Do I need to insulate the duct, and how and with what is it done? How to insulate ventilation pipes in the attic? Insulation of ventilation pipes

Insulation of ventilation pipes in the attic in a private house is necessary, first of all, to prevent the formation of condensate on the surface of the channel. If condensation is allowed to appear, the liquid will begin to flow down the walls, penetrating through the joints in the ceilings and walls. As a result, the walls and ceiling will always be damp, mold will appear on them, and structural materials will be destroyed.

If the ventilation duct is made of galvanized steel, corrosion processes will develop. Also in the winter season, due to condensation processes, icing of internal surfaces occurs, as a result of which the clearance in the pipes may be reduced or even disappear.

Condensation occurs due to two factors:

Human life activity - the use of water for domestic purposes (cooking, washing, washing dishes), people's breathing.
relative humidity. When the temperature drops, excess moisture condenses in cold places, i.e. on the surfaces of the ventilation duct.

In industrial premises, forced air ventilation is often used to get rid of harmful substances in the air. High-power systems result in increased process noise.

Therefore, in industrial premises, thermal insulation of ventilation not only prevents the formation of condensate, but also improves sound insulation.

Places for warming

There are two answers to the question of where to insulate the ventilation system.

Simple answer

The solution lies in the insulation of those areas where there is a risk of sudden cooling of the air. Warming options:

The pipe is dressed in a heat-insulated sleeve and insulation is carried out to the deflector if the hood passes through the main wall.
In private buildings, ventilation ducts are directed through unheated attics and go outside through the roof or gables. The insulation is applied, starting from the place of potential freezing of the ventilation duct.

A separate issue is the supply system, where the formation of condensate is interconnected with the length and location of the ventilation duct. Such channels can be insulated in the same way as exhaust channels, but the influx of cold air causes discomfort to residents, and the dampers of the supply system may freeze.

You can solve the problem with an insulated ventilation valve. In fact, these are blinds that regulate air flow and, if necessary, heat it due to the operation of tubular heaters.

Heating elements that heat the air do not serve to increase the temperature in the room, but only to prevent icing of the valve flaps. The valves can be adjusted manually or electrically.

Complex answer

Sometimes you need to make accurate calculations, since with a significant length of the ventilation system, the financial costs will be large, and no one wants to spend extra money. The main parameter is the dew point. It refers to the temperature at which condensation occurs in air masses with a certain degree of humidity.

Determining the relative humidity of the air in the building and the surface temperature in different places of the ventilation duct will allow you to set the exact boundaries within which you need to carry out insulation.

Advice! Even if the exact boundaries of the zone for insulation are known, it is better to expand them slightly towards the room. This will slightly increase costs, but will protect the system if the temperature drops too much.

materials

The heater must meet certain requirements:

the main quality is the level of thermal insulation;
fire safety - the ventilation duct should not facilitate the task of the flame in the event of a fire;
the cost of thermal insulation should not be too high.

Please note: only the insulation of the outer part of the ventilation ducts is considered here. The use of internal insulation will require complete disassembly of the system. Also, the useful cross section will be significantly reduced.

Mineral wool

Material advantages:

The lowest cost among competing heaters.
Fire safety.

Difficulty in installation. First, ventilation is covered with a layer of mineral wool. After that, foil is applied (if we are talking about the interior) or galvanized metal. And, finally, the structure is covered with bandages.
The material is unsafe for the organs of vision and respiration.
Mineral wool caking over time, gaps appear in the insulating layer.
The material is subject to the harmful effects of moisture, which gradually reduces its heat-insulating properties. Typically, mineral wool must be replaced after 2-3 years of operation.

The best consumer characteristics are possessed by another material, including mineral wool - insulated corrugation. The insulation is a two-layer sleeve made of aluminum foil reinforced with wire. This option of insulation can only be used when creating a new ventilation system.

Styrofoam

Advantages of foam insulation:

The heater is safe for health and easy to install. For insulation, it is enough to wrap the pipe in two foam shells and squeeze them, after which the spike will enter the groove. If the ventilation duct is long, the halves are placed with some offset.
Styrofoam is not only an excellent heat insulator, but also a material that retains its properties regardless of the level of humidity.
The cost of foam is low.

