Insulation of ventilation pipes in a cold attic. Insulation of ventilation pipes and air ducts: materials and technology. Places for insulation

One of the mandatory conditions for putting an industrial premises or residential building into operation is ventilation as one of the critical systems life support. Creating a comfortable microclimate is impossible without proper arrangement the entire complex of equipment, including thermal insulation of air ducts. Let's try to determine which insulation for ventilation pipes is most effective and which areas need protection from cooling.

Why is pipe insulation necessary?

Leaving the heated room through special outlets, in unheated areas warm air masses come into contact with the cold walls of the structure, resulting in the formation of condensation. It is dangerous because over time it causes corrosion of metal parts (3-4 years are enough for galvanized iron), and in the event of a sharp drop in temperature, icing and breakage of structural fragments. In addition, an increased level of humidity in the attic provokes the emergence of mold and mildew, which spreads into the residential sector.

Reasons for appearance humid air in the attic

Drops flowing down cooled surfaces fall on the floor, accumulate and, without having time to evaporate, are absorbed into the structure of the ceilings. For water, it doesn’t matter what kind of material was used during construction; after some period it can destroy and wooden beams, And concrete slabs.

To prevent the appearance of dampness, it is necessary either to make all the rooms in which structural elements are located heated, or to insulate and vapor barrier the ventilation air ducts. The second method is easier to implement and more rational if, for example, the attic has a large area.

Protection from moisture is only one purpose of thermal insulation measures. Thick basalt mats or thin penofol are good noise absorbers, and silence is important for comfortable stay no less than dryness. Requirements for the arrangement of ventilation systems in apartment buildings regulated by SNiP (for example, SNiP 2.04.44-88), it would not be superfluous to use them when building a private house.

Self-insulation pipes in a wooden house

Materials for ventilation insulation

Installation of technical communications is a construction activity that requires a thorough approach and the use of high-quality products, the service life of which is at least 15 years. The reason lies in the practical approach: replacing the “wrapping” of a pipeline or repairing one of the structural fragments is quite difficult, especially if the breakdown occurred in an area protected by ceilings. Let's consider the characteristics of products that have good recommendations and suitable for independent arrangement insulated air ducts.

Thermal insulation with foil material

Mineral wool, glass wool, basalt wool

Prototype mineral wool is glass wool - an inexpensive fireproof product created on the basis of glass fiber. It is still actively used for reliable protection pipelines. Sample product – IsotecMat-Al, flexible roll products made from molten glass. Due to their low thermal conductivity and water-repellent properties, thin foil mats maintain the integrity of the air ducts and prevent getting wet.

Rockwool mineral wool with metallized coating

Technical characteristics of IsotecMat-Al meet the requirements of GOST:

composition – fiberglass + metal;
thickness – 50 mm;
flammability - G1 (low flammability);
density – 22 kg/m³;
thermal conductivity coefficient – 0.036 W/(m*K);
types of work - for ventilation.

Thanks to a special production technology, glass fiber receives a vertical orientation and allows the mats to be bent without the formation of creases. Unlike old analogues, modern mineral wool has minimum thickness, which is preserved when folded. If you follow the installation technology, you can create a durable, tight-fitting “cover” that prevents the formation of condensation and absorbs noise.

Soft rolls are great for protecting rounded and curved surfaces. If you purchased an inexpensive budget option, not reinforced with foil, you will have to additionally use waterproofing - the same foil or at least roofing felt. To fix the rolled fragments, use a reliable bandage made of synthetic or metallized tape; if it is not available, simply wrap it with steel wire.

Using a mat basalt wool for insulating the joint with the ceiling

For equipment rectangular shapes sometimes mineral wool mats with higher density are used. They are divided into convenient parts construction knife, glued to liquid nails, covered with foil and secured with tape.

Foam plastic, polyurethane, polystyrene foam

Three synthetic modifications are not afraid of moisture, have suitable thermal conductivity parameters and have a service life of up to 50 years. The main disadvantage is non-compliance with fire safety requirements, therefore PU foam products are not recommended for use in residential buildings(class G3). When a fire occurs, structural parts begin to melt and release compounds harmful to health.

Unlike mineral wool, expanded polystyrene has a rigid structure, therefore it is sold not in the form of slabs (as for walls or floors), but in the form of a shell - 2 or 4 segment tubes, fixed from the outside and forming a solid cocoon. The prefabricated parts are connected according to the tongue-and-groove principle and glued or wrapped with a bandage of tapes. There are reinforced foil types that are more effective.

Polystyrene foam shell for pipes

Polystyrene foam is cheaper than expanded polystyrene and has a looser structure, but this property is useful for insulating curved structures. Foam plastic is preferred by economical owners who do not see the difference between almost identical materials used in an inaccessible or hidden place (for example, in the attic).

An example of a hard shell is PPU K 1 (design No. 1) from the Far Eastern manufacturer Avangard. Specifications:

composition – polyurethane foam;
density – 60 kg/m³;
flammability - ГЗ (normally flammable);
thermal conductivity coefficient – 0.029 W/(m*K);
water absorption – 2.0%;
max operating temperature – 130 ºС.

Thanks to its synthetic composition, polyurethane foam has high biochemical stability, that is, even in the presence of dampness it does not become covered with mold or mildew.

