lime, slag and a small portion of cement. Spread the resulting solution over the entire surface of the chimney and level it (all work is done in one layer, which should be at least 3 cm).

When the solution dries, you can add a few more layers and immediately cover up the resulting cracks. To give an attractive appearance, the pipe can be whitewashed or painted in the future.

Thermal insulation diagram of a brick chimney

Insulation with mineral wool. To do this, you will need to take a roll of basalt wool and cut it into pieces that correspond to the dimensions of the chimney area. Then, the insulation is glued to the pipe using tape. The last step of the work is to lay insulation (for example, Rocklight) with a second layer of bricks or asbestos-cement slabs.

The process of thermal insulation of a chimney with mineral wool

Good luck!

Making boxes

How to insulate an iron chimney pipe was discussed earlier. Now you can move on to the next step. Many people think that making a chimney box is too difficult a task. In reality this is not the case. It is enough to approach the work responsibly and competently.

Required tools:

Drill;
Metal scissors;
Compass;
Metal sheets;
Self-tapping screws.

Stages of work:

Preparing the hole. Along the edges it is necessary to secure the bars, which will act as a support for the body.
Two blanks are cut from a metal sheet. They are given a U-shape. Then the finished parts are screwed to the ceiling using self-tapping screws.
Again, two blanks are made, but they are already secured to standing sheets with a small spade. This results in a seamless frame in the ceiling.
Now the bottom for the box is made from a metal sheet. There should be a hole for the chimney in the center of the workpiece; a compass will be needed here.
The box contains four two-centimeter fasteners. They are cut out and bent perpendicular to the bottom.
Walls are attached to the bottom. Now the chimney is inserted into the box, it is additionally secured with clamps. The voids are filled with an insulating layer.

Fire safety measures and risks

When laying an asbestos-cement channel yourself, it is necessary to strictly follow fire safety rules, since the material gets very hot and there is a risk of fire:

The installation of a chimney in the ceiling involves making a special penetration in the form of a hole in the ceiling 10 cm larger than the cross-section of the pipe. The resulting distance is filled with non-combustible material.
You can initially build a “fluff” and fill the gaps with broken bricks and sand.
To protect the roof from water leakage, the perimeter of the chimney structure must be sealed with a cement compound or a special bitumen mastic must be used. Sealing cracks with silicone is excluded.

It should be remembered that it is strictly forbidden to allow heating surfaces to come into contact with load-bearing structures and sheathing elements made of flammable materials.

Insulation of asbestos cement pipes

To complete the entire cycle of work, you will need to perform several operations:

we clean off the remaining mortar, dirt, paint from the surfaces; we assemble a ready-made steel protective device (casing), which consists of several parts and is put on the pipeline as a simple clamp of 2 parts; we put on the first part and fill the internal space with a layer of thermal insulation; Example of thermal insulation we install the following sections of the chimney , the work is carried out according to a similar scheme; at a certain distance, the pipes are fixed to the wall with self-tapping screws and dowels; after accessing the roof and before installing the protective canopy, it is necessary to close the internal space between the steel lining and the asbestos-cement pipe.

Safety

When building a chimney in a bathhouse, you first need to think about safety issues. After all, if something is done incorrectly, wooden structures can catch fire very easily. The problem must be approached carefully, then the bathhouse will last a really long time, and there will be no risk to people’s lives.

All the necessary requirements that chimneys must meet are established by the relevant sanitary rules and regulations. They specify the distance that must be maintained between the pipe and flammable parts of the roof slabs. This value depends on the pipe parameters. If you are planning to make a chimney in a bathhouse, you should familiarize yourself with SNiP 41-01-2003, which approves the rules for the installation of ventilation, heating and air conditioning

In this case, pay special attention to paragraph 6.6.22, which contains all the necessary information

To ensure that the chimney is completely safe, you need to use appropriate materials for thermal insulation:

mineral wool;
basalt cardboard;
mineralite

Non-flammable mineral wool with long service life

Fire-resistant plasterboard and glass-magnesium sheet are also suitable for this purpose.

