Hood pipes: choice of plastic ventilation pipes

Laying communications in a house or apartment is not as simple as it seems at first glance. In order for the equipment to work normally, as well as there were no complaints from the testing authorities, it is necessary to carry out the installation taking into account all the rules and regulations, not forgetting the aesthetic component.

We will tell you how to correctly select the best pipes for exhaust, focusing on their technical and practical qualities. With us you will learn how to choose the optimal section and calculate its size. Together we will understand the set of components from which the ventilation ducts are assembled.

Independent masters, we offer two options for installing plastic ducts. The information submitted for consideration is supplemented with schemes, photo clips, video tutorials.

The content of the article:

  • The use of ventilation pipes in the home
  • The main characteristics of plastic parts
    • Material manufacturing duct
    • Types of pipes according to the degree of flexibility
    • Variety of elements in the form of section
    • How to choose the size of the section?
    • What does exhaust ventilation consist of?
  • Plastic pipe mounting options
    • Option 1. Indoor duct installation
    • Option # 2. Thermal insulation of pipes in the attic
  • Conclusions and useful video on the topic

The use of ventilation pipes in the home

Ventilation pipes with a set of connecting and fastening elements are called air ducts. They are designed to provide air circulation and are installed in rooms where there is no access to natural air movement or there is an additional need for airing: in kitchens, in bathrooms rooms, toilets.

Before the appearance of plastic parts on the market, the air ducts were made of galvanized metal, and now they are often are found in production workshops or in catering establishments (their use is associated with high temperatures).

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Plastic duct option

The construction of ducts made of plastic pipes allows you to get rid of all the shortcomings of metal structures

Polypropylene elements

For the device ventilation channels produce a full range of products, providing the ability to assemble a system of any degree of complexity.

Parts for ventilation of polyvinyl chloride

Plastic collected ventilation systems are resistant to chemical, biological, mechanical stress.

Valuable benefits of moisture resistance

Plastic ventilation systems do not rust and do not oxidize in wet rooms, mold and fungus do not settle on their walls.

Features of the use of PVC pipes

The disadvantage of polyvinyl chloride air ducts is that they are not recommended to be located near the heating equipment and installed in areas where direct exposure to sunlight is likely

Aerodynamic resistance

Polymer pipes are distinguished by high aerodynamic resistance; they are used in the device of both natural and forced ventilation systems.

Production hood

Plastic parts for the construction of air ducts in the priority at the enterprises, if you need high-quality removal of aggressive environment

Plastic ventilation duct

Polymer elements are excellent for ventilation in apartments and private houses due to their lightness, durability, service life of 50 years.

Plastic duct option

Plastic duct option

Polypropylene elements

Polypropylene elements

Parts for ventilation of polyvinyl chloride

Parts for ventilation of polyvinyl chloride

Valuable benefits of moisture resistance

Valuable benefits of moisture resistance

Features of the use of PVC pipes

Features of the use of PVC pipes

Aerodynamic resistance

Aerodynamic resistance

Production hood

Production hood

Plastic ventilation duct

Plastic ventilation duct

But for use in everyday life, that is, for the installation of ventilation in apartments and cottages, are more suitable polymer products.

They have the following advantages:

  • have less weight than metal, so they are easier to install with your own hands;
  • smooth walls have minimal resistance to moving air;
  • tight, as they have no seams;
  • resistant to the effects of high humidity, does not rust;
  • On sale you can always find a set of fittings that fit the section.

Products that meet state standards and have certificates of conformity are allowed for sale, so you can talk about the safety of plastic elements.

Details of air ducts for exhaust

Stand in the supermarket with plastic elements of the ventilation system assembly for the hood: rectangular and circular pipes, adapters, tees, plugs, corner parts

The main characteristics of plastic parts

The properties of pipes must be known in order to properly design and install a ventilation system in an apartment or house. The characteristics of the elements may vary depending on the installation site (above the plasterboard ceiling, in the closet, in the attic) and on the geometry of the room.

Consider what features are decisive when choosing.

Material manufacturing duct

On sale you can find products to create ventilation structures of four types of material, which are commonly called plastic in everyday life:

  • polyvinyl chloride;
  • polypropylene;
  • polyurethane;
  • polyethylene.