Foamed polyethylene

The soft, elastic material, inexpensive and suitable for DIY installation, became popular immediately after it appeared on the market. In appearance it resembles foam rubber, but has a more elastic structure and does not allow moisture to pass through. The most famous representative is Penofol, the name of which has already become a household name. Thin layer Foamed polyethylene is covered with foil on one or both sides.

Despite its external lightness and minimal thickness, Penofol has all the qualities of good insulation:

retains heat perfectly;
reduces noise levels;
does not allow moisture to pass through.

Suitable for equipment ventilation structures with a complex configuration, holds well on curved areas and joints.

If you want to improve communications yourself, pay attention to self-adhesive insulation for ventilation pipes. The manufacturer Penofol also has a category that is convenient for installation - Penofol S. Rolled products made of a thin layer of polyethylene foam, covered with metal foil on one side and an adhesive layer on the other.

Technical characteristics of Penofol S:

composition – foamed polyethylene;
thickness – from 3 mm to 10 mm;
water absorption – 0.35%;
type of use – internal;
types of work - for ventilation.

There are several ways to install Penofol. If it is necessary to insulate long straight pipes, they are simply wrapped in rolled material without cutting it into fragments. Short curved sections and joints, on the contrary, are insulated in small pieces that are convenient for fastening. It is enough to cut a fragment of the required width, remove the protective film and stick it on the surface. To create a thick layer, Penofol is wrapped several times.

Rolled self-adhesive for pipe insulation

Ready-made insulated pipes - advantages of use

For those who like simplified installation, there is an offer that does not require additional thermal insulation. These are so-called sandwich pipes with a layer of factory-made insulation. The design of the products is quite simple: a protective layer of basalt fiber is inserted between two channels of different diameters.

Specifications

Insulated products are intended for the construction of chimneys and ventilation systems, and in the first case, products made of stainless steel are preferable, in the second - from galvanized steel. A mineral wool layer with the following properties is responsible for maintaining heat and protecting against moisture:

thermal conductivity coefficient – 0.038-0.051 W/(m*K);
water absorption – 2%;
strength – from 5 kPa to 80 kPa;
flammability – G1 (low flammability).

The mineral base helps preserve the structure of the fibers even after long-term use; the appearance of fungus and mold is excluded. The high melting point of the insulating liner (about 1100 ºС) makes the products fireproof, and the combined composition is durable and absorbs internal noise.

Insulated pipes for chimneys

The only disadvantage of the product is the high price compared to conventional parts, however, if you add up the cost of all materials for separate insulation and add labor costs to this, the difference in price will be noticeably reduced.

Installation features

If, by your education or occupation, you are involved in the installation of intra-house communications, then it will not be difficult for you to draw up a diagram of the ventilation system yourself. Otherwise, we recommend contacting an agency, where they will not only draw up a project, but also advise the most optimal materials.
For those who are used to building themselves, we remind you:

the wider the cross-section of the pipes, the easier the circulation of air flows (recommended minimum diameter is 140 mm);
if there are several air vents in a private house (most often this happens), they must correspond to each other in order to maintain draft balance;
short channels should not be made narrow.

Try to use the same type of pipes and thermal insulation; if natural air exchange is disrupted, consider a forced ventilation device.

Disadvantages and ways to prevent them

Insulated products do not have any disadvantages that affect the operation process. Some don't like the more substantial weight: the two layers are heavier than polymer or corrugated counterparts of the same size. However, weight does not affect the quality of installation, so this characteristic can be ignored.

If cost bothers you, make calculations: determine the difference between insulated products and a set of pipes + insulation with waterproofing (including fixing means). If the difference in amounts is small, choose the material that is easier to install.

Thematic videos

The stories will help you choose the right products and tell you how best to use them.
Tips for improving your garage:

General information about insulation:

Visual comparison of Penofol and its analogues:

So, we have examined the characteristics of the most popular insulation for ventilation ducts. Many of them are low cost and easy to use, so if you wish, you can protect your pipes from condensation yourself. If any difficulties arise, consult with specialists who will recommend a trusted brand and explain the nuances of installation.

The arrangement of various types of utilities involves the well-known ventilation pipes installed on the roof. This technique has its own special aspects and requires strict adherence to all installation processes. It is usually used in a private home. In this way, outlet channels are equipped for ventilation of premises, installation of a sewer riser, and ventilation of the attic.

How to insulate ventilation pipes on the roof, and what materials are best used for this?

Ventilation pipes on the roof should be placed in such a way that exhaust air can be removed through them without much difficulty. In this case, its height and diameter are determined based on the required productivity.

Pay attention! The simplest type of device is considered to be the pipe outlet through the roof ridge. In this case, the main condition is considered to be properly insulated to prevent the formation of condensation.

Without additional insulation moisture will accumulate on the internal sections of the pipes and flow down the walls, penetrating into all leaky places. This will cause the appearance of damp areas on the walls and ceilings and their premature destruction. And your air ducts may also suffer from condensation. To avoid all these unpleasant moments, you should take care of installing insulation around the ventilation ducts.

Which areas need to be insulated?

