Thermal insulation materials for furnaces with a temperature of 1400. How to insulate a wooden wall from a steel furnace? General rules for installing thermal insulation of a fireplace insert

Installing a fireplace indoors and organizing it efficiently and safe work is not limited to just the construction of the foundation, frame and chimney. To complete all the work yourself, you need to apply knowledge of several branches of physics, including thermal phenomena. One of the most important stages construction is the thermal insulation of the fireplace, this is a set of measures to ensure the protection of the surface from heat leakage. Several fireplace blocks are insulated at once: the firebox, the body and the chimney.

Fireplace design drawing

Why is thermal insulation needed?

Role of warmth insulating material is that due to its poor thermal conductivity, the transfer of energy through a layer of material is difficult. Thus, you can not only preserve the heat that the fireplace produces, but also protect the structural elements of the house from high temperatures.

Chimney insulation serves several purposes.

At the external location of the pipe, intense heat exchange occurs with the cold air of the street space. A huge part of the amount of heat is released into the atmosphere, but could be used to heat the room. If you reduce this share, you will achieve higher efficiency indicators. The solution to this issue will be insulation, which is applied on top of the walls of the chimney.
Combustion products that are thrown out through the chimney contain carbon dioxide and water vapor. The temperature of all this gas exceeds a hundred degrees. Upon contact with cooled external environment the walls of the chimney form condensation on the surface of the latter. Acids, which are a combustion product, are mixed into it. The result is a chemically active environment, leading to the destruction of the walls. The appearance of condensation can only be avoided by increasing the temperature of the pipe itself, that is, by providing it with high-quality insulation.
In places where the chimney pipe passes through the ceiling or roof, contact of materials necessarily occurs. In the case of wooden buildings, this situation is a fire hazard. But additional function insulation will be to protect the ceiling surfaces.

Corner placement option

Internal insulation of fireplaces involves the localization of energy inside the firebox for the purpose of its directed transmission. The fireplace should not emit heat in all directions, especially if it is installed near a wall. It should warm those sitting directly in front of the fireplace. Special reflectors for fireplaces are installed inside the firebox and serve as a screen from infrared radiation. As a result, all the heat escapes through the combustion hole into the room.

Reliable thermal insulation for stoves and fireplaces means protecting the walls of the building from the negative effects of temperature. When the fireplace is located close to the wall, a heat-protective layer is installed, since high temperatures can lead to destruction brickwork walls or fire if the building is wooden.

What material is used

All building materials that provide insulation and are suitable for use in a fireplace can be divided into separate groups. These include stone fibers and silica, superisol, mineralite, gypsum fiber, supersil and vermiculite.

Stone fibers are obtained by pressing crumbs of gabbrodolerite and limestone. Received fibrous structure molded into slabs. One side of the plate is covered with foil, which is capable of reflecting radiation, because this type of heat propagation accounts for about half of the total energy. Such foil can withstand temperatures of several thousand degrees. This material quite durable and moisture resistant. Able to provide all possible assistance in maintaining the integrity of the structure in the event of a fire. The most popular fiber brands: PAROC FPS 17, TECHNO T80, Rockwool.

Rockwool brand insulation

The technology for using silica involves melting alumina and quartz sand. The resulting glassy mass is blown into fiber form. Fiber is already a heat-insulating material, but for ease of use it is produced in the form of slabs or rolls. This substance is flexible, which makes it easy to insulate surfaces that are not perfectly flat.
Products based on calcium silicate have good thermal insulation properties. Superizol is one of the representatives of this class. Its porous structure not only improves specifications, but also facilitates easy processing. Super-insulated slabs are used to insulate fireplace casings and chimneys. They are mounted with glue or self-tapping screws. The operating temperature of the material should not exceed 1200 °C degrees.
Vermiculite slabs represent a pressed grain structure of the substance. This is a fairly rigid structure, thanks to which the surface of the slab is ready for decoration. They have a relatively high density, but are easy to saw and process. Characterized by their durability. Buyers show increased interest for the Thermax, GRENAR-ISOL and Scamol brands.