Fire-resistant drywall can withstand exposure to direct fire for about an hour

Glass-magnesium (glass-magnesite) sheet (SML), moisture-resistant, fire-resistant, frost-resistant, environmentally friendly

You need to pay attention to some other points

So, it is important to choose the right materials from which the chimney itself will be made - they must be resistant to high temperatures. For example, if you decide to use a metal pipe to construct a chimney, it must be made of non-galvanized material

The fact is that when heated to high temperatures, zinc begins to evaporate, and its evaporation is extremely harmful to health.

For example, if you decide to use a metal pipe to construct a chimney, it must be made of non-galvanized material. The fact is that when heated to high temperatures, zinc begins to evaporate, and its evaporation is extremely harmful to health.

Replacing a brick pipe with a metal one

If a brick chimney is not enough, it can be further extended using a metal pipe. The task is labor-intensive, but completely achievable

It is important to approach it with full responsibility

To begin with, a flat steel platform with a pipe is made. Moreover, its diameter should be the same as the diameter of the metal pipe that is planned to be used. The platform must be securely secured. It is fixed with dowels and screws. Sealing will add additional reliability.

Work order:

On the brickwork you need to mark the points at which the fastening will be installed. They cannot be placed on a masonry seam. It is advisable to place them closer to the center of the brick, and not on its edge.
Holes are drilled in the marked places to place dowels. At the same points, holes are made on the flat surface; the self-tapping screws will go there.
Fireproof sealant is applied to the brick base, then a steel platform is placed there. Self-tapping screws are screwed into dowels
It is important to ensure tight fit and uniformity.
Now all that remains is to wait for the sealant to dry completely and proceed directly to extending the chimney using a metal pipe.

Important installation details:

The decision on how to insulate a metal chimney pipe should be made based on the budget, as well as the needs of the structure.

It is important to approach the task as responsibly as possible, performing work in full compliance with all standards and nuances. Then the chimney insulation will last a long time without complaints.

Heating from DESIGN PRESTIGE LLC View water here resant.ruotoplenie-dachi.html

note

Our company DESIGN PRESTIGE LLC is part of the non-profit organization ANO INTERREGIONAL BOARD OF FORENSIC EXPERTS. We also provide independent construction technical expertise services.

In order for the pipeline to serve for a long time and not have any problems with it, it is necessary to initially install the structure correctly, as well as connect asbestos-cement pipes as best and as efficiently as possible, using the necessary connecting elements, fittings and devices designed to compensate for various deformations and vibration processes .

In order to make a choice on a specific type of connecting elements, it is necessary to determine for what purposes the product made from asbestos-cement pipes will be used

It is important to determine the specific function of the pipeline structure

Manufacturing plants produce asbestos-cement couplings with two teeth, which are similar in size to the asbestos-cement elements found in the pipeline structure. These connecting elements are widely used in water supply systems. The process of combining parts occurs in a simple way, using a dense rubber ring.

In the case of connecting pipes that will not be subject to pressure during operation, asbestos-cement couplings are used. They are made from a pipe with thick walls and a large diameter. In addition, in water and gas pipelines that are made from asbestos-cement pipes, “Zhibo” couplings made of cast iron can be used.

For laying cable connections, high-pressure polyethylene couplings are used to fasten asbestos-cement products that will not be subject to pressure.

Fragment of joining: 1,2 - chrysolite-cement pipe; 3 - coupling; 4 - rubber sealing ring

Such a main element in a product as a connecting node must have the following:

1. When working with significant pressure, as well as in the case of the formation of a vacuum space, it must exhibit stable strength and have density properties.

2. Do not be influenced by an unfavorable environment.

3. Show yourself as a convenient and simple material that is not worth spending a lot of time and effort on.

Rotary cleaning

Rotary cleaning is one of the types of mechanical cleaning. There is also a brush or scraper on a long flexible rod. The structure is connected to a drill or a powerful screwdriver. High speeds can ensure thorough cleaning of the chimney and significantly save time.

Do you think an asbestos-cement chimney is safe?

Ask a question to an expert

Do-it-yourself brick chimney for a solid fuel boiler

The construction of the pipe itself is not difficult, especially for those who have already had experience working with similar material

However, during construction it is important to take into account some features that will allow you to create a reliable and durable structure. It will most effectively cope with the effects of condensation and precipitation. The height of the foundation should be at least 30 cm, and the width should be selected based on the width of the structure itself: the foundation should exceed it by 15-50 cm on each side

The height of the foundation should be at least 30 cm, and the width should be selected based on the width of the structure itself: the foundation should exceed it by 15-50 cm on each side.