So, is it necessary to insulate the ventilation, and in what places does this need to be done? The answer suggests itself - insulation should be done in those places where rapid cooling of air masses occurs. Ventilation pipe laid through a solid wall, must be passed through a special heat-insulated liner and insulated right up to the deflector element. In private homes, such pipes pass through attics and are discharged outside through the roof. And their insulation is carried out from the point where noticeable cooling begins. Moreover, it is recommended to move the insulating border slightly towards the warm room. This is in case the frosts are more severe than usual.

Insulation materials

You should consider all acceptable methods of insulation and choose the most suitable one. It is important that the method we choose meets certain requirements:

Good thermal insulation properties.
Fire safety. The material should not belong to the flammable group.
Relatively low cost.

We will analyze only those options when the channels are insulated from the outside. After all, it is not always possible to dismantle the structure, and the internal diameter will be noticeably reduced due to insulation. So what is the best way to do such work?

One of known materials considered mineral wool. It is a cheap option, has 100% fire safety, and is produced in rolls with a layer thickness of five centimeters. But there are also disadvantages associated with labor-intensive work. The fact is that the cotton wool needs to be wrapped around the pipe, and a protective layer of foil or galvanized steel is placed on top. Work with such material must be carried out in protective equipment that protects the respiratory system and eyes.

During operation, the material cakes somewhat, forming gaps in the insulating layer. If moisture penetrates the insulating layer, it also loses its properties. The best solution is to use a corrugated pipe, which is based on cotton wool. But this method is good at zero point in the construction of ventilation pipes.

Using polystyrene foam as an insulating material is considered a good solution, especially if you purchased a ready-made split shell. All that remains is to put it on the pipe and connect it together at the seams. This method provides good thermal insulation, is performed quite simply and without danger to health, and is relatively cheap. However, the material is considered flammable and releases toxins when burned.

You can use shells made of polyurethane foam and polypropylene foam. Such materials are stronger than polystyrene foam and are more expensive. To work, they need a bandage made with ordinary knitting wire. The manufacturer produces such insulating structures in the form of tubes of various diameters with cuts. All that remains is to put such blanks on the pipe, and the insulation is ready. The material is cheap, able to withstand moisture and minor mechanical stress.

And another option is self-adhesive material. The method of operation is simple - remove the protective film from the adhesive side, apply it to the pipe and press it. This material is perfect for square or rectangular shafts. The layer of insulation material reaches one centimeter. If necessary, it can be used in several layers.

Remember! The effective operation of your ventilation system depends on the correct insulation.

Video

This video will help you understand what and how best to do when arranging the ventilation of a private home:

Ventilation in apartments is located in the wettest rooms, and in private houses most of the system is located in unheated areas. Increased humidity levels and the collision of warm and cold air lead to the formation of destructive condensation on the walls of the outlet. Moisture accelerates the corrosion process and also causes the appearance of fungus and mold. The ventilation system becomes a distributor of microorganism spores that can cause various types of diseases in residents. At the moment, the only way to solve this problem is to insulate the ventilation pipes in the attic, as well as in other unfavorable areas where the system is located.

Advantages of insulated ventilation

The main task of ventilation ducts is to maintain a comfortable level of temperature and humidity in the house. In addition, they are responsible for the supply of fresh air and the removal of dust-contaminated air. Protecting the channel from influence on it unfavorable factors will not only improve the quality of its work, but also significantly extend its service life. Insulated ventilation pipes have the following advantages.

Low level noise

Methods for insulating ventilation pipes

Roll materials

This group of insulation materials is universal, as it can be used both for insulating round pipes and for insulating square boxes. In addition, they are the simplest and most convenient to use. Installation begins with cleaning the outlet surface, removing rust and moisture stains. Next, a piece of rolled material is wrapped around a certain section of the channel. The number of layers is chosen at your discretion, but it is preferable to have more than one. The edge of the insulator is temporarily secured with tape.

After wrapping the entire accessible area of the system, it is necessary to protect the insulation from moisture penetration. For these purposes, a foil insulator with a thickness of about 4 mm is used, which is wrapped around the insulation in one layer. The joints of the canvases are sealed with reinforced tape, which will prevent moisture and dust from penetrating into the cracks between the joints, and will also securely fix the edges of the materials.

Foam plastic

Insulation of square boxes is carried out using sheet foam. Since this variety is better known, some people do not understand how to insulate a ventilation pipe using this material. Circular channels are insulated using special elements in the form of a shell. Two parts of one segment are connected by tongues and grooves.

Beacons are marked on the element along which cutting will be done. The length of each segment is measured based on the length of sections of the system between its turns and other things. Using a stationery knife, a segment is cut off. Two halves of the segment are applied to the cleaned surface and connected to each other by pressing firmly on their edges. It is necessary to drive the tenons into the grooves from one edge of the segment to the other.

Insulation of pipes with foam plastic

Foamed polyethylene

Installation of this insulator is also one of the easiest jobs to perform. Before fixing the insulation, the pipe is thoroughly cleaned and dried. The length between the exit of the ventilation duct from the wall, either to its entry into the opposite wall, or to its first turn, is measured. A section on a tubular insulating form is measured and cut to the appropriate length. This segment is cut along one of the sides from beginning to end. The cut is made strictly on the place intended for this purpose; on the surface of the material it looks like a seam.