Panels made of fire-resistant material Superizol

Thermal insulation not only improves the efficiency of the fireplace, but also provides fire protection. It is important that the material remains safe for humans when heated. The requirements for building insulating materials are: technical indicators, environmental friendliness and ease of processing.

Supersil is a flexible material. It comes in the form of a silica fabric with a foil-like layer. But such production is expensive in terms of cost, which affects the final price of fabric rolls.
Gypsum fiber sheets are produced by mixing cellulose with gypsum and then pressing them. Distinctive feature The advantage of such sheets is that they can be used as a building material. Gypsum fiber does not tolerate deformation, therefore it is used only for insulating the fireplace body, walls and floor.

Carrying out work

The technology for thermal insulation of a fireplace is step-by-step solution some tasks.

Setting tasks and solving them

Calculation in progress required quantity material. For more rational use Take into account the cutting and processing ability of the insulation boards or fabric.
If the fireplace is located at a distance not exceeding 50 cm from the wall, then sheets of insulating fiber are attached to its walls.
The degree of insulation can be increased using a multilayer structure.
The chimney is insulated, regardless of what material it is made of.

The characteristics of modern insulating materials will help answer the question, how to properly insulate a fireplace? To insulate walls, it is advisable to use slabs, one side of which is covered with foil. The foil creates a protective screen, and the effectiveness of such protection is quite high. Negative quality is the unaesthetic appearance of slabs made of insulating material.

IN wooden buildings It is recommended to perform insulation in several layers. To do this, a lathing is made from metal slats, where gypsum fiber boards are inserted. A wooden sheathing is mounted on top to secure sheets of fire-resistant plasterboard. The outside surface must be finished with tiles or artificial stone.

Several technologies are used to perform chimney thermal insulation. One of them is making a sandwich pipe. A box is made of metal, which has a larger diameter compared to the diameter of the chimney pipe. Mineral wool is laid along the walls of the box. Then a pipe of smaller diameter is inserted inside. When manufacturing the structure, it is necessary to provide for the option of wrapping the pipe in parts.

The brick pipe is insulated with plaster, which is applied in several layers on all sides. After the fourth layer, the outside of the pipe is lined with mineral wool slabs. They are fastened with self-tapping screws with large washers. The outside must be made of brick; it will give an aesthetic appearance to the pipe and protect the material from precipitation.

Modern fireplaces - with factory fireboxes, surround and chimney kits - are less susceptible to " human factor” than traditional brick structures, built entirely by hand.

But also finished products There is a weak point - installation, especially issues related to the thermal insulation of the firebox, on which the performance of the fireplace and the safety of the home directly depend.

Materials for thermal insulation of fireplace inserts

Some “craftsmen” use it as the main, and sometimes the only material for thermal insulation of the fireplace - even in wooden houses- cheap mineral wool and mineralite.

However, the first begins to collapse when the firebox operates at peak power, the second allows a lot of heat to pass through, which leads to charring and, if measures are not taken, to fire adjacent to the fireplace wooden partitions and walls.

Professional installers use the following insulation materials:

Calcium silicate slabs(popular brands are SilCa and Super Isol, also known as Scamotec). The material is attractive due to its light weight combined with strength and fire resistance. The slabs do not deform from heat and cold (t from -200 to +1100 °C), and are not afraid of moisture. Ideal for covering walls behind the firebox and for creating fireplace mantels, including complex shapes.
Gypsum fiber sheets(Knauf). GVL are characterized by increased hardness and strength. Used for the construction of protective false walls and simple-shaped fireplace mantles.
Basalt wool(Knauf, Paroc, Rockwool). This quality cotton wool, which does not bake and does not sag over time. Operating temperature - up to 750 °C.
Silica wool(Supersil) - a more fire resistant alternative basalt wool. The material does not contain a binder, the “weak link” of other mineral wool insulation materials, so silica wool can withstand temperatures up to 1200 °C.

You can line the firebox with brick or stone the old-fashioned way. But such structures are heavy and create additional load on the floors. Of the new materials, calcium silicate is the most interesting.

The slabs can be plastered, painted, faced with ceramics and “wild” stone.