If the boiler chimney becomes part of an external wall, the foundation must also extend and be the lowest level of the wall foundation.

For laying it is necessary to use refractory brick M75 or M50. To fix them, cement mortar or a mixture of cement and lime is suitable. A high-quality chimney can be obtained by performing masonry with bandaging: ensuring that the seams of the previous row overlap the next one.
During construction, it is necessary to treat the inner surface and rid it of roughness.
It is better to finish the upper part of the chimney for the boiler with a head protruding 10 cm beyond the brick base.

Ventilation holes can be added under the head to prevent air from blowing in. They must be placed on two opposite walls or on each side.

Compliance with these principles will allow you to create a chimney for a solid fuel boiler yourself, be it a straight pipe through the roof or going into the wall. Each design method has its advantages:

A chimney passing through an attic or roof will transfer heat to all rooms through which it passes, therefore it is suitable for two or more storey buildings. In addition, it is easy to construct.
A chimney passing through a wall is compact and safer than a conventional one.

Thus, brick chimneys for boilers are the most optimal when comparing the complexity, cost and reliability of construction. Therefore, having studied all the necessary information, you can purchase materials and begin building a chimney with your own hands.

Installation of passages for two-story buildings

If the building is two-story, then in this case, after installation on the first floor, it is necessary to work on the second. How to install a sandwich pipe through the second floor? Let's consider the main points of wiring a sandwich chimney through the second floor:

As a rule, the second floor of the baths is equipped as a rest room. Also, laying a sandwich chimney can take place in a private house. In such cases, a transition is made from a sandwich pipe to a single-wall pipe. This is done so that the heat from the chimney spreads and warms the rooms. The transition to a single-wall pipe should be carried out at a height of 1 m from the floor of the second floor.
In front of the attic passage unit, a transition is made back to the sandwich pipe.
The attic passage unit is installed in the same way as the previous one.
It is necessary to route the chimney through the waterproofing coating and the roof. It is imperative to carry out thermal insulation and install a protective apron, which will serve as waterproofing for the chimney sandwich. Homemade aprons and heat-resistant sealant may be suitable for these purposes.

Waterproofing after running the pipe through the roof is necessary to ensure that moisture does not penetrate into the attic and does not flow down the structure. When passing a sandwich pipe through the roof, it is also necessary to comply with the standards described in SNiP.

What are asbestos cement pipes used for?

Asbestos cement is a durable fireproof material that combines the properties of asbestos and cement. Asbestos, or, as it is also called, mountain flax, is a group of silicate class materials that look like thin, durable threads. These threads are used as a frame into which other building materials are poured or laid. In the case of asbestos cement, such a building material is cement.

Asbestos gives strength to materials and protects them from fire. There are two types of asbestos: chrysotile and amphibole. The first is widespread in Russia, where there are asbestos deposits. This material has been used in construction for about five decades. Amphibole asbestos used to be common in European countries, but has now been banned due to its negative impact on human health.

Asbestos-cement pipes are intended for those structures where there is water, steam or gas. They can withstand temperature fluctuations and, when installed correctly, last for many years.

Current state of affairs

For a long time, asbestos chimney pipes (also called asbestos-cement or asbestos-cement) were recognized as a construction material that was not only of sufficient quality, but also the least expensive among similar products. Read also: “How to connect asbestos pipes - reliable and practical options.”

The short service life of the products was not taken into account, since the low cost made it possible to purchase goods in reserve. As a result, with the general low cost and the production of products being put on stream, asbestos-cement pipes have become widespread, especially in rural areas, during the construction of country houses.

Since many buildings have survived from those times, to this day most suburban buildings are equipped with chimneys made of asbestos-cement pipes for gas boilers. The reason for this, as mentioned above, is not the excellent quality of the product, but its low cost, the possibility of quick installation and simple replacement of an element that has become unusable.

Home craftsmen are not deterred by the fact that slate, also made of asbestos, due to its mechanical strength, lightness, and durability, used for roofing, quickly bursts during a fire.

