Do-it-yourself insulation of chimney pipes. How to properly insulate a chimney pipe with your own hands and why do it? Plastering a brick pipe

In summer, the chimney can perform its functions without problems. But with the onset of the first serious frosts, the situation will change. The chimney protrudes above the building and is constantly exposed to wind and moisture. Temperature changes and high humidity will begin to destroy the materials from which the chimney is built. First, cracks will appear, then entire pieces of plaster will begin to fall off.

Why is a chimney installed? To remove smoke and other combustion products into the atmosphere. When you light a stove or fireplace, a certain amount of oxygen vapor accumulates in the chimney as a result of combustion. In winter, the amount of steam increases.
Everyone knows what condensation is. As a result of the combustion of wood or coal, several types of acids are formed, which also fall on the walls of the structure as a result of steam condensation. We get a very aggressive mixture of condensate and acid, which will quickly destroy building materials.
Chimney collapse is not the only problem that can be expected from a malfunctioning chimney. The formation of steam inside the chimney leads to smoke in the stove. You will have to constantly ventilate the heated room. If the amount of steam in the chimney reaches a critical level, an explosion may even occur due to excessively high pressure.
To prevent such consequences, you should think about how to insulate the chimney.
Many private houses are built of brick. This building material is still unrivaled. The chimneys in these buildings are also brick. The question arises whether it is necessary to insulate a brick chimney. It is necessary to insulate a brick chimney, but this can be done in various ways.

The first method of insulating a brick chimney is plastering. A solution of lime and slag should be prepared and applied to the brickwork in a layer of 3 to 4 centimeters. A layer of plaster will reduce heat loss by a quarter. We have already said that the chimney structure is constantly exposed to the influence of precipitation and wind. In order for the plaster to adhere well, it should be applied to the mesh.

• We attach a reinforced mesh to the brick surface;
• prepare slag-lime solution;
• Apply several layers of plaster to the mesh.

Typically 3 to 5 layers of plaster are applied. The first layer should be the most liquid, subsequent layers should be thicker.
We have already said that a layer of plaster can only retain 25% of the heat. There is a more effective method of insulating a brick chimney. We'll tell you how to insulate a chimney with slab insulation.
The sequence of work can be described as follows:

• the brick pipe is covered with insulation boards; you can use basalt or mineral wool mats;
• the insulation is lined with asbestos-cement slabs or using brickwork;
• At the final stage, the structure is plastered.

As you can see, the second method of insulating a brick chimney is more complicated, but the efficiency of this design allows you to retain up to 50% of the heat.
Such an insulating design will significantly reduce the amount of condensation and will effectively prevent destructive processes.

Variety of insulating materials for baths
Folgoizol
Teploizol
Sandwich pipe as a chimney
Method of insulating a chimney in a Russian bath
Insulation of the stove in the bathhouse

The operation of the bathhouse must be absolutely safe for humans. To prevent fires from coming into contact with a hot stove or chimney pipe, walls and ceilings, as well as hot surfaces, should be thoroughly insulated. We will tell you in detail how to insulate a chimney pipe in a sauna in this article.

As sad statistics say, during 2014, up to 70% of fires in private baths occurred due to incorrect thermal insulation of metal pipes. Therefore, to help our readers protect themselves and their guests, we will tell you about the materials, as well as the technology for insulating pipes in a bathhouse.

The favorite material for bathhouses in Russia is wood. However, it tends to be very flammable. To avoid this, people have long learned to insulate the chimney in the bathhouse, as well as the stove and all surfaces - walls, ceilings. For these purposes, any available means were used - clay, asbestos or any other non-flammable materials with a low degree of thermal conductivity.

Another argument in favor of thermal insulation of the chimney is that in this case the pipe will cool much more slowly and condensation will not accumulate in it.

It is a mistake to think that a good solution regarding how to insulate a pipe in a bathhouse would be to mount sheet iron on the ceiling. The metal can heat up very quickly, which in no way prevents fire, so it is not suitable for thermal insulation.

As an alternative to lining the pipe in the bathhouse, you can use red refractory brick.

Thermal insulation of the chimney in the ceiling! HOW???

However, for such a design it is necessary to foresee the size of the room in advance, strengthen the foundation and select a design.

Among the modern materials that solve the question of how to wrap a metal chimney pipe in a bathhouse, the following are offered on the market:

Let's look at each of them in more detail.

Folgoizol

It is a two-layer material consisting of a heat-insulating component and foil. Thanks to the reflective layer, the room does not cool down so quickly, because up to 90% of the heat is retained inside the bath, so it is a very high-quality insulator.

Folgoizol is highly environmentally friendly, because thick food foil is used as a raw material. This material is not afraid of ultraviolet radiation and strong temperature changes - the operating range is from -65 ºС to +175 ºС. Therefore, it will be a completely worthy choice for wrapping a pipe in a bathhouse.

Note that foil insulation is often installed not only around the chimney, but also on the walls and ceiling of the steam room. It serves for high-quality vapor and waterproofing, and also insulates the bathhouse well.

The sauna, lined with foil insulation, can be compared to a thermos based on its operating principle. It heats up quickly and cools down very slowly.

Teploizol

One of the options for wrapping a pipe in a bathhouse is thermal insulation. To produce thermal insulation, foamed polyethylene is used, hidden between two layers of foil, and the top layer of foil in the material is designed to protect the chimney from overheating.

Teploizol appeared on the building materials market relatively recently. The thickness of such material ranges from 2-10 mm.

Thermal insulation is easy to manipulate - you just need to wrap it around the chimney and secure it with metallized tape.

Sandwich pipe as a chimney

Recently, various manufacturers have begun to produce new safe sandwich pipes for baths and saunas. With such a design, there is no longer any need to worry about how to protect the pipe in the bathhouse (more details: “Advantages of a pipe for a sandwich bathhouse when building a chimney”). The design of such pipes involves quick and convenient assembly of sections inserted into each other. Moreover, it is optimal to use such pipes with an iron stove.