General rules installation of thermal insulation of the fireplace insert

There must be a gap of at least 5 cm between the fireplace insert and the insulation for unhindered air circulation. Also in the thermal insulation structure you need ventilation ducts, through which heated air will enter the room.
Heat-resistant glue is needed to hold the materials together. Plates can also be connected with metal screws. Seal seams and joints: between slabs - with hot-melt adhesive or fire-resistant mastic, between sections of mineral wool seals - with fire-resistant foil tape.

The rest depends on the characteristics of the building, the fireplace insert model, and the type of cladding. Universal instructions for installation - as well as universal material- No. Therefore, it is better for non-specialists to contact experienced installers who will inspect the house, make measurements and calculations, and then offer materials and a thermal insulation scheme.

Fireplace fireplace in the house it is not only part of the decor, giving the entire home an additional touch of comfort, but a good source of heat during the cold season. Therefore, in order for his work to be most effective and at the same time comply with all necessary measures against fire safety, a fireplace in the house must not only be installed correctly, but also completed thermal insulation.

All fireplaces, regardless of the manner of execution and design, have almost the same design. First of all, this is a U-shaped portal, which has a mantelpiece and is more of a decorative part, emphasizing appearance. Then the firebox, in which direct combustion occurs. Most often they are purchased ready-made, but some owners prefer open ones. own production. The design of the fireplace also includes a chimney, through which harmful combustion products are removed, and a decompression chamber.

Since the fireplace is a source of high heat, it should be remembered that the materials used in its construction are thermal insulation, must have sufficient heat resistance, be non-flammable and have a long service life under conditions of large temperature differences. Ideal material For this purpose, stone wool is used, which today is presented on the building materials market from various manufacturing companies. Usually for fireplace insulation stone wool with a density of at least 100 kg/m³ is used.

It is produced in the form of plates with aluminum foil applied to one side.

Despite the fact that the function stone wool consists of thermal insulation; its incorrect installation can nullify all the work. For example, if the fireplace is installed near external wall premises, then the thermal insulation layer will allow it to heat the room and not the street. When placing a fireplace near the interior ceiling, a layer of heat insulator will protect the wall from overheating.

Before you start installation work, you should accurately calculate the number of required slabs and, if necessary, cut them to size. This will save time in the future and minimize the cost of necessary materials.

Direct installation of stone wool slabs is carried out using a special adhesive that is resistant to high temperatures. The slabs should be placed with foil inside the box. The boards should be tightly fitted to each other, after which the gaps should be closed with self-adhesive aluminum tape.

It's important to know that thermal insulation the layer must also be performed on existing stone or wooden elements boxes, this will further preserve their integrity during the operation of the fireplace.

Once the box is insulated, you can begin installing the firebox. It should be remembered that the space between it and the wall must have good ventilation, so you should leave a gap of about five centimeters, after which you need to install the plates also between the metal guides.

Fireplace top protection

Upon completion of work on thermal insulation After installing the firebox, you can begin arranging the upper part of the fireplace. First of all from metal profiles a rack is made into which stone wool slabs are placed. Then the entire structure is usually covered with plasterboard slabs.

To avoid unwanted heat loss, as well as to improve fire safety at the intersection of the chimney pipe ceiling A decompression chamber should be installed in the upper part of the box. To do this, simply place the stone wool slab horizontally. To improve circulation warm air through the chamber, two ventilation grilles should be installed in its wall.

Organization of chimney insulation

In all combustion products, and with them some of the hot air, the temperature of which can reach 500 degrees, is removed from the firebox through the chimney, which means it also needs to be properly insulated using stone wool.

Another option thermal insulation consists of placing the chimney pipe in a metal casing with an asbestos-cement lining and mineral wool insulation. The place where the pipe exits to the roof must also be additionally waterproofed, protecting the junction and attic space from exposure to precipitation. If the chimney is made of brick, then it should be thermally insulated using stone wool.

Application modern materials during the construction of a fireplace in the future will significantly increase its efficiency. In this case, it is necessary to strictly follow the rules fire safety during operation of the fireplace, monitoring the presence of draft and controlling the source of fire. This condition must be strictly observed for both fireplaces with open and closed fireboxes.