Without a doubt, bringing information to people about the dangers of using products as gas ducts, coupled with the introduction to the market of products made from modern materials, is gradually bearing fruit, but the population has not yet reached the point of completely abandoning the hazardous material.

Risks of installing asbestos chimneys

Before choosing a specific product as a chimney, it is necessary to study the risks that arise during its operation and the possibility of using it for certain purposes. So, when installing an asbestos chimney, there is a possibility:

When exposed to high temperatures, an asbestos chimney may burst. There were even cases when it exploded;
the appearance of an unpleasant odor that occurs when harmful condensation and soot are absorbed;
inability to install special hatches for cleaning and monitoring the condition of the chimney;
difficulties in removing soot that occurs during the combustion process;
thin-walled material does not contribute to the formation of draft, as a result, the boiler may not work well.

The installation of a chimney should be approached with full responsibility.
After all, this is an element of the heating system, which must work flawlessly. Improper operation of such a chimney can lead to a fire or carbon monoxide poisoning that accumulates in the pipe. That is why, before installing a chimney from an asbestos pipe, it is worth weighing all the pros and cons. And figure out in detail whether it is worth risking your health and property by installing a product that may not be intended for such purposes. vote

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Advantages of using asbestos

Let's start right away with the positive qualities of asbestos pipes, which during the development of agriculture could easily be purchased (or stolen, whichever is preferable to anyone) at many enterprises and collective farms for pennies.

Their comparative cheapness. This was due to the fact that asbestos was mined in large quantities in our country and products from it are easy to manufacture.
They are light in weight, so they are quite easy to install.
They have no seams and are not susceptible to moisture.

Asbestos chimney installation

The chimney is installed in the following order:

An asbestos pipe should never be removed directly from the kiln; it should rest on a concrete or brick base. The supply to the heating unit is made through a metal adapter. This part of the chimney is equipped with a flat damper or disc damper to regulate the draft by reducing the passage in the smoke exhaust channel.
When installing a chimney, a container is provided in its lower part to collect condensate, which must be periodically emptied of black liquid with an unpleasant odor.
For asbestos pipes, plastic or metal condensate collectors of suitable diameter can be used
The upper end of the chimney must be equipped with a cap, and in the best case, with a deflector.
At the junction with the chimney, a hatch is cut out in the ceiling, which is at least 15 centimeters larger than the dimensions of the pipe.
A sheet metal damper is fixed to the ceiling below. Basalt wool is placed tightly into the resulting opening from above and covered with the same metal sheet on top. When a pipe passes through the ceiling, a protective box of steel sheets is installed
Crossing the roofing pie is done in the same way. Only on the outside of the roofing you need to install an otter - a device to prevent water from entering through the pipe into the under-roof space. On the construction market it is easy to purchase a ready-made structure that matches the size of the pipe and the slope of the roof.

It should be remembered that chimneys made from asbestos pipes should absolutely not be used when installing heating in a bathhouse due to stoves with extremely high heating temperatures.

Fire safety

The requirements for a safe chimney installation do not differ from those for other systems:

The passage of the smoke duct closer than 70 centimeters from the load-bearing structures of the building is not allowed.
Chimneys cannot be painted with oil or enamel paint. If necessary, you can use lime or a special bitumen varnish.
When a chimney passes through a wall, it must be finished with non-combustible material, and the passage itself must be sealed in the same way as a ceiling passage.

It should be remembered that the industry does not produce asbestos-cement pipes specifically for chimneys and the owner himself bears responsibility for their use in the heating system.

Video: consequences of improper use of an asbestos chimney

An asbestos chimney should be inspected monthly and, if necessary, cleaned of soot.

What is especially important is that for chimneys made of asbestos pipes on solid fuel stoves, some preventive measures aimed at preventing planting are categorically not recommended. Do not use high-temperature fuel (aspen) or walnut shells to burn soot in the chimney, even in pyrolysis ovens

For this purpose, you need to use potato peels, rock salt or a blue mixture, which chemically destroys the soot layer.

Insulation of asbestos chimney

The purpose of insulating an asbestos chimney is to increase the temperature of the flue gases to reduce the amount of condensate released. The possibilities of this technique are not limitless, since at temperatures above 300 degrees the asbestos pipe begins to collapse.