Material disadvantages:

Toxicity on fire.
Insulation in the form of a shell is easy to use only on straight lines of the ventilation duct.

Polyurethane foam, polypropylene foam

Insulation in the form of two halves for connection is also made from other materials - polypropylene and polyurethane foam.

The difference between the indicated heat insulators and foam:

polyurethane foam and polypropylene foam are stronger than polystyrene;
the cost of these materials is higher;
fixation is necessary, which is done with a wire bandage.

Foamed polyethylene

Such material is made in the form of split tubes of various diameters. The entire installation consists in putting such tubes on the ventilation duct.

The advantage of the material is moisture resistance, resistance to mechanical stress (for example, from rodents).

There are also other materials based on polyethylene foam, which are even more resistant to frost:

Penofol, which is a combination of polyethylene foam and aluminum foil. An additional advantage of penofol is resistance to dust formation due to the presence of pores on its surface.
Self-adhesive polyethylene heat insulator. The insulation is attached due to the presence of a sticky layer on it. The thickness of the self-adhesive insulator is 10 mm and can be applied in several layers.

Insulation of pipes with a square profile

Square pipes are best insulated with slab insulators made of expanded polystyrene (with a layer of foil), polystyrene, basalt wool. The material, cut in the form of plates, is applied to the ventilation duct. Expanded polystyrene and polystyrene are glued with one type of special glue, and another adhesive is used for mineral and basalt wool.

Insulation of square channels is similar to lining a pipe with bricks. The gaps between the plates are laid with pieces of insulation and sealed. If the ventilation duct is made of metal, the requirements for vapor barrier are small, but it is still better to cover the pipe with a liquid waterproofing layer.

External air ducts are insulated with an additional layer of reinforcing tape covered with foil or rolled waterproofing materials.

Insulation of round pipes

If the pipe has a circular cross section, plate heaters are not used. In this case, roll materials are applicable. Such heaters are characterized by high fire safety and improved sound insulation properties.

If funds are limited, instead of branded roll insulation, it is possible to use ordinary mineral wool. You can wrap the ventilation duct twice with mineral wool with your own hands and compress it with clamps.

Areas located outside the attic are lined with a layer of waterproofing (roofing material). Bitumen-polymer waterproofing materials are also used.

The optimal solution for thermal insulation in terms of quality is polyethylene foam foil. However, the choice of a specific material for ventilation insulation depends, first of all, on the budget of the interested party.

Everyone knows why ventilation is needed - it provides the room with fresh air and normalizes the level of humidity. But why they do the insulation of ventilation pipes, not everyone knows. Next, we will try to answer this question, and also consider the types of heat-insulating materials and how to install them on ventilation pipes.

Why insulate ventilation

Many people doubt whether it is necessary to insulate the ventilation pipes, because they do not fully understand the meaning of this procedure. And it is performed for one reason - to prevent the appearance of condensate.

On an uninsulated air duct, condensate inevitably appears, which flows down the inner walls, flowing into the ceiling and main walls.

The implications of this are obvious:

Damp walls and ceiling;
Mold appears;
The building is gradually falling apart.

As for the effect of condensate on the ventilation duct, it depends on the material from which the duct is made:

In addition, there is another unpleasant moment associated with the formation of condensate - freezing of frost, which can occur outside the heated room, i.e. in the attic. As a result, the clearance in the pipe can drop from 100 or even 150 mm to zero in a few frosty weeks.

From this we can conclude that it is really necessary to insulate ventilation pipes, moreover, for several reasons at once.

In the photo - insulated heat-insulating pipe in the attic

Where to insulate ventilation

Depending on the type of duct construction, its insulation can be performed in different areas:

If the ventilation pipe is brought out through the wall, it must be passed through a thermally insulated sleeve. In this case, the pipe is insulated to the very.
In private houses, most often ventilation passes through the attic and goes outside through the roof or gables.. In this case, the section of the duct located in the attic is insulated.

materials

Before insulating ventilation pipes with your own hands, of course, you must choose a heater. Currently, there are quite a few thermal insulation materials on the market, which somewhat complicates the choice. Therefore, first of all, it is necessary to determine the requirements for insulation.