Video: Installation of a heat insulator in a fireplace

The use of thermal insulation materials for furnaces has several purposes: provide fire safety and reduce heat loss. The last option is most often used in the construction of fireplaces, since in this case it is necessary to create a directed flow of heat, and not to warm up the entire stove mass. During work recommended to use existing standards to avoid mistakes and prevent the risk of fire in building structures.

Special thermal insulation for fireplaces is used to minimize heat loss in all parts of the fireplace: the chimney, the stove mass and the firebox itself. This allows you to increase the coefficient useful action heating equipment. Insulation different parts fireplace has the following purposes:

Protects the chimney from the destructive effects of condensation that forms during a sudden change in temperature. The aggressive effect of condensate is due to the moisture content, various acids formed during combustion and carbon dioxide.
Where the pipe passes through the ceiling, special care should be taken to comply with fire safety standards. If wooden building materials are used, special care should be taken when protecting the ceiling surface.
High-temperature insulation in fireplaces is used to create a directed flow of thermal energy to warm people sitting across from it. For these purposes, infrared reflectors are used, which are installed in the firebox itself.
Protection wall structures using a heat-protective layer. Otherwise brick wall can quickly become unusable from a sharp temperature change, and the wood will catch fire.

The building materials used for thermal insulation of the fireplace are represented by the following groups:

containing stone fibers (Rockwool, TEXHO T80, PAROC FPS 17) – are produced in the form of slabs and have a foil coating on one of their sides, which allows them to withstand temperatures of several thousand degrees;
based on silica obtained from quartz sand and alumina, produced in the form of flexible plates;
Superizol - is made using calcium silicate and has good thermal insulation qualities, suitable for insulating fireplace bodies and their chimneys, attached with glue or self-tapping screws;
Vermiculite – presented in the form of slabs (Scamol, Thermax), consists of compressed grains of the substance, is rigid, easy to saw, and has a surface suitable for finishing;
Supersil - is a fabric made of silica with a layer of foil, has a high cost;
gypsum fiber - obtained by mixing and pressing gypsum and cellulose, suitable only for insulating solid fireplaces, floors and walls, does not withstand loads and is deformed.

When choosing materials, it is important to make sure that they are environmentally friendly so that they do not emit environment toxic substances when heated.

Fireproof wall coverings

To prevent spontaneous combustion of the walls adjacent to the furnaces, it is necessary to install special cladding made of non-combustible materials with thermal insulation properties.

Thermal insulation for furnaces in this case is carried out in two ways:

For cladding, materials are used that have reflective properties and are resistant to high temperatures.
The heat-insulating furnace casing is covered with a lining of heat-resistant tiles.

Good reflective qualities are shown by metal sheets covering non-flammable heat-insulating sheets. It is best to use stainless steel, since galvanized steel releases toxic substances when heated.

The following materials are used as thermal insulation:

basalt cardboard;
basalt wool;
minerite;
asbestos cardboard.

In accordance with SNiP 41-01-2003, installation of the casing is carried out in the following sequence:

Installation of insulation with a ventilation gap of 2 to 3 cm. The thickness of the insulating material is no more than 2 cm and no less than 1 cm.
Installation of metal sheet.
Maintain a distance between the stove and the casing of at least 38 cm.

Ceramic bushings are used to attach materials to the wall: they allow the required gap to be maintained and are resistant to fire. If it is not possible to maintain the specified distance between the stove and the casing, then two layers of thermal insulation sheets should be used. For example, two sheets of mineralite are attached using ceramic bushings. The distance between them is 2-3 cm. The outer sheet is covered with stainless steel.

The design of a room or bathhouse does not always allow the installation of metal cladding. Often it will not fit into the interior of the room. In this case, you can resort to sheathing with heat-resistant tiles, which are attached using a special adhesive that is resistant to high temperatures. Let's list suitable materials for cladding:

terracotta tiles;
porcelain stoneware;
tiles;
clinker tiles;
Soapstone chlorite

When installing, follow the following rules:

The ventilation gap between the wall and the fireproof sheet should be 2-3 cm.
Fire-resistant tiles are attached to the installed sheet using special adhesive mixtures.
The oven should be located no closer than 15 cm from the surface of the tile.