We open one edge of the cut and place the mold on the pipe, gradually moving along the segment. We cover the joints between the individual segments and the places of the cuts with special glue. If desired, the glue can be replaced with adhesive mounting tape.

Foil insulation belongs to the category of more expensive materials, but their technical characteristics are superior to other options. The reflective layer allows you to reduce the thickness of the insulation

Polyurethane foam

When it is necessary to increase the level of fire resistance of the channel, the ventilation pipes are insulated with polyurethane foam. Installation of this material also begins with the process of cleaning the outlet surface from dirt, moisture and rust.

Next, the cylindrical insulation is cut into separate segments of the required sizes. Each individual segment is cut lengthwise into two equal parts. Along the edges of the semicircles, allowances are made for joining with adjacent elements. On the halves of one segment, half of the material is cut off inside the circle, on the halves of the second - on the outside of the circle. All elements are connected on the pipe, and their joining points are tightened with bandages.

Video: the process of spraying polyurethane onto a pipe

There is no urgent need to use expensive materials, as well as specific work that can only be performed by specialists.

Particular attention is paid to the arrangement of high-quality thermal insulation of external and internal surfaces of residential buildings. At the same time, thermal insulation of ventilation pipes and chimneys is carried out only in exceptional cases. Is it necessary to insulate the ventilation pipe on the roof? This question is of interest to the owners of private households, where an autonomous heating system for the house is provided, there is a chimney and forced ventilation.

Professional builders claim that as a result of reducing the thermal conductivity of chimneys and ventilation pipes, their service life is significantly increased. Carry out everything yourself construction processes related to the insulation of ventilation pipes of chimneys will not be difficult. This does not require any special knowledge or skills; you just need to choose the right quality material and put in a little effort.

The need for insulation measures

The main negative reasons affecting the service life of a brick chimney pipe are smoke or moisture. This is especially evident during the cold period, when there is a sharp change in temperature conditions.

The condensate protruding on the walls of the pipe tightly clogs all the surfaces of the brick chimney that have small cracks. The consequence of a sharp drop in temperature is the freezing of moisture and the formation of ice. As you know, water expands when it freezes, so there is pressure from the inside on construction material masonry Experiencing constant negative impact, the chimney is destroyed.

Besides this, there is another danger. The consequence of fuel combustion is a number of oxides, on their basis solutions of sulfuric or carbonic acid are obtained. Combustion waste along with condensate settles on the walls of the chimney pipe, destroying brick and metal surfaces.

Advantages of an insulated chimney:

no condensation forms on the pipe walls;
the probability of fire in the ceilings is zero;
the amount of resin and soot decreases.

Is it necessary to insulate the ventilation pipe? Definitely necessary! A structure insulated with special material looks more attractive and is easier to care for.

Choosing high-quality thermal insulation

Manufacturers offer a wide range of thermal insulation materials for ventilation pipes. Each type has certain characteristics and advantages. When choosing the most suitable thermal insulation option, the following conditions must be taken into account:

thermal insulation density;
thermal conductivity of the coating;
chimney structural material;
temperature climatic conditions;
fire safety of the material;
moisture permeability of insulation;
permissible loads, installation conditions.

Most commonly used broken brick, glass wool, fiber insulation, slag concrete slabs.

Fiberglass and mineral wool are fireproof. This quality completely eliminates the possibility of self-ignition of the material. In addition, the thermal insulation does not emit substances harmful to human life and withstands the aggressive influence of the atmospheric environment.

Various methods of thermal insulation

Today there are several options for how to insulate a pipe on the roof.

The most common method of arranging a chimney is using glass wool or mineral wool; preference should be given to materials produced in the form of slabs. During the work you should take into account high vapor permeability thermal insulation materials. Pipe insulation based on fibrous materials has a limited service life, it is necessary to equip a protective hydrocoating.

If the chimney to be insulated is made of brick, you can plaster the surfaces of the pipe. For this, a special slag-lime mixture is used. During further operation, it is necessary to regularly inspect and, if necessary, repair the plastered surfaces of the pipe. Otherwise, scalding soot can get into the formed depressions or cracks from the chimney. Floors and roofing will suffer from this. One of the main advantages of this method is the relatively low cost of insulation material and ease of installation.

How to insulate an asbestos pipe on a roof? One of the most reliable methods of thermal insulation is the use of broken brick chips or granular backfill. The created layer retains heat well and prevents the formation of condensation products. The material is inexpensive, but additional waterproofing is required. In addition, you will need to create a durable frame.

Stages of construction work

Once a suitable insulation material has been selected, you can begin work on thermal insulation of the chimney.

Attention! Any type of chimney insulation must be carried out taking into account all building codes and requirements.

When creating thermal insulation for a pipe, you should leave the necessary space (about 5 cm) between the brick chimney and the insulating material. The segment of insulation material must be laid so that it takes up about 40 cm on the roof of the attic. Care should be taken to ensure reliable tightness of all existing joints. To carry out insulation work, special adhesives with fire-resistant properties and adhesive tape are used.

High-quality insulation of the external surfaces of a brick chimney is carried out according to a certain scheme:

Upon completion of all construction work, the thermal insulation cake is decorated with facing material, which is both protection from external negative influences and an excellent decorative element.