In this case, the following characteristics of the insulation are the most priority:

Good thermal insulation qualities are perhaps the most important requirement.
Fire safety - in case of fire, the pipe should not become a highway for the spread of fire.
Cost - it is desirable that the price of the material be affordable.

Now let's look at various heaters that more or less meet these requirements.

One of the most common types of insulation is mineral wool.

Its advantages include the following points:

Cheap - any other insulation is more expensive.
Fire safety.
Good thermal insulation qualities.

However, this material also has some disadvantages:

Pretty complicated installation.
Over time, cotton wool becomes caked, and gaps form in the insulation.
When moistened, thermal insulation qualities are lost.
The need to protect the eyes and respiratory organs during installation. In addition, getting on the skin, mineral wool causes irritation.

Instructions for insulating the duct with mineral wool are as follows:

First of all, you need to wrap the pipe with mineral wool.
Then the heat insulator is wrapped with aluminum foil. If external insulation is performed, then a galvanized casing should be used instead of foil.

Advice!
More convenient to install is a ready-made insulation for ventilation pipes, made on the basis of glass wool.
The product is a multilayer corrugated sleeve made of aluminum foil, between the layers of which there is a heat-insulating material.

Styrofoam

This insulation is a ready-made, made of dense foam.

Among its advantages are such points as:

Simplicity and convenience of installation.
Low cost.
Over time, the material does not lose its thermal insulation properties. They are not affected by fluctuations in humidity.

As for the shortcomings, there are only two significant ones:

Styrofoam burns well and at the same time releases toxic substances;
The foam shell can only be used on flat sections of ventilation pipes.

It is extremely simple to carry out insulation with this material - two halves of the heat insulator must be put on the ventilation pipe and squeezed so that the thorn-groove connection is fixed.

Advice!
When insulating a long duct, the halves of the insulation are installed with a slight vertical offset, which ensures their bandaging.

Polyurethane foam and polypropylene foam

These heaters are in many ways similar to foam, however, there are still differences and they consist in the following points:

They have greater mechanical strength than polystyrene.
Their cost is higher.
The fixation of the halves is carried out using a bandage, which is most often used as a knitting wire.

Thus, if the cost of the material does not play a role for you, then it is better to insulate the air duct with polyurethane foam or polypropylene foam.

Here, perhaps, are all the heaters most suitable for these purposes.

Conclusion

Insulation of ventilation pipes in the attic is a mandatory procedure that ensures not only the normal functioning of the system at any time of the year, but also the safety of the entire building. As for the choice of insulation, you can give preference to any of the above options.

See the video in this article for more information on this topic.

To maintain optimal humidity and temperature conditions in the premises, it is necessary to insulate the ventilation pipes. Thermal insulation of ventilation systems prevents the formation of condensate, which leads to the gradual destruction of pipes, the loss of their original operational and technical parameters.

External and internal thermal insulation of ventilation pipes

Insulation of exhaust pipes performs the following functions:

Provides fire resistance, prevents the spread of fire in case of ignition.
Prevents the formation of condensate on the outer and inner surface of the pipe.
Reduces heat transfer between the outside environment and the air in the system.
Reduces vibration and noise generated during air movement.

Insulation of the ventilation pipe can be done from the inside or outside. With internal thermal insulation, it is required to increase its cross section to maintain the required throughput of the duct.

Today, providing sound insulation through thermal insulation material is not relevant, since often this problem is now solved by soundproofing measures in the sound source or by installing silencers. Therefore, at the moment, the use of external insulation is preferable.

Another circumstance when choosing whether it is necessary to insulate the ventilation pipe internally is the possibility of the appearance of foci of bacteria with such a decision, the appearance of deposits of dirt and dust, due to which the material may begin to lose its properties. With external insulation, these disadvantages are absent. Thermal insulation outside the pipe in the event of a fire greatly reduces the risk of fire spreading.

Materials for insulation of ventilation systems

Thermal insulation of ventilation pipes is made using various materials:

mineral fibers. Thermal insulation materials made of glass wool or mineral wool are produced in the form of semi-rigid or rigid pipe panels and sections, in the form of a material that can be given the required shape and density by pressing during installation.
Felt. During internal laying, rolled felt is protected with glass fiber with surface impregnation. At the outside - aluminum reinforced kraft sheet. Pipe sections are used for external cladding with aluminum reinforced protection.
Foam elastomers are flexible, closed cell foams. They are self-extinguishing materials. This insulation is not subject to the action of microorganisms and mold, resistant to vapor permeation and moisture absorption.
Derivatives of polymerization of carbohydrates (polyethylene, polyurethane, polyvinyl chloride). As a rule, they are produced in the form of pipe sections, blocks, plates.