The sandwich pipe is a multilayer structure, inside of which there is a stainless steel frame, then insulation made of mineral or basalt wool is laid, and a galvanized casing is placed on top. Thanks to this structure, soot does not accumulate inside the chimney, the outer layer of metal does not experience overheating, and the entire structure looks beautiful and laconic.

However, we note that it is advisable to install sandwich pipes in dry saunas. But for traditional Russian baths with high humidity, you should choose slightly different thermal insulation options.

Method of insulating a chimney in a Russian bath

If a heater is installed in the bathhouse, then fire-resistant bricks are used to build the chimney. It is able to remain warm for a long time.

When building a brick chimney, you should not save, but it is advisable to approach this issue very responsibly, because its durability depends on the quality of the work performed.

In this case, the best way to isolate a pipe in a bathhouse from the ceiling, roof and other roof elements is to attach sheet metal to these surfaces.

Where the chimney comes into contact with the roof and ceiling, the surfaces should be protected with asbestos sheets. On the walls near the pipe you need to fasten sheets of galvanized steel. It is not advisable to use iron in this case, since it is susceptible to corrosion. Read also: “How to make a chimney in a bathhouse through a wall - device options.”

As an option, you can install a protective screen around the chimney into which expanded clay can be poured. It will serve as additional fire protection for all wooden surfaces of the bathhouse, and will also serve as a heat accumulator.

However, complete safety in a bathhouse cannot be achieved by insulating pipes alone. Similar actions must be performed with the stove, walls and ceiling.

Insulation of the stove in the bathhouse

Currently, bathhouses often use simple metal stoves, which are lined with sheet metal on the sides and back, and installed directly on the foundation. To ensure that heat is retained in the bathhouse for a long time and to make it presentable, the stove can be lined with red refractory bricks.

Currently, asbestos sheets are no longer used for stove insulation, since it releases toxic substances when heated.

It is advisable to use natural felt to insulate the stove. Although this material is quite expensive, it is an excellent insulator. In addition, when a spark hits the felt, it does not flare up, but begins to smolder, so you will immediately notice the problem by the characteristic pungent odor.

When installing the stove on a wooden floor, you should first lay felt in two layers, and then lay the brick in three rows. Sheet metal is mounted on the walls and floor around the stove in pieces 50-70 cm high.

We hope that this article was able to answer the most frequently asked questions among novice builders. Let us remind you that high-quality thermal insulation of the chimney, stove, as well as all surfaces of the bathhouse will not only keep you warm longer, but also protect yourself and your loved ones.

Protective materials for wooden structures
Furnace pipe insulation: teploizol
You can wrap the chimney with foil insulation
To the rescue - sandwich pipes
Pipe insulation in a traditional Russian bathhouse
Fire protection of the furnace

If you decide to build a bathhouse, then do not forget about high-quality insulation of the stove, chimney, walls and ceiling. Otherwise, you may have serious problems with fire in the ceiling of the building. Therefore, we will try to dwell in more detail on a pressing problem today - insulating a pipe in a bathhouse with our own hands.

Protective materials for wooden structures

Due to the fact that the chimney and stove heat up quickly, a fire may occur. Moreover, according to tradition, the material for the bathhouse is wood. Back in the old days, it was customary to insulate the walls, ceiling, stove, chimney with an asbestos layer, clay and other available materials that conduct thermal energy rather poorly and are resistant to elevated temperatures.

So how to cover the stove pipe today? Insulation of the chimney structure is necessary both for fire safety and protection from condensation, so that cooling occurs more slowly and the smoke exhaust system lasts longer.

It is a mistaken belief that several metal sheets used to cover the ceiling around the chimney will be enough to insulate from fire.

How and with what to insulate a chimney pipe

After all, metal also heats up quickly, so it will not protect against fire, and it will also not be suitable as a heat insulator.

Red brick is not always needed for pipe lining, although it is endowed with excellent thermal insulation properties. The reason is that such a design does not match the design of every bathhouse.

To better understand how to wrap a chimney pipe against fire, consider two options for insulating materials in the form:

Furnace pipe insulation: teploizol

This is a unique material, the structure of which includes foamed polyethylene, located between a pair of sheets of foil. Using thermal insulation, you can qualitatively insulate a chimney, and do it yourself.

The thickness of the thermal insulation varies from 2 to 10 mm, and the thicker the material, the greater its resistance to high temperatures.

The top layer of foil serves as reliable protection for the pipe from significant overheating. Using wire or adhesive tape, a metal craftsman attaches thermal insulation, which is then wrapped around the chimney.

You can wrap the chimney with foil insulation

Modern material includes two layers: heat insulator and foil. The second one plays a reflective function and can save up to 90% of the thermal energy in the building. Folgoizol is a harmless material compared to other analogues, since the foil is compacted food grade. The material is resistant to ultraviolet radiation and elevated temperatures within the range of -65 to +175 degrees Celsius, a good insulator.

For those who don’t yet know how to insulate a chimney pipe in a sauna, we recommend covering the steam room ceiling, walls and chimney with foil insulation. As a result, you will get a room whose design resembles a thermos. The heat will remain in the sauna, but the bathhouse will quickly gain temperature and then slowly cool down.

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.

Pipe insulation in a traditional Russian bathhouse

At elevated temperatures, fire-resistant red brick retains its performance properties, therefore it is in demand when constructing a chimney in a bathhouse with a stone stove. In this case, you are guaranteed protection of the pipe from fire and long-term heat retention.

The service life of the structure depends on how well the brick pipe is constructed. Do not skimp on materials during the construction of the chimney, because... Then the repair will cost you much more.

Let's take a closer look at how to insulate a pipe in a bathhouse from the ceiling:

1. Use asbestos to cover the pipe outlet on the ceiling and through the roof.
2. Using galvanized material, insulate the walls on the inside of the pipe. Standard iron sheets are completely unsuitable for this purpose due to their tendency to corrosion.
3. Make a box around the pipe where it passes through the ceiling.
4. Pour expanded clay inside the box to retain heat and protect the wooden floors from fire.