Conclusion

It should be noted that in the absence of the necessary experience, it is better to entrust all work related to the insulation of chimneys and ventilation pipes to professionals. But if you are completely confident in your abilities, then you can carry out the insulation yourself. The main thing is to do everything carefully, do not leave gaps on the pipe, otherwise all the work will be in vain. The service life and quality of the chimney depend on the consistent and correct implementation of all processes.

Insulation is necessary to get rid of the main scourge of pipes - condensation. An uninsulated pipe is doomed to constantly become covered with moisture on the inner surface of the ventilation duct. Draining condensate will certainly seep through the joints and saturate the walls and ceilings. Consequences: damp walls and ceilings, mold, plaster collapse, etc.

The main question is: why?

It is affected depending on the material from which it is made:

will gradually lose its protective layer.
Condensation is not a problem for PVC either.

Another danger that threatens a building due to condensation in ventilation ducts is the freezing of frost outside a warm room. If frosts are severe and prolonged, only because of this phenomenon the clearance in the ventilation duct can narrow to zero.

Condensation appears for two reasons:

Saturation of the air in a living room with water vapor due to current activities: cooking, washing, and also from breathing. Household appliances during operation can also be a source of water vapor: irons, microwave ovens, humidifiers, etc.
In production, equipment can be a constant source of water vapor entering the ventilation ducts.

The amount of steam that can constantly be in the air directly depends on the temperature. The higher the air temperature, the more steam it can contain. A change in temperature, even slightly, leads to a decrease in the ability of the air to hold water in a vapor state, which is why when cooling the air, condensation necessarily settles at the outlet of the ventilation duct.

Where should insulation be done?

The answer is simple: where the temperature difference occurs. When a ventilation pipe passes through the main wall of a building, the hole is lined with thermal insulation, and the pipe itself is insulated right up to the reflector. For example, when leading a ventilation pipe from a private house through an unheated attic to the roof, it is necessary to insulate the point of passage through the ceiling of the topmost floor, and the pipe itself before it exits onto the roof.

Where the temperature of the walls of the ventilation duct changes, condensation occurs. This point is also called the “dew point”. It is from this that the insulation is installed. Calculating the position of this point is the first stage in insulation design.

The situation is somewhat different with supply ventilation. The amount of supply ventilation duct deposited on its outer walls is directly dependent on the length of the ventilation duct and the features of its installation. Here it may be necessary to insulate not only pipes, but also valves. It should be noted that insulated valves are required mainly in very spacious rooms(offices, warehouses, production workshops). Externally, it looks like adjustable blinds that can limit air flow and increase the temperature of the supplied air using tubular heaters.

It is possible to regulate the air flow rate through the valve manually using special levers, or using a simple electric drive system. A typical example of the technical characteristics of such a valve: cross-section up to 3.5 sq.m. and the power of heating heating elements is up to 8 kW. Moreover, with such a large cross-sectional area, heating elements will not be able to significantly change the temperature of the supplied air; their task is different: to heat the valve flaps in order to prevent them from icing and accidents.

In each case, when choosing a ventilation insulation option, a preliminary economic calculation is necessary. The total length of the ventilation duct and the costs of its insulation are calculated. The obtained data is also compared with the cost of ventilation repairs. By comparing the numbers, a decision is made on the feasibility of insulation.

Using the table, it is easy to determine, given the calculated indoor air temperature and a known average air humidity, where exactly the “dew point” will be located. Where the duct wall cools to the temperature indicated in the table.

How to insulate?

When there is a need for insulation, the “dew point” has been found, all the necessary calculations have been carried out, the key question remains to be resolved: what material to use for insulation? Consumers have the same requirements for modern heat-insulating materials:

High thermal insulation properties;
Fire safety;
Affordable price.

Here is a comparative analysis of the most popular heat-insulating materials today with an overview of their advantages and disadvantages:

Mineral wool. The cheapest to insulate, absolutely fireproof. Disadvantages include: labor-intensive installation, caking, the need to comply with safety measures during direct contact with the material, loss of heat-insulating properties when damp.

Polystyrene foam or polystyrene foam. Very easy to use solution. Foam plastic “shells” are available in various diameters and dimensions and are completely ready for installation. The two hemispheres are fixed using a tongue-and-groove connection. Cheapness and durability are two more important advantages. Important disadvantages limit the use of this material: flammability and toxicity of combustion products, as well as inflexibility and fragility.

Polyurethane foam and polypropylene foam. The principle of making insulation is the same as the previous one. The two plastic shells are also held together using a tongue-and-groove joint. However, the properties of this insulation are different. First of all, it has much higher mechanical strength. The cost of the material is higher than that of foam. Also, for installation, in addition to the groove connection, a wire bandage is used, which increases the cost of installation.

Foamed polyethylene. Available in the format of split pipes of different diameters. During installation, the tube is simply placed on top of the ventilation duct. That's the whole installation. Key advantages: low cost and moisture resistance, mechanical strength. Available in format penofol– foamed polyethylene with outer covering made of aluminum foil. Due to the coating, the thermal insulation capacity increases, and the system also acquires dust-repellent properties. The fastening is very simple - the surface adjacent to the ventilation duct is self-adhesive.