Installation of thermal insulation on ventilation pipes

Expanded polystyrene insulation

Ventilation pipes insulated with polystyrene foam are less susceptible to corrosion, which greatly increases their service life.

To install the polystyrene shell, you do not need special skills. For its installation:

Determine the size of shell you need.
Cut the shell with a saw or knife.
Install the parts of the shell on the pipe with an offset of several centimeters between each other, carefully close the side joints.

From the ventilation pipes, which are insulated with polystyrene foam shells, in the event of an emergency, they are quite easy to dismantle and just as easy to install back.

Polypropylene and polyurethane foam

These materials have significantly lower thermal conductivity and high refractoriness. Ventilation pipes are insulated with polyurethane foam and polypropylene as follows:

Determine the required size.
Cut material into semi-cylinders.
Provide an allowance for the cover layer.
Install half-cylinders on the ventilation pipes.
Securely fasten the joints with bandages.

Polyethylene foam insulation

This material insulated pipe for ventilation is the most popular today. Foamed polyethylene is a ready-made shell that completely encloses and insulates pipes.

For pipe insulation:

Take material measurements.
Divide the insulating sheath along a special seam.
Fix the shell on the pipe.
Using mounting tape or glue, fix the joints and seams of the insulating shells.

For square-section air ducts, polyethylene foam is produced in rolls (for example, Energoflex Star Duct)

Regardless of how to insulate the chimney, the location of the heat-insulating material, the main thing is to prevent cold bridges, which reduce the effectiveness of insulation, and ensure high vapor resistance. To do this, special attention must be paid to the joints of the channels with the structures of the building, where there is the greatest probability of the appearance of cold bridges.

In this material, we will fully analyze the problem of the need to insulate ventilation pipes in an unheated attic. Consider the feasibility of thermal insulation of pipes, how to do it correctly and what materials to give preference to.

Ventilation pipes on the roof and attic are insulated in order to reduce the risk of condensation: it accumulates inside an uninsulated pipe. The resulting condensate flows down the pipes, penetrating into the joints and cracks, due to which wet spots form on the walls or in the ceiling. At sub-zero temperatures, this can cause the formation of frost, which reduces the internal diameter of the pipe.
This is due to the high content of moisture in the warm air. During the cold period, warm air comes into contact with a cold pipe, it cools sharply, as a result of which steam is formed, and then condensate. This process can be stopped with the help of pipe insulation.

Ventilation pipe being prepared for insulation

Advantages of insulation

During the operation of the hood, noise occurs, the level of which can be reduced by insulating pipes;
When choosing a high-quality insulation, the air duct minimizes heat loss, since the heat exchange between the warm air inside the pipe and the cooled outside is reduced.

Important! Some modern manufacturers already provide thermal insulation.

Negative consequences of the lack of insulation

The condensate accumulating in the ventilation shaft adversely affects the floors. Condensation also leads to:

Formation of rust on a galvanized pipe;
Depressurization of the ventilation system;
Reducing the inner part of the duct;
Decreased quality indicators of air exchange;
The appearance of moisture in the ceilings between floors, in the middle of wall structures, and so on

The consequences of the negative impact of condensate from an uninsulated pipe

The lack of pipe insulation can lead to rapid deterioration of the building in the cold season. At lower temperatures, more condensation will form, so insulation of ventilation pipes in a cold attic and roof is necessary.

Where should pipes be insulated?

Thermal insulation is necessary in places of the largest area of contact between cold air and warm air. If the ventilation pipe in your house is led through the wall, then it is necessary to insulate the part leading to the deflector. In private homes, another cold place is the attic. If the pipes pass there, they must be insulated.

In office, industrial premises, an insulated ventilation valve is created. It opens or closes access for air streams of different temperatures. The valve can heat the outgoing air, as the flaps are treated with a heating element, which reduces the risk of condensation. This method is quite expensive.