The following are suitable sheet fire-resistant materials for cladding with cladding:

minerite;
fireproof plasterboard containing fiberglass;
glass-magnesium sheet.

The cladding will help not only to complement the design of the room and maintain a unified style, but also to reduce the permissible distance between the stove and the wall.

Protective screens for furnaces

The thermal insulation material used for stoves must not only prevent the possibility of fire, but also protect people from too harsh infrared radiation. For these purposes, protective screens for fireplaces, as well as for sauna stoves. They can be made of metal or using brick or decorative stone.

The peculiarity of fireplace screens is that they are made exclusively of metal and can be built-in or mobile. Such designs prevent sparks and hot coals from entering the room, and also, when heated, contribute to the rapid and uniform heating of the air in the room. You can purchase a protective fence or make it yourself. Let's take a closer look at the features protective screens ovens.

Along with insulation, the furnace is insulated using bricks. There are two options: constructing a protective wall and lining the furnace with bricks. In both cases, the brick is laid using an adhesive mixture or clay. Usage cement mortar is considered as an extreme case. When lining the stove with bricks, it is necessary to provide a gap of 3 to 10 cm, as well as ventilation holes from below and from above to ensure better convection and quick heating of the room.

If you decide to build a protective wall, you should remember that the masonry is half a brick thick (120 mm); the height of the wall should be slightly higher than the stove itself. Thanks to this structure, a uniform and soft heat is created in the bathhouse, which eliminates the need for continuous heating and allows you to steam for several hours.

Stainless steel casing

Thermal insulation of the furnace using stainless steel casing has several options. By orientation in space they distinguish front and side screens. Recommended distance from oven to screen – from 1 to 5 cm. Thanks to such structures, it is possible to reduce the intensity of thermal radiation metal furnace, since the outer surface of the protective screens warms up to 1000 C. In this case, you can reduce the distance from the stove to the wall to half a meter. Ease of installation and the presence of special legs that allow you to securely fasten the screens make their use especially attractive.

For finishing walls under a boiler

If the walls of the boiler room are wooden, then they need to be pre-treated with fire retardants. The wall behind the boiler must be covered with sheet metal. The remaining area is finished with sheets of plasterboard or glass-magnesium. Then the surface is plastered or covered with ceramic tiles.

Basalt with cladding

Facing basalt slabs look aesthetically pleasing and provide good protection from fire. In addition, this material gives off heat for a long time after heating. You can use this material to cover both a brick screen and the wall itself on top of insulating sheets.

Fire safety cannot be treated negligently - the consequences of carelessness can be tragic. Modern market building materials allows you to choose an option according to your means and taste, while ensuring reliable protection from fire.

Thermal insulation of a furnace is actually a much more important process than it might seem at first glance. Unfortunately, many owners of private houses neglect stove insulation, considering it an unnecessary measure. In this article we will look at the reasons why stoves are insulated and methods of insulation.

Why insulate the stove?

In the furnace structure the following must be insulated:

Chimney.

Thermal insulation for chimney important for several reasons:

Insulation can prevent the chimney from cooling quickly, as a result of which the heat in your home will remain warm for a longer time.
A layer of insulation prevents heating of household structures.
Condensate accumulates in uninsulated pipelines, which is not just dampness, but a very aggressive substance. The fact is that during the combustion process, moisture and acids are released from the fuel, which mix and settle on the walls of the pipeline, leading to slow destruction of not only heating system, but also structural elements building.

Those walls of the stove that are located in close proximity to the wall of the house. Thermal insulation of the wall from the stove is also a very important process, since the heat of the stove leads to cracking brick walls with their subsequent destruction. In block or wooden houses, the stove must also be insulated from the walls by laying insulation.

We produce stove insulation

Insulation methods depend on several factors. For example, if we talk about a chimney, then everything depends on the material and design features. Let's consider modern methods insulation of furnace structures.

Thermal insulation between the wall and the stove

Many home craftsmen are interested in thermal insulation of the stove from the wall. And even though the insulation of the stove is neglected at first, over time the effects of the stove’s heat on the adjacent wall become clear. And the only way to protect a wall from destruction is thermal insulation.

There are several options for this:

Perhaps the simplest method, which is distinguished by its low price and ease of execution.