Conclusion

The need to insulate ventilation ducts must be economically justified, since with a large length of ventilation systems and large diameters of ventilation ducts, the costs of insulation will be serious. The choice of heat-insulating material is also carried out taking into account its characteristics and cost. We bring to your attention a video material that outlines current issues of insulating hoods.

One of the ways to insulate a ventilation pipe

Such questions arise before the owner who equips the premises with a heating and ventilation system. The answer to the first question in most regions of Russia is obvious. But how and with what help you can do this, you should figure it out.

When installing ventilation ducts, various materials are used: galvanized, polypropylene, flexible corrugated. Ventilation ducts often need to be insulated. To save on labor costs and reduce costs, you can use ready-made insulated pipes for ventilation.

Composition and technical characteristics of insulated pipes

Insulated flexible pipe for ventilation has good characteristics, but loses in appearance

Insulated channels are otherwise called sandwich pipes. They received this name because of their design: two pipes, between which insulating material. The pipes have different diameters, the difference between which is the width of the insulation layer.

Stainless steel is usually used as the material for the ventilation pipe. The outer pipe can be made of galvanized steel. Such options are often chosen for chimneys, because stainless steel is resistant to high temperatures and is generally more durable. For ventilation, it is enough to use a sandwich pipe, both components of which are made of galvanized steel. This will also allow you to save about 50% due to the cheapness of the material.

Stainless steel pipe can also be used for a chimney

Basalt fiber is often used as insulation, as it has an optimal set of characteristics:

Low degree of thermal conductivity: 0.03-0.05 V*m/K.
Water absorption: 2%. The material practically does not absorb moisture, which ensures its hydrophobic property;
Strength: 5-80 kPa. Indicators vary for different brands of material.
Long service life is ensured by strength properties and a low likelihood of deformation occurring over time. Basalt does not rot and does not contribute to the spread of fungus.
Fire safety. The non-flammable qualities of the material can become an obstacle to the movement of fire. Melting point - 1114°C.
Vapor permeability. The ability to pass steam without releasing warm air.
Soundproofing. Basalt fiber reduces vertical sound waves.

It is especially worth emphasizing the low chemical activity of basalt. When it comes into contact with metal surfaces, the risk of rust on the metal is reduced to zero.

Advantages and Disadvantages

Pros

Advantages of sandwich pipes for ventilation:

High performance and characteristics ensuring long service life and reliability of the completed ventilation ducts.
Working with insulated pipes for ventilation is quite simple. A non-professional can perform all the main stages of installation.
Laying sandwich pipes takes much less time than installing a conventional pipe and its subsequent insulation.
Attractive appearance. If you insulate ventilation pipes yourself, it is not easy to achieve aesthetics.
Longer service life. The sandwich pipe is protected from condensate penetration.

Cons

Among the disadvantages of a ready-made insulated pipe for ventilation, the higher price stands out. You can always use cheaper types of pipes and insulation, and also not make the outer shell of metal, but use any protective materials. But this option is not acceptable if the ventilation duct is located in a clearly visible place.
Another disadvantage is the large weight of the sandwich pipe. It is twice the weight of normal metal pipe and several times - polymer or corrugated channels.

Features of installation of insulated ventilation

You can install ventilation yourself, but design it should be entrusted to a specialist

To ensure optimal ventilation without forced air, all pipe laying requirements must be taken into account at the design stage.
In particular, comply with the basic rules and requirements:

Large cross-section pipe: the larger it is, the less resistance the circulating air will receive. The minimum permissible section is 14x14 cm;
Channel length. Air discharges faster with higher ducts. The shorter it is, the larger the diameter of the pipe for ventilation should be chosen.
Number and correspondence of channels. In a private house, one air circulation line is rarely enough. It is advisable to equip all channels identically, otherwise they will have different levels of thrust.
Pipe insulation. This will allow you to save it from the occurrence and harmful effects of condensation.

It is better to entrust the design of ventilation to professionals, so that the individual conditions of the house are taken into account and the following basic parameters are developed: location of channels, diameter, length and type of pipes.

At an outdoor temperature of 12°C and an indoor temperature of 20-24°C, natural circulation occurs through the ventilation ducts. If it is missing, errors were made during channel design or installation.

Do not forget that to ensure the operation of natural ventilation it is necessary to provide normal access fresh air. To do this, you need to regularly ventilate the rooms.

Some engineering communications require mandatory ventilation, which is installed on the roof. So, ventilation needs to be arranged: sewerage, room ventilation, attic ventilation, etc. Its manufacture requires compliance with a number of requirements and technological processes on installation. In particular, during work the question may arise about how to insulate a ventilation pipe in a private house and whether it is necessary at all. This is what this article will be devoted to.

Insulation of ventilation. Is it necessary?

First you need to understand whether it is necessary to insulate the ventilation pipe, which is located on the roof and attic. Here the answer is obvious, but then another question arises: why insulate it? The reason lies in condensation. If there is no insulation on the pipe, then condensation will form inside the pipe. Accordingly, it will flow down and flow into all the cracks and joints. This leads to the formation of wet spots in the ceiling or wall. And if there is severe frost outside, then the internal diameter of the pipe may decrease due to frost that has appeared.