The outer part of the pipe is insulated with mineral or basalt wool, on top of which a galvanized steel casing is placed. The advantage of this method compared to brick otter is the large difference in the weight of the structures.
The internal parts are insulated in the same way; the construction of a protective shell is not necessary here.

Fire insulation options for smoke exhaust systems

Insulation of the chimney is carried out in order to withstand the heating of the materials adjacent to it. The part of the smoke exhaust passing through the ceiling or roof is placed in a box; the distance to it should be more than 10 cm. This free space is filled with fire-resistant material with low thermal conductivity (basalt wool or fabric, asbestos fiber).

If the chimney has a prefabricated structure (steel, ceramic). then the kit must necessarily contain special elements that already have increased fire safety performance. Such modules are attached to a pipe and may have an additional reinforcing frame and a waterproofing apron for the roof. Sometimes round pipes are insulated with brickwork; for this, a window is cut in the ceiling, covered with brick in one or several layers, and the distance to the pipe is filled with mineral wool.

The release of new building materials and the development of advanced technologies are a guarantee of effective thermal insulation. The choice of materials for this purpose is largely determined by the shape of the chimney, the method of wrapping the pipe that removes hot gaseous substances when burning fuel.

The main difficulty is to prevent the materials adjacent to the chimney from overheating so that they do not ignite in any type of building.

Most buildings in private households have a chimney coming from:

solid fuel boiler;
fireplace;
ovens;
stoves for cooking.

Ceramic chimney kit
Before insulating a pipe in a bathhouse or residential building, you should choose the most suitable option for your design. A ceramic chimney is no less efficient and durable; it is used for a fireplace or bathhouse. The assembly of the finished structure includes components made from fire-resistant materials. Some of them are adjacent directly to the pipe or cover it, others are designed to seal the passage through the roof.

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The separation of the chimney and multi-layer roofing cake (with insulation, hydro- and vapor barrier) is carried out according to all modern standards:

for double metal pipes, internal insulation with mineral wool is provided; a single pipe is covered with a finished insulating shell of the required diameter and protected from the outside; in brickwork it is important to increase the thickness of the walls (38-40 cm) and protect the contacting surfaces with special plaster.

The box for the outlet of the chimney pipe is constructed from a transverse beam and rafters, maintaining a distance of at least 15 cm from the wooden structure to the metal chimney. The gap between them is filled with basalt wool.

The membranes of the roofing pie, cut at the point where the pipe exits, must be carefully cut and wrapped. Then they are pressed with lathing and secured along the edges of the box with nails. To completely seal the roof, the pipe in this place must be wrapped with a special sealing tape.

When the chimney goes through an unheated attic, and not in a residential attic, the risk of overheating of roof elements is reduced. Complete tightness of the insulation is necessary in any option, but it is better to additionally wrap the pipe with special tape. Proper installation of internal waterproofing and outer cap will ensure reliable sealing after installing thermal insulation of the chimney in the roof opening.

Pipe outlet through the roof

How to insulate an iron chimney pipe

To insulate a metal pipe outdoors, use basalt insulation and metal clamps - the rolled insulation must be wrapped around the pipe and secured with clamps after 30-40 cm. A tool that is useful for insulation:

Hammer, pliers, screwdriver, clamp, and other plumbing tools;
Tape measure, metal ruler or square, building level, pencil or marker;
A cutter or scissors to cut the insulation for chimney pipes to size;
A device for riveting and rivets that connect the casing. Instead of rivets, short press washers can be used;
Screwdriver or electric drill, drills Ø 3-4 mm for rivets;
If the chimney is being plastered, you will need: a spatula and a bucket for mortar;
To seal cracks and joints - a construction gun and bitumen mastic.

How to make an asbestos-cement chimney in a finished building?