Important! To start installing insulation yourself, you need to find the place where condensate appears - the temperature dew point.

Internal and external insulation: pros and cons

Pipes can be insulated in two ways: internal lining or insulation of the outside. Each method has its own advantages and disadvantages.

Internal lining

More difficult to install, but not subject to external mechanical temperature effects.
In order to avoid reducing the inside of the duct, some work must be done to increase the initial area.
The material must be vapor-tight and airtight to avoid absorbing moisture from the air.
The outer part of the material must be smooth so as not to impede air circulation.

An example of external insulation of a ventilation duct

Outside insulation

Easier to install, but the material must also be vapor-tight.
It is necessary to provide for the insulation of the exhaust pipe and the installation of a hydrobarrier.
The material must withstand mechanical stress.
The insulation must be non-combustible, as in the event of an open fire, it comes into contact with air.
This type of insulation does not reduce the internal cross-sectional area of the pipe.
It is not susceptible to the formation of pathogenic bacteria in it.

Materials for insulation of the ventilation pipe

Must meet these criteria:

Fire resistance.
Good thermal insulation qualities.
Budget.

Consider the most commonly used materials for this purpose.

Mineral wool

Insulation - mineral wool

Has its positive aspects:

The most inexpensive and affordable heater.
Fireproof.

There are also negative aspects:

The process of warming with mineral wool is quite complicated. First, it wraps around the pipe, then galvanized or foil around the cotton wool, then the structure must be pulled together with a bandage.
It sticks over time. Because of this, open areas are formed between the insulation and the surface of the pipe.
Cotton wool can lose its thermal insulation properties with a sharp increase in humidity levels.

Important! Mineral wool is toxic to humans! Protective equipment is required during installation.

Styrofoam

Foam insulation for pipes

For thermal insulation of pipes, ready-made detachable structures made of expanded polystyrene are used.

Advantages of foam:

Easy to install: the finished pipe has tongue and groove joints. The design is put on the pipe and pressed against each other, thereby forming a strong connection.
Does not change its characteristics due to a sharp increase / decrease in the level of humidity.
Budget.

Foam Disadvantages:

Flammability. Also, during combustion, fumes toxic to humans are released from polystyrene foam.
Ready-made forms cannot be used on bends, only suitable for open straight pipe sections.

Polyurethane foam and polypropylene foam

Polyurethane foam shell for steel pipe insulation

The design is similar to a foam pipe

They are high priced.
Differ in special mechanical durability.
Requires an additional layer during installation: it is necessary to use a tie-wire bandage.

Foamed polyethylene

A fairly common solution and inexpensive

It is a tube with different diameters and sizes.

Advantages:

Easy to install - you just need to put it on the pipe.
It is not subject to external mechanical influence.
The structure of the foamed polyethylene makes it impossible for the appearance of rodents.

For residents of a predominantly cold climate, the following materials are suitable:

Penofol - polyethylene foam with a layer of aluminum foil. The use of penofol prevents the accumulation of dust and other types of contaminants.
Self-adhesive insulation based on polyethylene foam. This material is very easy to install: it is necessary to remove the protective film and press it to the surface of the pipe. For greater insulation, it can be glued in two or more layers.

It looks like ventilation ducts, thermally insulated with penofol

From this material, you learned some of the features of the ventilation pipe in the attic or roof and got acquainted with different types of materials. The next choice is up to you.

The order of work on the insulation of pipes

To insulate the vent pipe with styrofoam, follow these steps:

Find out the exact dimensions of the pipe, including the inner diameter.
Make cuts with a knife or saw.
Place the fragments of the cylinder on the pipe, move them a few centimeters.
Forcefully close the parts on the sides with the tongue-and-groove interlock.

This design is easy to install and dismantle.

It is also possible to use structural elements with factory insulation.

To insulate the pipe with a finished polyethylene foam shell, you must perform the following steps:

For a snug fit of the insulation, take all the necessary measurements.
Find a special seam on the capsule.
Separate the capsule along this seam.
Fix the material on the pipe.
Insulate the joints with tape or glue.

For insulation made of fire-resistant polypropylene or polyurethane foam, you must perform:

Taking the necessary measurements from the pipe to determine the size of the material used.
Cutting the workpiece into semi-cylindrical segments. It is necessary to take into account the margin for the cover layer.
Formation of cut blanks capsules.
Fastening joints with bandages.