Why is this phenomenon observed? This is explained by the fact that warm air contains a large amount of moisture. When in winter it comes into contact with cold pipe, then it cools down. As a result, condensation appears, formed from air vapor. This physical process can only be stopped by insulating the ventilation pipe.

Where should ventilation be insulated?

Based on the above, it becomes obvious that it is necessary to insulate the ventilation pipe in the place where there will be active contact of the warm air flow with the cold one. So, for example, if you have a ventilation pipe leading through the wall, then the section leading to the deflector needs insulation. Also, pipes often pass through the uninsulated attic of a private house. In this place there is also a need for pipe insulation.

It happens that a newly created ventilation system in a private house works flawlessly in the summer, pleasing with its efficiency and presentability. However, with the arrival of winter, the homeowner suddenly discovers that a small amount of ice appears on the outside of the air duct. It is not difficult to guess that this is a signal to action, otherwise after a relatively short period of time the pipe will begin to collapse. As a result, serious material resources will be required to fix the problem. And, if you react in time, then you just need to buy insulation for ventilation, which you can fix without much effort yourself.

What happens if you don’t insulate?

The appearance of frost and ice on the external surfaces of the ventilation pipe indicates that condensation is accumulating inside the duct, which can lead to:

rust on a galvanized pipe;
depressurization of the ventilation system;
reducing the area of the flow part of the air duct;
decreased quality of air exchange;
penetration of moisture into the middle of wall structures and ceilings between floors, etc.

In short, poor ventilation in winter will lead to physical wear and tear the entire building. The more significant the difference between the temperature indicators of the air flows moving through the pipes and the air outside (on the street) will be formed on the walls of the ventilation passages. Hence the positive answer to the question whether it is necessary to insulate exhaust pipe ventilation in a private house?

Solving a set of problems using insulation

The ventilation “set” includes a list of equipment for pumping and removing air flows that maintain the desired microclimate characteristics indoors. This also includes air ducts: transport air “arteries” passing from the street and indoors.

In order for air channels to have the required strength and permeability, they require proper insulation. For this purpose, standards are adopted that ensure sanitary and epidemiological stability in residential buildings. Don't neglect the requirements building regulations and standards regarding heating, organization of ventilation and air conditioning of premises, as well as the use of thermal insulation and protection of buildings from heat loss.

Insulation of ventilation in a private house solves the following problems in a complex:

does not allow moisture falling from the air to settle on the surfaces of ventilation structures;
increases the resistance of structures to fire;
helps reduce heat loss;
“quenches” high generating frequencies of sound and vibration vibrations.

Criteria for choosing insulation for ventilation insulation

You need to know what and how to insulate ventilation pipes. Advantage in selection is given to the indicator thermal resistance material. The main role of the insulation is to bring the temperature on the surface of the pipe as close as possible to the amount of air leaving it. In this way, condensation can be avoided. For these purposes, materials based on mineral fiber (stone and mineral wool, fiberglass), foam elastomers, as well as polyacrylates are used: polystyrene - a product of the polymerization of styrene, polyurethane, etc.

Insulation based on metal and glass filaments obtained from inorganic components is supplied to the retail chain in the form of slabs or rigid (semi-rigid) roll materials. The choice is simplified by a wide range of insulation materials with different densities, prices and thermal insulation characteristics. The undeniable advantage of mineral wool insulation is its resistance to rotting and fire resistance.

Attention! If you don’t know how to insulate a ventilation pipe in the attic, especially if it is not heated, use special sections of mineral wool for external cladding specifically for pipes. At the same time, the inner surfaces of the hoses are insulated with fiberglass treated with a special impregnation.

Arguments for internal and external insulation

Insulated pipes for ventilation are either internal lining or external insulation. Each method is characterized differently.

Interior finishing:

It is more difficult to carry out work inside the air duct, but the insulation itself is protected from external temperature and mechanical influences;
laying the layer inside will lead to a reduction in the useful working cross-section of the air duct, which requires preliminary work to increase it;
the interior decoration must be sealed and vapor-tight so as not to absorb moisture from the air;
the surface of the insulation should not be rough so as not to interfere with the movement of air through the pipe.

It is easier to install external pipe protection, but also only in a vapor-tight design. At the same time, it is necessary to consider how to insulate the exhaust ventilation pipe rising above the living space, and what kind of water barrier to construct. The outer protective shell must protect exhaust structures from mechanical damage. An important requirement for insulation is non-flammability, because When there is an open fire and contact with air oxygen, the degree of ignition of the insulation increases significantly. External insulation does not affect the size of the internal cross-section of the ventilation duct and does not require its expansion. And pathogenic organisms (viruses, bacteria), which often occupy the inside of the walls of air ducts and, being insulated, are protected from unfavorable conditions, do not take root in the insulation layer on the outside.

Insulation of pipes: work procedure

When insulating ventilation with polystyrene foam shells, the following is carried out:

clarification of the dimensions of the ventilation pipe, in particular the internal diameter;
making cuts with a knife (or a saw);
covering the pipe cylinder (shell) with fragments, displacing them by a couple of centimeters;
closing with force the tongue-and-groove locking joint of the parts on the sides.

The structure (shell) is easy to install and dismantle in case of work on the pipe.