It often happens that a chimney needs to be installed in an already constructed building, in such cases it is necessary:

A high foundation is also made under the chimney.
Appropriate holes are made in the ceilings and roof and these places are protected with a layer of non-combustible materials.
Assembling the chimney should begin from top to bottom. The very first fragment is attached to the roof structure using heat-insulated fasteners and the socket down. After installation, the area is waterproofed and the roof finishing section is assembled.
A protective cap is installed so that installation can be done during precipitation.
If the pipes were purchased without a socket in the structure, you should purchase a special metal clamp for securing the pipes.
If the pipes have a socket, the thin part of the second fragment is carefully pressed into the first upper fragment using a jack. This method will ensure a tight connection.
The joint must be carefully sealed using asbestos cord and bitumen sealant.
In the same way, the remaining fragments of the chimney are mounted up to the foundation.
The chimney is connected to the boiler pipe.

After completing the installation work, you need to check the traction. To do this, some flammable material is set on fire and placed in the firebox. If the structure is assembled correctly, the light will deviate towards the chimney.

A properly constructed chimney made from an asbestos pipe

The misconception that installing an asbestos pipe as a chimney is not difficult can lead to many undesirable consequences. Boiler equipment is different, each has its own efficiency.

Therefore, before proceeding with installation, you need to carefully study all technical conditions. What a private developer must be prepared for when making a chimney with his own hands is reliable fastening of the structure, arrangement of thermal insulation of the pipe, and compliance with fire safety standards.

Chimney insulation

Fastening a chimney from an asbestos pipe

Installation of an asbestos pipe in the general chimney system can be carried out from the area where the temperature of the combustion products does not exceed 300 degrees Celsius. It is permissible to install both a separate riser (external chimney) and a channel passing through the roof. When arranging, you must adhere to the following rules:

When the pipe extends above the ridge more than 2 meters, it is necessary to use additional clamps and braces for fixation;
A separate chimney is attached to the load-bearing wall with pipe clamps at intervals of at least half a meter;
When placing asbestos inside a brickwork channel, additional reinforcement spacers are used;
The chimney should be secured at the point where it passes through the roof using an asbestos cement bracket.

Extension of a chimney with an asbestos channel

Free-flow asbestos pipes, which are used to organize a chimney, are usually built onto a ready-made part of the chimney made of another more heat-resistant material. The transition from metal to asbestos can be accomplished through a special stainless steel sleeve.

Connecting an asbestos pipe with a coupling

If there is an extension of one asbestos pipe to another of the same type, then the connection is made using a CAM modification coupling. The coupling has two internal grooves for a heat-resistant seal. When building up a brick chimney, the CAM coupling is fixed inside the masonry. It is supported by embedded reinforcement, and the space between the masonry and the coupling is filled with concrete.

Extension of brickwork with an asbestos chimney pipe in the absence of a coupling can be done in another way. To do this, a slab of the same asbestos cement or steel with a hole not exceeding the diameter of the asbestos channel is installed on the last row of bricks. The latter is installed on top of the hole and fixed with a solution.

Thermal insulation cushion device

Asbestos cement has a porous structure. It has poor thermal insulation qualities, so it heats up very much, to the temperature of the gases being exhausted outside. Asbestos-cement chimney pipes must be insulated with fire-resistant material for the following reasons:

To avoid heating and ignition of flammable materials that make up the structure of the house;
To avoid the formation of condensation, which is one of the factors that has a destructive effect on the chimney.

Basalt wool

The classic version of insulation is based on the use of basalt wool, which is wound in several layers on the chimney and secured with special clamps or knitting wire. A layer of foil is placed on top of the cotton wool. This must be done to waterproof the pipe and provide an additional fire barrier.

The insulation can be protected using a metal frame. For this purpose, thin galvanized sheet metal or with a factory paint coating is suitable. It is advisable to use such a frame for pipes protruding above the roof, where the foil will look unaesthetic.

Inserting a tee into an asbestos-cement pipe

If the chimney is arranged in such a way that it is necessary to remove it through the side wall, add a condensate drain, or install an inspection hatch to control and clean the chimney, use tees with a coupling-type connection system. After trimming the pipes and putting on the tee, the joining gap should be filled with a composition based on acid-resistant and heat-resistant components.

Sections of the chimney made of asbestos-cement pipes are prohibited from being installed in a strictly horizontal position. When the channel exits sideways, it must slope at least 3 degrees towards the boiler installation.

Which type is suitable for which chimneys?

Recommendations from experts on the use of asbestos-cement pipes in heating systems are brief. Purlins manufactured according to modern technical conditions should not be installed indoors or directly on brick kilns. At any moment, pipes can crack and dangerous carbon monoxide can fill the room.