For a rectangular vent:

It is necessary to find a slab or roll insulation of the required thickness (basalt fiber is suitable).
The material is cut into fragments necessary for mounting.
Pieces of material are fastened together with pre-calcined steel wire.
Seams are sealed with strips of foil with an adhesive layer.

All these methods of isolation have a common drawback - "cold bridges". To avoid their formation, it is necessary to follow the technology of work during the installation process. You also need to carefully isolate the joints and seams between the structures of the house and the ventilation ducts.

Video: an example of insulation of air conditioning ducts in a residential building

Chimney insulation in the attic

Condensation is also possible inside a chimney passing through a non-residential cold attic or roof. To avoid this, you can insulate the pipe with polyurethane foam (PPU). The second option is to use sleeves - "sandwich pipes" - integral insulated parts of the chimney.

In addition to liquid insulation in the form of foam, it is possible to use double pipes made of "sandwich pipes", sleeves and thermal insulation material. This type of insulation performs the function of heat saving and prevents the formation of condensate due to the foil screen.

The principle of thermal insulation of the chimney

With a high probability of freezing of the pipe, a heat-insulating electrical cable is used. It is wrapped around the pipe or fixed next to it. Some pipes have a built-in heating cable.

Kaolin slabs are used to insulate a brick pipe. For their installation, a special solution is prepared and glued to the pipe. From above the plates are covered with plaster. Kaolin slabs are one of the most reliable ways to insulate brick pipes.

Insulating pipes on a roof or attic is a simple task that can be done alone if you know some of the features of the technique.

Advantages and disadvantages of finished insulated pipes

For those who do not want to engage in insulation on their own, there are ready-made insulated pipes with a layer of factory insulation. They have a simple design: a protective layer of basalt fiber is inserted between two channels of different diameters.

Specifications

Such pipes are used in the construction of ventilation systems and chimneys. In the first case, it is necessary to use galvanized products, in the second - stainless steel. Protection against moisture and heat preservation is provided by a layer of mineral wool with the following characteristics:

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

Finished insulated pipes

The mineral base prevents the formation of fungus and mold, and the fiber structure is preserved even after a long service life. The melting temperature of the insulating insert is 1100 ºС, which indicates the fire safety of the product. The combined composition makes the product absorbing internal noise and durable. The disadvantage of this product is the high price.

Installation Features

If you decide to mount the structure yourself, the following reminders can help you:

With a wide cross-section of pipes, the circulation of air flows is better (the recommended minimum diameter is 14 cm).
Short channels must be made wide enough.
To maintain traction, all air ducts in the house must match each other.
It is better to use the same type of thermal insulation and pipes.
Forced ventilation should be installed in case of violation of natural heat transfer.

Insulation installation process

Video: an effective way to insulate a chimney

Possible ways to prevent deficiencies

Insulated pipes have no drawbacks that would affect operation .

However, it should be borne in mind that several steel layers will be heavier than corrugated or polymer insulation. However, the quality of the installation is not affected by the installation process, so this characteristic is rarely taken into account.

If there are doubts about the cost, a simple calculation can be made: compare the difference between the insulated structures with the sum of the costs of pipe sets, insulation with waterproofing and the cost of fixation devices. If the difference is small, it is necessary to choose a material that is easier to install.

Outcome

Insulation of pipes in a cold attic or roof is necessary. The material should be chosen based on your budget and the characteristics of a particular house.

It happens that a newly created ventilation system in a private house in the summer works flawlessly, pleases with efficiency and presentability. However, with the advent of winter, the homeowner suddenly discovers that a small amount of frost appears on the outside of the air duct. It is not difficult to guess that this is a signal for action, otherwise, after a relatively short period of time, the pipe will begin to collapse. As a result, a serious material resource will be required to fix the problem. And, if you react in time, then you just need to buy a heater 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 outer surfaces of the ventilation pipe indicates that condensate accumulates inside the duct, which is fraught with:

rust on galvanized pipe;
depressurization of the ventilation system;
reduction of the area of the flowing part of the air duct;
decrease in quality indicators of air exchange;
penetration of moisture into the middle of wall structures and ceilings between floors, etc.