You have professionally wrapped the pipe, but this is not the end of the chimney installation work. The next step is measures to insulate the stove, ceiling and walls of the bathhouse.

Fire protection of the furnace

Modern metal stoves are mounted on a foundation, while sheathing the walls on the back and sides with sheets of the same material. If you cover the stove yourself with only metal, its appearance will not be very aesthetic. It is better to make external masonry with red brick, which insulates the stove from fire and retains heat in the bathhouse.

Due to the fact that asbestos releases toxic substances at elevated temperatures, it is not recommended for use in a steam room. Natural felt is considered harmless and is also a good insulator. In terms of price, this material is more expensive than asbestos sheets, and when smoldering it emits a specific smell (felt does not catch fire), which can be immediately felt.

If you intend to install the stove on a wooden floor, then first it is better to lay felt material in a couple of layers, then lay brick in three rows. For walls and floors, it is recommended to lay metal sheets as an insulator, the height of which varies from 50 to 70 cm.

How to wrap a chimney pipe to prevent fire

How to insulate a metal chimney pipe for a bathhouse?

Dear visitor! You are in the archive of the old forum on mastergrad.com

How to cover the walls around the stove in a bathhouse

Alexey777 Aug 30 2005 07:59:49	flat slate, asbestos (I really didn’t find it in the sheets, but it seems like there should be), drywall, something else? metal stove
A. Meshcheksky (Troitsk) Aug 30 2005 08:52:42	How far from the walls?
Alexey777 Aug 30 2005 09:04:02	on one side (on the side of the stove) along the entire height from the wall 20cm and on the front side of the stove the height from the middle to the top of the stove from the wall is 5 cm.
YourOK (Moscow) Aug 30 2005 09:56:25	2Aleksey777: Slate can shoot out, asbestos is harmful... In my embrasure around the Buleryan firebox it is lined with red brick, inside the steam room - half the height of the stove (to the water tank), too, but facing. The joints with wood are filled with clay and covered with platband. If the stones and/or the chimney are close to the wall, it - the wall - should be covered with some kind of sheet material so that there are no dark spots; I have a duralumin sheet folded in half. Well, up on the ceiling, too, as firefighters teach.
Romson (Saint Petersburg) Aug 30 2005 10:16:24	2Aleksey777: With such a small distance from the wall, you need to make a heat-insulating sandwich. You can make it from a metal sheet, preferably from polished aluminum or stainless steel, they reflect heat well. This is done like this: cut a metal tube into 20 mm pieces. These will be spacer washers for the sheets. Now there is 20 mm basalt insulation from the wall. and a sheet on these washers, then an air gap and another sheet on the washers.
AA (Moscow) Aug 30 2005 10:18:13	It is also important to take into account the design of the furnace. If the oven is a convection type, it means it has double walls, and the temperature of the outer walls is low. If the stove is based on the principle of a conventional potbelly stove, then the radiation from the walls is high, and serious protection is needed. The optimal (and beautiful) brick is flat or “on edge” with an air gap from the stove along the entire height. You can use metal (stainless steel is better, but more expensive) with a gap from the combustible wall surface of at least 10 mm. Gaps at the bottom and top are required to ensure convection air flow. Galvanizing is not allowed - it is harmful. Cheap, but not so aesthetically pleasing - a sheet of DSP. Installation is similar to metal.
WIK Aug 30 2005 10:29:57	Is it necessary to lay basalt wool under the CBPB sheet? (similar to a stainless steel sheet?)
YourOK (Moscow) Aug 30 2005 10:46:32	2Aleksey777: Ahh... I thought that we were talking about sealing the opening in the wall through which the stove firebox goes into another room - as is normally done... Alexey, you haven’t clearly outlined the situation with the stove - its design and installation diagram are unclear, where the gaps are - it’s not at all clear: by the way, why is the “front side” of it facing the wall?? Well, protecting the wall in the steam room is not the most difficult thing in this matter, it’s the same sandwich if the brick doesn’t fit...
Alexey777 Aug 30 2005 10:54:16	thanks for the advice, I’ll do the front with iron, in principle there’s already a heater there, the combustible surface is lower, and on the side there is a brick to the wall to the middle, and from the middle there is probably also iron.
Alexey777 Aug 30 2005 11:00:49	2YourOK: the front side that is higher than the firebox already goes to the wall, but what is lower is the same. In the picture, side A is the front, B is the side. picture
YourOK (Moscow) Aug 30 2005 11:22:09	2Aleksey777: Well, finally... now it’s clear :-)) A gap B = 20 cm is enough, IMHO, not to protect the wall. The main thing is to correctly seal the opening. Once again - good luck!
AA (Moscow) Aug 30 2005 11:47:33	2WIK: “Is it necessary to lay basalt wool under the CBPB sheet? (similar to a stainless steel sheet?)" No need. An air gap is needed so that air can circulate from bottom to top between the burning surface and the protective sheet. Or you are making a sandwich panel. Two sheets of metal or, for example, DSP, with basalt wool between them. (In the case described, I consider this to be reinsurance.) But even in this case, a gap between the panel and the wall is desirable. It is safer because it provides constant cooling with circulating air. Cutting with filler (for example, basalt wool) is done where it is necessary to ensure the tightness of the structure: passages through the ceiling, walls, etc.
Romson (Saint Petersburg) Aug 30 2005 12:22:49	2AA: I would lay it everywhere with cotton wool. Such matters are important that I think there is no point in saving on fire safety. At my place, I sewed everything around the stove 1 meter high and the height and width of two chimneys.
YourOK (Moscow) Aug 31 2005 11:30:34	2Romson: That's right... I hope everything is ok in the attic by the chimney too? PS fire is a terrible thing... last week we were extinguishing a utility block at a neighbor's dacha... we really didn't extinguish it - it was no longer possible, it was burning so much that it was pointless to water, and it was impossible to come close and throw a bucket of water - it was hot... we just watered the wall of his house , so as not to catch fire, because his utility block is only 2 meters from the house... So it's better to be safe than UNDER...
AA (Moscow) Aug 31 2005 16:43:42	2Romson,2YourOK: Nobody argues about security. I insisted on providing an air gap for free air circulation. This is noticeably more effective than just a thick enclosing structure, and also saves space. If there is no air gap, then the furnace gradually heats up a nearby wall with radiant heat, and we simply don’t know what is happening there in the depths. In addition, this design retains heat for a long time, and the risk of fire depends on two conditions: temperature and exposure time. I have already written in this forum (though they did not agree with me) that there are known cases of so-called spontaneous combustion during prolonged exposure to temperatures of only 100 degrees. This is a scientific fact. And this is possible if heat removal from the heated object is not ensured.
Romson (Saint Petersburg) Aug 31 2005 18:31:00	2AA: Read carefully: “Now the basalt insulation from the wall is 20 mm. and a sheet on these washers, then an air gap and another sheet on the washers.”
Serg (Samara, Russia) Aug 31 2005 22:01:42	2AA: > there are known cases of so-called spontaneous combustion during prolonged exposure to temperatures of only 100 degrees. This is a scientific fact. So what to do? Best regards, Sergei
AA (Moscow) 1 Sep. 2005 10:51:25	2Serg: > There are known cases of so-called spontaneous combustion of people - the object is, in principle, non-flammable - too wet, temperature ~37 degrees. Scientific fact. So what to do? Drink more raspberry tea or take an aspirin tablet. But more often they burn at a temperature of 40 degrees :-)) 2Romson: I paid attention to the washers. I simply wrote about reasonable sufficiency under the conditions that were given. This refers to the side wall. And if the metal stove does not have a protective convection screen (double walls), then the side protection must be made of two sheets with spaces between them, both from the wall and from the stove. On the firebox side, naturally, it is better to make part of the wall (along the height of the stove) from fireproof material. And then, without knowing all the conditions, it is difficult to draw an unambiguous conclusion. We offer options - the owner makes the decision.
WIK 1 Sep. 2005 12:09:23	Are two sheets of basalt wool (asbestos sheet) enough, or do you need brick protection on the side?
AA (Moscow) 1 Sep. 2005 13:21:42	2WIK: Describe the installation conditions, type of stove, wall material. We must proceed from this. If the stove is factory-made, then the instructions should indicate the minimum distances to combustible structures. But they are usually stupidly taken from SNIPs without taking into account all the listed conditions and they can be reduced by using fireproof cuttings. Read all of the above again and make a decision, bearing in mind that for a restful sleep there is no such thing as little protection.
AA (Moscow) 1 Sep. 2005 13:34:25	SNIP http://www.rusbani.ru/snip/2_04_05_91.html
petr78 (Moscow) 20 Sep. 2005 21:10:56	dear! In my bathhouse there is a wall made of timber, at a distance of 30 cm there is an iron stove. To protect against fire, I want to punch a metal sheet onto the wall, then lay a facing brick (half a brick thick) with a gap of 10-15 mm. Question: is this enough to protect the timber wall from fire?
YourOK (Moscow) 21 Sep. 2005 10:42:26	2petr78: Does the stove have a double wall? gets very hot - red hot? At first glance - sheet + brick = too much... If it heats up slightly (have you already heated it?) - below 100 degrees. - then one sheet, but with an air gap of 2-3 cm from the tree, will be enough. Although your 30 cm is quite enough to do nothing at all, you will see over time, if anything happens, take extra. measures. This has already been discussed above - read it. Is brick for beauty? Maybe nothing will happen - if you also cover the stove itself (Buleryan?) about 0.5 meters from the floor, with a gap of 1-2 cm from the iron - there will be less IR radiation and so that its crooked legs are not visible - up to the water heating tank ... But then the leaf is of no use. But with the firebox it’s not clear - where does it go? The main problem with it is when it goes through the wall into the adjoining room...