As for the use of different types of products, they can be installed in the following places:

Non-pressure. They have thin walls and low resistance to loads and impacts. It is better to install them inside auxiliary rooms and attics. That is, in places where people are not constantly present and there is no likelihood of mechanical damage to the highway.
Pressure. The products are more durable and pressure resistant. It is advisable to install purlins on the roof where there is wind load. Pressure pipes can be used for fireplaces and stoves, provided that they are heated with wood.

In all cases, it is necessary to pay attention to the device for smoke removal from asbestos pipes, since they tend to become clogged with soot in a short time.

The use of asbestos for a chimney. Is it possible

Pipes made from asbestos cement are needed for sewer, water, sewer and sometimes air duct installation.
Can also be used as a cable channel. Good thermal conductivity helps to use them as a casing for a local oil pipeline. When building your own home with your own hands, asbestos is used in many areas. They can be used to make piles for the foundation of a building. Asbestos-cement mixture is perfect for use in wetlands. But they are often used when installing a chimney in the house itself, sometimes in a bathhouse with heating in the form of a stove or fireplace.

To the rescue - sandwich pipes

For those who want to install a safe chimney in their bathhouse, we suggest using a sandwich pipe. This design includes several sections that can easily be placed inside each other, i.e. looks like a multi-layer cake.

Here are the main components of a sandwich pipe:

stainless steel layer (inside);
insulation in the form of basalt/mineral wool (in the middle);
steel with zinc coating (outside).

This creative design represents the insulation of a chimney built into the overall system and is designed to solve two problems simultaneously:

protection against soot accumulation inside;
maintaining optimal temperature outside.

The sandwich pipe is easy to assemble yourself and can be used for a sauna with an iron stove or bathhouse. What to do if you built a Russian steam room with a brick stove? Below we will consider how to line the pipe in this situation in order to protect it from ignition.

Technical characteristics and production of products

In practice, asbestos cement is fiber-reinforced concrete. Its production includes the following stages:

crushing asbestos raw materials obtained from mining enterprises; fluffing asbestos with further cutting of fibers; adding water to the ratio of cement to asbestos 85:15; removing the resulting pulp onto a drum with a mesh structure; winding the film on a rolling pin to give the product the required wall thickness.

The production of products takes place only under strict control in accordance with GOST. The weight of an asbestos-cement pipe per 1 m is from 6 to 11 kg. For example, the weight of 300 mm products is less than 500 mm.

The pressure pipe is produced in sections of 3.95 or 5 meters. Its flow section has the following dimensions: 100, 150, 200, 250, 300, 400 and 500 mm. The weight of the product varies from 45 kg for a 100 mm product to 67 kg for a 150 mm product or 19 kg for a 300 mm product.

Just like other products, the 300 pressure pipe is waterproof. The diameter of 300 mm allows for quick and cheap installation of the system.

Non-pressure products are produced in lengths of 3.95 m, the diameter of which ranges from 100 to 200 mm.

BNT 100 weighs 24 kg. Products 150 have a weight of 37 kg. The free-flow asbestos-cement pipe 200, whose weight does not exceed 64 kg, ensures a clean supply of water through the pipeline, which is why its installation is popular in the economic sphere.

Dry cleaning

Nowadays, you can easily purchase a chimney soot cleaner in powder form. This is a special mixture in the form of copper chloride, phosphates, ammonium salts and other elements.

The method of using this product is quite simple. Simply pour a couple of scoops of powder onto the burning wood. In this case, a reaction occurs, the chemicals begin to act on the soot and slag, forming gases and solids. Gases come out with smoke, and solid particles fall into the firebox, from where they are removed along with the ash.

Typically, such prevention is carried out every 5 ignitions, then the pipes will be clean. There are also special logs on sale impregnated with these substances, so prevention will not be burdensome.

Disadvantages of asbestos pipes

Despite its popularity in private construction, a chimney made from this material has many disadvantages.

The quality of the pipeline installation also matters. Let's consider the characteristic disadvantages of asbestos-cement chimneys and the reasons for their occurrence.