In a word, poor ventilation in winter will lead to physical deterioration of the entire building. Moisture on the walls of the ventilation passages will form the more, the greater the difference between the temperature indicators of the air flows moving through the pipes and the air outside (on the street). Hence the positive answer to the question, is it necessary to insulate the ventilation exhaust pipe in a private house?

Solving a set of problems with the help of insulation

The ventilation “set” includes a list of equipment for supplying and removing air flows that maintain the required microclimate characteristics inside the premises. This also includes air ducts: transport air "arteries" passing from the side of the street and indoors.

In order for the air channels to have the necessary strength indicator, the necessary cross-country ability, their proper insulation is required. For this, norms are adopted that ensure sanitary and epidemiological stability in residential buildings. Do not neglect the requirements of building rules and regulations in terms of heating, organization of ventilation and air conditioning, as well as the use of thermal insulation and protection of buildings from heat losses.

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

does not allow the moisture that has fallen out of the air to settle on the surfaces of ventilation structures;
increases the resistance of structures to fire;
helps to reduce heat loss;
"quenches" the high generating frequencies of sound and vibration vibrations.

Criteria for choosing insulation for ventilation insulation

You need to know how and how to insulate pipes for ventilation. When choosing, the advantage is given to the thermal resistance of the material. The main role of the insulation is to bring the temperature on the surface of the pipe to the maximum amount of air leaving it. In this way, condensation can be avoided. For this purpose, materials based on mineral fiber (stone and mineral wool, fiberglass), foam elastomers, and polyacrylates are used: polystyrene - a product of styrene polymerization, polyurethane, etc.

Insulation based on metal and glass threads obtained from inorganic components is supplied to the trade network in the form of plates or rigid (semi-rigid) rolled materials. The choice is simplified by a wide range of heaters with different densities, prices and thermal insulation characteristics. The indisputable advantage of mineral wool insulation is its resistance to decay and fire resistance.

Attention! If you do not know how to insulate the 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 sleeves are insulated with fiberglass treated with a special impregnation.

Arguments in favor of internal and external insulation

Insulated pipes for ventilation are either lining from the inside or external insulation. Each method is characterized ambiguously.

Interior finish:

it is more difficult to carry out work inside the duct, but the insulation itself is protected from external temperature, mechanical influences;
laying the layer inside will lead to a decrease in the useful working section of the duct, which requires preliminary work to increase it;
interior decoration must be airtight 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.

External pipe protection is easier to install, but also only in a vapor-tight version. At the same time, it is necessary to provide for how to insulate the ventilation exhaust pipe that rises above the living space, and what kind of hydraulic barrier to make. The outer protective shell should protect the exhaust structures from mechanical damage. An important requirement for insulation is incombustibility, because. when an open flame appears and contact with atmospheric oxygen, the degree of ignition of the insulation increases significantly. External insulation does not affect the size of the internal section of the ventilation duct and does not require its expansion. And pathogenic organisms (viruses, bacteria), which often occupy inside the walls of air ducts and, being in isolation, are protected from adverse conditions, do not take root in the insulation layer from the outside.

Pipe insulation: work procedure

When isolating ventilation with a polystyrene shell, the following is carried out:

clarification of the dimensions of the ventilation pipe, in particular, the inner diameter;
making cuts with a knife (you can use a saw);
coverage by fragments of the cylinder (shell) of the pipe, their displacement between themselves by a couple of centimeters;
closing with force of the lock interface "comb-groove" of the parts on the sides.

The structure (shell) is easily installed and dismantled in case of work with the pipe.

Works on insulation with foamed polyethylene in the form of a finished shell of a ventilation pipe are as follows:

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

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

dimensions are determined;
semi-cylindrical segments are cut from a solid workpiece with a margin for the cover layer;
a capsule is formed from the 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:

a rolled or slab insulation of the required thickness is selected (for example, basalt fiber);
it is cut and cut to size into fragments that are convenient to assemble when facing;
with the help of steel wire, previously calcined, the pieces are fastened together;
seams are hermetically sealed with strips of foil with an adhesive layer applied to it.

Thermal insulation for ventilation by any of these methods, with 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 the ventilation ducts and the structures of the house are especially carefully isolated, otherwise the effect expected from the insulation will decrease.