Since every private house has gas or stove heating, very often, in order to increase the efficiency of its operation, it becomes necessary to insulate a chimney made of brick or a large-diameter metal pipe. These activities should be planned at the design or construction stage.

But even after the roofing work is completed, it will not be too late to insulate the chimney pipe. For these purposes, it is advisable to use modern thermal insulation materials or ready-made products, on a soft or hard frame of which a layer of insulation is applied. Regardless of the chosen method, this will allow you to do all the necessary work efficiently and quickly with your own hands and extend the service life of the chimney.

Features of the operation of the chimney pipe

If the chimney exhaust runs exclusively outside the house, then it takes longer to warm up, and during this time more moisture will be released from the exhaust gases and settle along with harmful substances on the inner surface of the walls. For this reason, insulation must be of the highest quality. To cover metal and asbestos pipes, you should choose ready-made heat-insulating cylinders, and for brickwork - basalt or mineral wool, EPS boards.

There are several reasons explaining why it is necessary to insulate the chimney:

• Dew point (moisture condensation). When warm exhaust gases come into contact with the cold walls of the chimney, moisture is formed, which settles on the walls, is absorbed into the material and reduces its characteristics and service life.
• Aggressive environment. During the combustion process, active chemicals are released, which, when combined with moisture, form weak solutions of nitric and sulfuric acid. Having a negative impact on the entire chimney system for a long time, they can lead to its destruction (even pipes made of stainless steel).
• Formation of deposits. Without insulation, layers appear on the internal walls of the chimney, which reduce its flow diameter, and the draft becomes worse.
• Energy saving. Warming up the pipe requires less heat, which leads to lower fuel consumption, and it is easier to maintain a constant temperature in the combustion chamber.
• Thermal insulation installed outside the chimney increases the strength and stability of the entire structure, especially thin-walled metal chimneys.