Work on insulation with foamed polyethylene in the form of a finished shell of a ventilation pipe comes down to the following:

taking the necessary measurements of the pipe: so that the insulation fits tightly onto the surface of the air duct;
finding a special seam on the capsule and separating it along this seam;
fixing the shell on the insulated pipe;
insulating joints and seams with adhesive or tape.

Protection made from fire-resistant polypropylene or polyurethane foam is performed as follows:

dimensions are determined;
Semi-cylindrical sections are cut from a solid workpiece with a reserve for the covering layer;
a capsule is formed from cut fragments around the pipe;
the resulting joints are hermetically fastened with bandages.

If the ventilation opening in the house is in the shape of a rectangle:

select the required thickness of roll or slab insulation (for example, basalt fiber);
cut and cut to size into fragments that are convenient to arrange for cladding;
with the help of pre-calcined steel wire, the pieces are held together;
the seams are hermetically sealed with strips of foil with an adhesive layer applied to it.

Thermal insulation for ventilation using any of these methods, despite all the positive aspects, has one weak point - “cold bridges”. It is important to prevent violations of the work technology and the prerequisites for their formation during the installation process. To do this, the joints between ventilation ducts and house structures are especially carefully insulated, otherwise the expected effect of insulation will be reduced.

Which is installed on the roof. So, ventilation needs to be arranged: sewerage, room ventilation, attic ventilation, etc. Its manufacture requires compliance with a number of requirements and installation processes. In particular, during work the question may arise about how to insulate a ventilation pipe in a private house and whether it is necessary at all. This is what this article will be devoted to.

Insulation of ventilation. Is it necessary?

Why is this phenomenon observed? This is explained by the fact that warm air contains a large amount of moisture. When it comes into contact with a cold pipe in winter, it cools down. As a result, condensation appears, formed from air vapor. This physical process can only be stopped by insulating the ventilation pipe.

In office or production premises equipped with insulated ventilation valve. This device works on the principle of blinds, opening and closing air flows. In such a system it is possible to heat the exhaust air. For this purpose, the valve flaps are heated by a special heating element, due to which the likelihood of condensation is reduced to a minimum.

This method is very expensive, so not everyone can afford to purchase an insulated ventilation valve. Therefore, you will need to find the temperature dew point, i.e. the place where condensation begins to appear.

Below you can see a table that shows how to find where condensation appears:

How to insulate a ventilation pipe

So, it is necessary to insulate the ventilation pipe in an unheated attic. Now let's look at possible materials that can be used for this purpose. First you need to decide what requirements the selected insulation must meet:

High thermal insulation characteristics.
The material used must be fireproof.
Affordable price.

Unlike all other insulation materials, mineral wool will cost you the least. Plus, it is completely fireproof. But, despite this, the insulation has a number of negative aspects that are important to consider:

Difficult installation. The insulation process is quite labor-intensive. First of all, the pipe is wrapped with cotton wool. Next, the second layer is foil or galvanized. Finally, the structure must be tightened with a bandage.
Harmful to eyes and breathing. When working with mineral wool, you must equip yourself with protective equipment.
After a while, the cotton wool cakes. This leads to the appearance of gaps between the pipe and the insulation.
As the humidity level increases, the material loses its thermal insulation qualities.

There is another option using ready-made insulated corrugation, which has 2 layers of aluminum foil sleeve and reinforced steel wire. But for its implementation, ventilation is made from scratch.

Foam plastic

In this case, we mean a ready-made split shell made of polystyrene foam. Unlike mineral wool, it is more convenient to use. But let's take a look at the pros and cons.

Advantages of dense foam shells:

Simple installation method. The design has a tongue-and-groove connection. The two halves are placed on the pipe and pressed together, forming a tight connection.
Material provides good thermal insulation. Regardless of changes in humidity levels, it does not lose its characteristics.
Affordable price.

The main disadvantage of polystyrene foam is its flammability.

When burning, foam releases toxic fumes. Moreover, it will be problematic to use the shell on frequent turns; it is more convenient for it to work on straight sections of the ventilation pipe.

Polyurethane foam and polypropylene foam

This material is similar in appearance to a shell made of dense foam. It’s just that it is made from polyurethane foam or polypropylene foam. What's the difference?

They have a high price.
Mechanical strength is much higher.
During installation it is necessary to use a bandage. Typically, a binding wire is used in this role.

This insulation comes in the form of cut tubes of different sizes and diameters. The installation process of foamed polyethylene is very simple - the material is put on the pipe. Its advantages include:

Not afraid of high humidity.
Resistant to mechanical stress.
The structure of the insulation does not allow rodents to get in.

If you live primarily in a cold climate, then pay attention to other features of this material:

Penofol (analogue of polyethylene foam with a layer of aluminum foil). This insulation prevents the accumulation of dust and other contaminants.
Self-adhesive insulation (made from polyethylene foam). The presence of a sticky base greatly simplifies its installation. To do this, delete protective film and press the insulation onto the surface of the pipe. If necessary, it can be glued in several layers.

So, this article examined the features of insulating a ventilation pipe on the roof. You also learned about possible options performing this work with various types of insulation. Now the choice is yours. But at the same time, be sure to take into account the requirements for insulation of the ventilation pipe. We and our readers will be interested to know what kind of insulation you used for the ventilation pipe. Leave your comments at the end of this article.