Burnout and bursting

Initially, the products were developed for mass production for use in land reclamation, construction of sewers and low-pressure gas pipelines. The designers did not provide for their operation at high temperatures. Emphasis was placed on tightness and ease of installation of highways.

The basis of the material is cement, and it is a porous material. It absorbs creosote, which is a flammable material. With strong heating, the process of its combustion begins, as a result of which the structure of the walls changes, they become thinner and burn out.

With further heating, the pressure of the air enclosed in the walls of the purlins increases. Products crack, burst and even explode.

Maintenance difficulties

The high strength of asbestos cement is a myth that many people want to believe.

Working with links requires increased caution and accuracy. The lack of steel reinforcement makes them extremely brittle and brittle, regardless of diameter and type

And that's not all...

Chimney maintenance is associated with the following difficulties:

the need for regular cleaning, since pipes literally attract soot;
the inability to make inspection windows to reach hard-to-reach areas;
sensitivity of products to shocks and loads;
Frequent replacement of insulation, which is destroyed by chemically aggressive condensate.

Humidification of the pipeline is fraught with unpleasant consequences, both for communications and for the building as a whole.

Condensate

The main purpose of the products was the laying of open and underground water pipelines of various lengths. Asbestos-cement pipes are resistant to water, but quickly collapse when in contact with chemically active liquids. They are the ones that form on the surface of the chimney during the interaction of soot and condensate.

The aggressive solution flows onto the roof and is absorbed into its surface. As a result, stains, unpleasant odors and cracks appear. Watching the video below will help you understand the extent of the damage caused by condensation. This issue can be resolved with the help of properly carried out insulation.

Insulating materials for bath pipes

Moisture and smoke generated during fuel combustion are aggressive factors affecting a brick chimney. The temperature difference during the cold season and the accumulated moisture settling on the walls fills microcracks with water, and the stone structure collapses from the inside. Small ice crystals press from the inside and destroy it.

An insulated chimney can eliminate this. During the combustion process, condensate, which contains a chemical series of oxides, forms on the surface of the flue. When interacting, the elements form weak acids (carbonic, sulfuric, etc.) that can destroy the metal surface. It is for this reason that chimney insulation is necessary.

The main question for owners of country houses with an autonomous heating system is how to insulate the chimney. In order to reliably insulate outlets for a stove or boiler, materials with a high degree of thermal insulation are used to ensure the thermal balance of the stove pipe on the roof.

Relevant for chimney insulation using mineral wool or basalt. The insulation is obtained from the melt of volcanic rock - gabbo-basalt. It is converted into fibers, due to which the insulating material has the following advantages:

retains up to 95% heat;
characterized by good permeability of escaping steam;
is characterized by chemical and corrosion resistance;
prevents the growth of fungus and mold on the surface of the chimney on the roof;
vibration and heat resistant;
made from environmental materials;
is not subject to destruction under the influence of ultraviolet radiation.

Metal “armor” in the form of a pipe made of stainless steel is used as an insulation option. It is capable of providing complete protection from mechanical damage, moisture and other aggressive factors. The chimney casing is mounted on a pipe on the roof. The interpipe space is filled with basalt wool, the outside is covered with insulation, 5 cm thick. An asbestos chimney can be wrapped with this insulation.

Wooden shields

Wooden panels are considered one of the simplest options for insulating a chimney pipe. Thermal insulation is made in the form of a wooden frame made of plates of the appropriate size. Slate or other flooring is fixed on top of it, from which the roof of the dwelling is made. After the pipe is completely covered with wood, the empty cavity is filled with felt, slag, sand, and mineral wool. Frame seams must be covered with a waterproofing compound.

Insulating a chimney in a private house using reinforced and slag concrete slabs ensures the smallest distance between joints on the structure. The space inside and corners are reinforced with mesh or wire, gypsum, clay and sand are poured in the form of a solution. Plaster is applied over the tile insulation.

Since bath buildings are often built of wood, these objects require insulation of chimneys, stoves, ceilings, and walls, since this material is highly flammable. You need to think about how to protect the pipe in the bathhouse by insulating the smoke exhaust structure so that it cools more slowly and condensation does not collect on it.

When solving the problem of how to wrap a metal chimney pipe in a bathhouse, experts highlight foil insulation and thermal insulation.