The most widely used types of insulation materials are those that are completely ready for installation and those that require protection from the external environment. The first type includes cylinders, on the walls of which a layer of thermal insulation is applied, and shells filled with EPS (extruded polystyrene foam). For the second - soft basalt insulation and mineral wool.

Before carrying out work in the attic, you should check the reliability of the connections of all sections of the chimney, especially those made of metal, and cover them with insulation to prevent the impact of high temperatures on the wooden elements of the roof.

When choosing a material, it is necessary to take into account the operating conditions. The most important indicator is t of exhaust gases. The higher it is, the thinner the layer of thermal insulation can be used, but the insulation must be fireproof and non-flammable.

Insulation of a chimney made of metal pipes

Thermal insulation of chimneys of fireplaces and stoves, which are not the main source of heating and are used periodically, and brick pipes is carried out quite simply - their surfaces are plastered. But if the house has a gas boiler or a similar heating device using any other fuel, then sandwich chimneys are installed. Their price is quite high, so you can make them yourself from stainless steel.

Any materials can be used to insulate a chimney made from a metal pipe, but for one made from an asbestos pipe - mineral wool. Asbestos resists heat well and is not flammable, so it is enough to wrap it with insulation of the required thickness and cover it with galvanized sheets. The disadvantages of the material include the ability to absorb moisture and the rough surface of the walls, which increases the likelihood of deposits.

The situation is somewhat more complicated when using bulk material for thermal insulation, since a protective casing will need to be mounted around the pipe, which will also serve as a frame, and then insulation will need to be poured into it. To prevent moisture from getting inside, the gap between the casing and the pipe in the upper part is filled with cement mortar.

Do-it-yourself lining is carried out as follows:

• Prepare mineral or basalt wool and steel pipes (sleeves), preferably galvanized. Their diameter should exceed the dimensions of the chimney by several centimeters, but not more than 10.
• The chimney is covered with a layer of insulating material, the thickness of which should be above 5 cm.
• Fix with foil tape or any soft wire.
• A protective casing is put on the insulation. The edges of the sleeve, made of thin metal, can be secured with self-tapping screws or using tightening belts.
• The gap in the upper part of the chimney, which formed between the insulation and the protective casing, is filled with cement mortar to prevent moisture from entering the structure.

Making a thermal insulation cylinder

If there is a need to make a sandwich chimney yourself, then take two pipes - one of a smaller diameter and the other of a larger one. The smaller workpiece through which the exhaust gases will move must be made of high-quality stainless steel with special additives and be well resistant to aggressive compounds and high temperatures.

The outer protective casing is made from a larger pipe. Basalt insulation is placed tightly in the distance between the workpieces (it is made within 6–10 cm). If the temperature of the outlet gases is very high, then loose basal is used. cotton wool Since it does not contain flammable binders, it can withstand heat loads up to 900° C.

Insulation of brick chimneys

Brick has characteristics similar to asbestos and is able to absorb moisture. The surface of the chimney can be plastered or insulated with cotton wool, but it is better to use both options, it will be more correct and reliable. The finishing method should be determined at the design stage of the smoke system and, if possible, provide for the laying of wire for fasteners, ease of access and convenience of work.

When starting plastering, the pipe from the street is cleaned of dust, cracks and chips are repaired. If this is not done, the quality of thermal insulation will decrease. Further:

• prepare the mixture in the proportions specified by the manufacturer, first pouring water into the container and then adding the dry ingredients;
• using a spatula or trowel, it is distributed pointwise over the surface of the pipe and leveled;
• they are covered with a reinforcing mesh, securing it in the spots of the solution;
• apply the first layer of plaster, trying to cover the entire chimney without gaps, level it and leave to dry;
• after this, to ensure good thermal insulation, the operation is repeated, applying several more layers;
• When the pipe is completely dry, it is painted in the color of the roof.

Insulation can be carried out with basalt (stone) wool, which has high fire resistance. It is suitable for work in the attic and outside the house. In an enclosed space, where there is no excessive moisture and no intense air movement, it is enough to cover the chimney with cotton wool mats, securing them with metal strips. But after insulation on the outside of the house, the basalt should be additionally protected from the effects of weather and atmospheric phenomena.

For this reason, when choosing a material, preference is given to denser insulation, although its price is higher, but such mats are easier to work with and hold their shape well. Fastening is carried out using a solution. The use of foam is unacceptable - it has low fire resistance, and under the influence of high temperatures it quickly collapses.

Additionally, mineral wool slabs can be secured using dowel mushrooms. Finally, the entire structure is sheathed with corrugated sheets, but always leaving a small ventilation gap of 20 mm. Its presence will help remove moisture and prevent the slab from settling. Sometimes it is necessary to construct a sheathing, on which the chimney is supported with brick, cinder-concrete slabs and metal siding. But this method is too labor-intensive, so it is not widely used.

Another material that is actively used for external insulation is extruded polystyrene foam. It is distinguished by good density, it does not allow moisture to pass through, but when choosing EPS, it is better to give preference to products with a high degree of flammability - with a value not lower than G3-G4.

Equipping a private home with a gas or solid fuel boiler or stove heating requires high-quality performance of such work in all respects. Heating efficiency depends not only on the power of the heating system, its type and the presence of modern materials in the design, but also on the quality of the thermal insulation of the heated room and its structural elements. The chimney is an element of the heating system, which, along with the boiler or firebox, is subject to the harmful effects of combustion products, combustion temperatures and ambient temperatures. Insulating the chimney helps to minimize the effect of temperature changes on the chimney design, making it more efficient in terms of heat retention and more aesthetically pleasing in the overall appearance of the building. We will talk about how to properly insulate with your own hands. What materials to choose, their advantages and disadvantages.

Why do you need to insulate your chimney?