Lay asbestos boards on the wall.
Place foil on top of the plates, thus creating a reflector.

Advice! This method applicable when the stove is at a significant distance from the wall (50 cm or more). If the distance is less, then asbestos cannot be used, since when overheated it releases harmful substances.

Naturally, many will not like this method also for the reason that the foil wall does not have a very aesthetic appearance.

The next method is more complex, but much more effective. The instructions include the following steps:

Attach metal hangers to the wall for vertical sheathing.
Should be attached to the hangers wooden slats, which should be 2-3 cm wider than the insulation boards.
We lay mineral wool slabs between the slats.
A reflector is nailed to the slats on top of the mineral wool.

Advice! Since mineral wool is afraid of water, it is advisable to use not ordinary foil, but a material that has waterproofing properties, for example, penofol.

We mount heat-resistant hot-rolled sheets onto the reflector.
Any heat-resistant material can be mounted on top of drywall. facing material: mosaic, tile, stone, etc.

This creates reliable thermal insulation for the stove, as a result of which the wall will no longer heat up.

Thermal insulation of chimney

Thermal insulation of the chimney can be done various materials, namely:

- one of the most popular materials these days. Has a number of unique positive characteristics, but is afraid of moisture, which is why a waterproofing layer is necessary when laying mineral wool.
Glassy. Has properties similar to mineral wool.
Brick. Whole or crushed brick very often used as insulation.
Slag slabs or mortar.

These are the most acceptable thermal insulation materials for furnaces that provide truly high level insulation.

As mentioned above, the insulation of a chimney depends on the material from which the pipe is made.

Asbestos cement chimney.

We clean the surface of the pipe from dirt and dust.
We place the mineral wool in a steel casing that will be placed on the pipe. Such a casing can be made of roofing or galvanized iron. It consists of several parts, each of which does not exceed 1.5 meters in length, which makes compacting the insulating material easier.

Advice! The diameter of the casing should be 12 cm larger diameter pipes.

We put the first part of the casing on the chimney, evenly distributing the insulation.

We put on the second part. The gaps between the two parts of the casing should be no more than 100 mm.
We insulate the resulting structure to the very top.
The upper part of the pipe is installed with a slight slope.
If there is any free space left between the chimney and the casing, it should be sealed with cement mortar.

Steel chimney. Modern steel chimneys are structures made of two pipes with different diameters. In this case, the smaller pipe is the chimney, on which a protective casing is placed. A thermal insulation layer is laid between the pipes.

The smaller diameter pipe should be inserted into the larger diameter pipe.
The space created between the two pipes must be filled with mineral or stone wool.

Brick chimney. Thermal insulation for fireplaces and stoves, chimneys which are made of brick, can be produced in several ways:

Plastering method.
- We attach a reinforced mesh to the pipe.
- Prepare a slag-lime solution. To do this, we use fine slag, lime and a small amount of cement.
- Apply the first layer of plaster to the chimney, 3-4 cm thick.
- Next, you should wait a while until the plaster dries.
- We apply the following layers, the thickness of which should be 5-7 cm. Ideally, it is enough to apply 3-4 layers.

Advice! For the first layer, the consistency of the solution should be more liquid than for subsequent layers.

We whiten the pipe with lime or chalk paint.

This method allows you to reduce heat loss by an average of a quarter.

Product of a complex . A more complex, but also more effective approach.
- Cut mineral wool to the size of the chimney.
- Secure the heat insulator to the pipe using metal tape or wire. Studs with washers are also suitable for fixation.
- Line the chimney with asbestos-cement slabs or bricks. The thickness of the facing slabs must be at least 4 centimeters.
- Plaster the surface.

This method of lining chimney pipes allows you to:

Reduce heat loss by half.
Increase the density of the chimney.
Prevent the formation of condensation and, accordingly, the destruction of the chimney.
Increase the level of safety when using heating systems.

Conclusion

As you can see, thermal insulation of stoves is simply necessary. Especially if the oven is high temperature. Therefore, in production, thermal insulation of vacuum furnaces is carried out. In domestic conditions, you can carry out all the insulation work yourself.

In the video presented in this article you will find Additional information on this topic.