The smoke exhaust system from a stove or boilers of various types is based on the main building element - the chimney. Chimneys are made of metal, asbestos, galvanized pipes and brick. During operation, chimneys are exposed to elevated temperatures and seasonal ambient temperatures. In cold weather, when the chimney works intensively for its intended purpose, it is most actively exposed to the influence of temperature differences. The amplitude ranges from + 200 degrees or more to - 35 degrees. Constant heating and sudden cooling leads to a cyclic change in the structure of the molecular lattice of the material from which the chimney is made. A material, be it metal or brick, expands when heated and contracts when cooled.

The inside of the chimney is also susceptible to moisture. Not the absolute amount of moisture from combustion materials enters the atmosphere. A certain amount of it often settles on the inner walls of the chimney. As condensation accumulates, it becomes a constant phenomenon and takes an active part in the destruction of the walls (especially brick) of the chimney.

Such processes negatively affect the integrity of the chimney structure. Adding here the natural weathering of building materials and the action of aggressive components of combustion products deposited on the inner walls of the chimney, we understand that the durability of chimneys is a very dubious indicator.

Long-term effects of moisture, weathering and temperature differences on an unprotected chimney

But there is a solution to the problem. It does not eliminate the entire complex of aggressive factors, but effectively copes with most of them. Insulation is able to delay the action of destructive chemical and physical processes and largely minimize their effect.

Advantages of insulation

The insulated design of the chimney not only acquires protection from harmful factors, but also becomes more effective in terms of useful action. The retained heat naturally increases the efficiency of the entire heating system.

Having completed the insulation, you will not have to waste time and money on periodic chimney repairs.

Roof elements located in close proximity to the chimney will no longer be exposed to hot temperatures emanating from it.

Another advantage is that the chimney can be made to match the overall aesthetic appearance of the building, be it a private house or just a garage.

Another pressing reason for insulating modern buildings, in particular chimneys, is the amount of heat loss passing through it.

Heat loss through an uninsulated chimney is 20–25%

What insulation materials exist?

The choice of material for insulation will perhaps be the most decisive factor in the entire work. The complexity of the installation process, the effectiveness of the result and the appearance depend on the selected material.

The following materials are used for insulating chimneys:

• mineral wool insulation;
• fiber insulation;
• slag concrete and structural elements made from it;
• broken brick;
• foam glass;

Mineral wool

Fiber insulation. (Wood fiber)

Cinder concrete

Foam glass

Each of the above materials has a different price category, mechanical properties and density. The material should be selected taking into account the local conditions of the chimney. It is important to take into account the ease of installation, since the insulation of such structures involves working at heights, and this is not something to joke about.

• The use of flammable materials is strictly prohibited.
• It is better to choose a material that is pliable and light. Cinder blocks are used by professional builders based on a developed project with calculated loads on the roof and load-bearing structures. Self-insulation is much easier to do with mineral wool.
• Pay attention to the operating recommendations specified in the manufacturer's instructions.

Do not load the roof structure. Try to approach the matter from the point of view of the lightest possible insulating structure.

The design of an insulated chimney and its features

Insulation of chimney pipes with various materials

The figure shows an example of insulation of a chimney pipe with mineral wool and a galvanized sheet (left), and insulation with mineral wool and decorated slag concrete (right). This example is considered for a chimney made of asbestos-cement pipe.

A comparative example of how thermal insulation works is shown in the figure, as they say: “Find 10 differences.”

Protective effect of insulation

A layer of insulation material protects the structure from condensation inside and from weathering outside.

How to insulate a chimney pipe with your own hands: basic design parameters

There are several ways to insulate yourself. The difference between them is due to the material used.

For the “Rich Way” option, you can use a ready-made chimney sandwich. This product is manufactured at enterprises and combines the optimal performance and properties of an insulated chimney. All you have to do is assemble it like a construction set, based on the desired height of the structure.

Example of installation of sandwich chimneys for exterior and interior use.

Design examples

The budget option for insulation should be considered in stages. (Example for asbestos cement pipe).

Chimneys made from asbestos-cement pipes are insulated in two ways. The first involves wrapping the pipe with insulation (mineral or basalt wool), fixing it with wire and placing a casing over the insulation. The second method is implemented by lining the pipe with special slag concrete blocks and, if necessary, insulating it with mineral wool, as in the first example. This method is more labor-intensive and expensive.

1. An asbestos-cement pipe is wrapped with a 100 mm thick layer of heat insulation.

Beginning of winding with thermal insulation material

It should be taken into account that the insulation tends to shrink when it is fixed. Its minimum thickness (in a compressed state) must be at least 60 mm.

2. Fix the insulation with wire along its entire length. In this case, it is necessary to maintain the same thickness along the entire length.

Fixing the heat insulator

Do not use wire with an electrical insulating layer (wire) to fix the heat insulator. When the chimney heats up, the rubber or vinyl insulation of the wire may not withstand the high temperature and melt. Thus violating the physical properties of the insulation and its integrity.

It is better to use thin steel wire.

3. The next stage involves wrapping the insulation with a galvanized sheet.

The sheet can be used up to 1 mm thick; it is more flexible and easier to install. To determine the circumference, use a tape measure, but add 20mm to the actual measurement. This is necessary for the overlap, which will serve as a connection point with rivets or screws.

Installed casing section

If possible, roll the edges at the seam to give it an ideal circle shape.

It is better to place the section on the pipe with the seam facing inward. The appearance of this design is more aesthetic.

4. Final stage.

The final stage of insulating an asbestos chimney is installing a protective cone to prevent rainfall from entering the chimney pipe.

Completed view of an insulated chimney

This method of insulation is one of the most economical. It also provides for relatively simple installation.

No matter how simple the process of performing work at height may seem, you should not expose yourself to thoughtless risks. Therefore, all work on insulating chimneys of any design must be carried out by two people.

Another popular way to insulate an asbestos chimney is to use chimney bricks. The space between the brick and the pipe is filled with insulation (mineral wool).

Using chimney bricks

This method is more expensive due to the cost of the brick. Brickwork also weathers over time.

Chimney made of steel pipe.

Insulation of a chimney made of a steel pipe is carried out in a similar way. It should be taken into account that steel has greater thermal conductivity compared to asbestos cement, so it is better to use basalt wool. The clamp is also made of galvanized sheet steel.

Insulation of a chimney made of steel pipe

Brick chimney.

Insulation of a brick chimney is the most labor-intensive process compared to other types.

One effective way is to plaster the chimney. This method involves laying a mixture of cement, lime and slag over the entire area of ​​the outer surface. The layer thickness must be at least 30 mm.

After applying the first layer, it needs to be allowed to dry. This will help identify cracks in the applied layer and eliminate them. The subsequent layer can be applied after laying the mineral wool layer. After which another layer of plaster is applied. Subsequently, such a chimney can be whitewashed or painted. As an option, you can use facing bricks, but this makes the structure much heavier.

Fragment of insulation design

Required materials and tools

The materials required for insulation are listed in the examples discussed.

Tools required to perform insulation:

• plumbing tools (hammer, clamps, pliers, screwdrivers, etc.);
• measuring instrument (tape measure, ruler, square, level, construction pencil, felt-tip pen);
• mounting knife for cutting insulation;
• a riveter and a set of rivets for connecting a galvanized casing (or self-tapping screws);
• electric drill and portable cable extension 220 V;
• drills with a diameter of 4 mm for making holes for rivets;
• for work on applying cement mortar you will need a spatula, trowel and a container for mixing the mortar;
• You may need a construction syringe with a tube of bitumen mastic to seal small cracks. But mastic may also be needed for additional waterproofing of the plaster.

Bitumen mastic can be diluted with gasoline if it has hardened. In this case, the amount of gasoline is determined by eye. Add a little to the mastic and stir until it has a sticky consistency.

We should not forget that any method of chimney insulation is work at height.

Assess the workplace taking into account all possible risks. Try to minimize them. Prepare the ladder in advance, check its condition, reliability and stability. If you have to move on a roof with slate flooring, walk on the laid boards, this way the weight is better distributed over the area. The board should be laid across the slate waves. Check the integrity of the ropes used to lift materials and tools. If possible, secure yourself with a rope, wrapping it around your waist and securely fastening it to the supporting element of the structure. (In ideal conditions, this is the use of a mounting safety belt). Work in special clothing.

Errors leading to undesirable consequences

Sometimes, in order to save money, a pipeline is passed through the ceiling without insulation. Such actions are undesirable; insignificant savings can lead to tragic consequences.

To prevent this situation, the chimney should be insulated along its entire length.

The exception is the area in close proximity to the furnace or boiler. It is necessary to leave a section up to 500 mm long uninsulated. This will prevent overheating of the insulation, as it may lose its properties due to critical overheating. Data on the critical temperature for a particular material are indicated by its manufacturer in the operating instructions.

Experience shows that thermal insulation of furnace equipment is becoming increasingly in demand. The costs of insulation or even reconstruction of the smoke exhaust system are more than recouped due to economical heat consumption.

You may also find the following article useful for tips and instructions for cleaning chimneys: .

A wide range of materials and construction solutions allows you to use your imagination and make things more interesting.

A variety of materials are used to build a chimney in a private house, but often the owners do not care about insulating the structure. With wood-burning stoves this was not particularly necessary, but modern heating boilers release gases with completely different characteristics.

Why do you need to insulate a chimney pipe?

Harmful combustion products are removed through vertically located chimneys. The channels are destroyed over time under the influence of the atmosphere and gases passing through them. This is facilitated by the difference between the temperature inside and outside, which causes condensation to accumulate. To increase the service life and achieve optimal functioning of the structure, insulate chimney pipes from any materials with your own hands.

For comparison: this is what uninsulated structures with thermal insulation in the cladding look like

In channels not protected by insulation, the dew point shifts, that is, the place where moisture accumulates. The temperature of flue gases from a gas or pyrolysis boiler rarely exceeds 200°, while for wood-burning stoves it is within 600°. This means that the location of the dew point formation is lower, the less heated the exhaust gases are. To raise it, the pipe is insulated.

In a cold chimney, moisture settles on the walls; if brick is used, it is absorbed into it. In winter it expands and destruction begins. Soot adheres well to the damp surface, on which volatile products from fuel combustion accumulate. Among them are very aggressive acids that can destroy even metal products.

The insulated design does not require constant cleaning of soot. It doesn’t pile up inside, it burns out. The heating of the channel accelerates, and good stable traction appears even after a long break. As a result, the efficiency of using heating installations increases.

The location of the chimney influences the method of insulation.

Pipes attached to the outer wall of a building especially need thermal insulation. Still, regardless of the location, the best option is insulation along the entire length, even if most of the gas outlet is located under the roof of the house.

How to insulate the outside of a chimney?

For thermal insulation they mainly use:

• covering with tile materials;
• erection of a wooden panel frame around the structure;
• installation of an external pipe with a large diameter;
• lime-slag plaster.

Thermal insulation material with a fibrous structure is used as fillers: mineral or glass wool. Also, the space between the frame and the chimney can be filled with dry sand, expanded clay, and crushed brick.

Insulation of a brick structure with mineral wool

Limitations in the choice of thermal insulation relate to the material of the chimney. Fire safety requirements are taken into account, which must be fully complied with to prevent a fire from occurring.

Other factors are taken into account:

1. Outlet gas temperature. As it increases, a smaller layer of thermal insulation is required, but the requirements for fire protection and heat resistance of the material increase.
2. Location. Structures outside the house warm up less well, so better insulation will be needed.
3. Material. The type of thermal insulation is used depending on the possibility of installation on the structure.

Industrial sandwich pipe design

Some insulation materials do not require additional protection from external moisture and vapor barrier. These include metal cases. It is better to cover a wooden panel with weather-resistant enamel, and cinder-concrete slabs with a thin layer of plaster. Basalt wool and other similar insulation materials require mandatory protection from external influences.

It is not difficult to calculate the required amount of thermal insulation material. For a rectangular structure, all parameters are determined and the total area is found out. For a round structure, measure the circumference with a tape measure and multiply by the height. With a known area, it remains to take into account the required thickness of the insulation.

Two ways to insulate a brick chimney

Mostly plastering or mineral wool options are used. With any chosen method, they begin with cleaning the canal. If this is not done, after insulation the channels warm up faster, and the soot remaining inside begins to quickly burn out. Negative consequences occur: increased temperature, increased smoke.

Prepare the outer surface: severely damaged bricks are removed and replaced with new ones. Next, plastering is carried out under mineral wool insulation, except in the case when facing bricks were used. This ensures the same distance from the insulation to the wall, the chimney will warm up evenly. Lime-sand or cement mortar is used.

The profile is attached to hangers around the perimeter. The operation is similar to that carried out before covering the walls with plasterboard. You will need a screwdriver and self-tapping screws with plastic dowels, as well as a concrete drill of the appropriate diameter. The maximum distance between profiles should not exceed 60 cm.

Basalt wool with a thickness of at least 5 cm is placed in the space between them, which is pre-cut into pieces of the required size. It is important to achieve a tight installation so that voids do not form that will become cold bridges. Fastening to the surface is carried out with foil construction tape, pieces of wire or dowel mushrooms.

An important point that cannot be ignored is the installation of a waterproofing membrane on the outside. Otherwise, mineral wool, which absorbs water well and releases it poorly, will become damp and significantly lose its thermal insulation characteristics.

The brick pipe is insulated and sheathed with tin

The final stage is external finishing. Popular is profiled iron, which is mounted on a previously installed metal profile. This design looks beautiful and protects from the wind. A gap of 25 mm is left between the corrugated sheet and the insulation, through which moisture that gets inside is removed.

For exterior finishing, the use of other materials is allowed. The fixed basalt insulation is covered with decorative bricks, cinder blocks or asbestos-cement slabs. In the latter case, the minimum wall thickness is 40 mm.

Plaster will insulate a brick pipe

Insulating a brick chimney pipe with plaster is easier. The surface is pre-cleaned and a layer of deep penetration primer is applied. A reinforced mesh is fixed on the walls with dowels, a mortar of cement, lime with fillers made of slag or other heat-resistant materials is poured. After the first layer has dried, any cracks are repaired and a second, thinner layer is applied. The brick structure is painted over plaster to match the roof of the building.

How to properly insulate a steel chimney

When performing work, take into account that the metal heats up to 300°. Absolutely non-combustible materials are used: various types of mineral wool and fibrous insulation, slag concrete slabs. A special heat-resistant plaster mixture is also used. To perform the “sandwich” option, use a larger iron pipe, preferably made of stainless steel.

Metal structures are often installed together with heating appliances that are used periodically: a heater in a bathhouse, decorative stoves and fireplaces. An available option in this case is the application of special plaster. The method is simple and can be easily performed even by people without experience:

• a fiberglass reinforced mesh is fixed to the surface;
• the mixture purchased in the store, according to the instructions, is added to water and beaten with a mixer until a dense, homogeneous mass is obtained;
• apply a rough layer with a spatula several times with breaks for drying;
• form a finishing surface.

Creating a Sandwich Chimney

A popular and most effective way to insulate a metal structure that is constantly in use is a case made of steel pipe. A product with a larger diameter serves as protection, while a smaller one serves as a smoke exhaust. Mineral wool, broken brick, and expanded clay are placed between them. The design is completely fireproof, the winding is protected by galvanized iron or stainless steel.

The sandwich chimney is formed in several steps:

• in the roof and its ceiling, the hole is expanded so that the diameter exceeds the dimensions of the channel by 250 mm;
• the main metal pipe is insulated with basalt wool with a layer of 5 cm;
• the heat insulator is fixed with wire, which is wrapped in a circle;
• put on a steel casing, if the iron is thin, install adhesive tape, secure with tie clamps.

A steam room requires a special approach to insulating a gas outlet. The most successful option is a steel chimney exhaust of an iron pipe in a case, and galvanizing for the casing is prohibited. Increased temperature and humidity lead to the release of harmful substances. A rational option is stainless steel.

Asbestos-cement chimney - proper thermal insulation

The structure is insulated using a frame method. Before carrying out major work, the pipe is thoroughly cleaned. Further actions:

1. Galvanized sheets are used to make the protective casing. The blanks are marked with the expectation that there will be a distance of 6 cm or more between the inner and outer walls. In height, the standard galvanized width is 1 meter.
2. Install protection starting from the bottom. Each segment is densely filled with mineral wool. The sections are connected with bolts.
3. The upper part is covered with cement mortar so that the insulation does not get wet. The layer is formed with a slight outward slope so that water does not stagnate.

Insulation without sheathing is used as a temporary measure

It can often be observed that the insulation of an asbestos-cement chimney is carried out with a simple winding of mineral wool, which is fixed with ties. A similar option is allowed in the attic, and in relation to any material. Outside, such a structure will not last long: it gets wet and suffers from the wind.

Before insulation, especially of an asbestos-cement or steel chimney, make sure that the structure is installed correctly. The gas exhaust pipe must comply with fire safety rules and other technological standards.

It is recommended to use insulation that breathes and does not accumulate moisture. In other cases, ventilation gaps of at least 25 mm must be left. Use materials that are available for self-installation. Manufacturer's instructions are followed.

Among mineral insulation materials, basalt wool is the most effective. It is somewhat more expensive than the usual mineral one, but with low consumption this does not play a significant role. But in reality there are significant advantages:

• fire is possible at very high temperatures;
• has increased density;
• significant vapor permeability.

Basalt wool is good for thermal insulation both outside and in the attic

Even the highest quality thermal insulation does not extend the service life of a structure when it is not first brought to the proper condition: cleaning and replacement of damaged elements is required.

Work on external insulation of the chimney is carried out immediately after its construction. After a few years, destructive processes begin that thermal insulation can no longer stop. Repair or complete replacement of the structure will be required.