Polyvinyl chloride Lightweight, inexpensive, easy to install PVC air ducts - the most common material for the construction of domestic ventilation structures. They are durable, tight, but have some limitations.

They cannot be heated to 160 ° C, as chlorine harmful to all living things begins to be emitted, and according to the standards, the upper heating bar without risk to human health is + 120 ° C.

PVC pipe installation

PVC pipes are suitable for installation in the kitchen or bathroom, their use is prohibited where there is a possibility of heating to 160-180 ° C - for example, in saunas or in rooms with a fireplace

When the temperature drops below + 5 ° C, PVC becomes brittle, therefore for mounting the ventilation system in rooms with temporary residence it is better to choose another type of pipes, for example, from polyethylene or vinurethane.

Polypropylene - the fine dielectric, is not hygroscopic, has high resistance to aggressive chemical environments. The tensile strength is about 4 times higher than that of high-pressure polyethylene products.

The main drawback is flammability, the maximum possible temperature is + 85ºС. However, there is a flame retardant version with flame retardant additives - PPS.

Polyurethane according to its characteristics, it resembles PVC, but withstands higher temperatures - up to + 280ºС.

Reinforced Polyurethane Pipe

Particularly durable is viniuretan, reinforced with a steel spiral. It is suitable for exhaust, as it has excellent resistance to mechanical damage and flexibility, allowing you to deploy the duct at any angle

HDPE - low-pressure polyethylene. It does not crack with time and, unlike PVC, it tolerates negative temperatures more easily (important for homes with temporary residence). Possible heat resistance - up to + 80 ºС, cooling - up to -50 ºС. Easy to handle, like all types of plastic products.

Polypropylene and polyethylene pipes for household ventilation are rarely used, their PVC products are leading.

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Conclusion funeral riser on the street

From polypropylene sewer pipes can be built fan stand with the laying of the main route of the pipe on the street

Marking the wall for installing clamps

A hole is made from the hole drilled by a perforator and equipped with an angle-fitting fitting and mounts are installed for the funnel pipe.

Installation of clamps in fixed dowels

In the holes drilled in the wall, the dowels, necessary for fastening the clamps, are hammered.

The construction of the riser from sewer pipes

Further actions are to install the pipe, the elements of which are connected using silicone sealant

Conclusion funeral riser on the street

Conclusion funeral riser on the street

Marking the wall for installing clamps

Marking the wall for installing clamps

Installation of clamps in fixed dowels

Installation of clamps in fixed dowels

The construction of the riser from sewer pipes

The construction of the riser from sewer pipes

Types of pipes according to the degree of flexibility

There are two categories of plastic ventilation pipes for exhaust - rigid and flexible. Sometimes a combination is also needed, but much less frequently. If the hood is installed near a vent, there is no need for a complex construction.

When purchasing rigid pipes of round or rectangular cross-section, it is necessary to purchase a set of additional parts in order to arrange turns or transition points.

PVC construction assembly

To assemble a short duct for the hood, located above the kitchen cabinet, rectangular PVC channels and connecting corner elements of similar material were used.

Along with rigid straight pipes, corrugation is used - flexible polyurethane products or aluminum, allowing to do without angular details.

Corrugated pipe application

Use of aluminum corrugated pipe as an air duct, which has two advantages over plastic analogues: fire resistance and higher strength

Corrugated products are more economical, but lose in design. In order to preserve a beautiful view of the interior, it is better to disguise them under the suspended structures or place them in a “blind” zone - on the cabinets against the wall.

Variety of elements in the form of section

Depending on the configuration of the pipe, air ducts of the following types are emitted:

  • round;
  • rectangular;
  • flat.

The shape of the section largely affects the technical characteristics and method of installation. For example, straight round tubes have better throughput and excellent sound insulation, since the air, moving along smooth walls, practically does not meet any obstacles (except for the angular sectors).

However, due to the cylindrical shape, installation problems may occur.

Circular tube installation

The option of mounting a round pipe leading from the exhaust hood to an air vent on an adjacent wall. Mounting elements: 4 pipe lengths, 3 round elbows 90º, gear (+)

Rectangular air ducts fits snugly to any flat surfaces (walls, ceiling, walls of kitchen cabinets), so installing them is much easier. But there is one drawback - the uneven distribution of air, due to which there is a strong noise.

The device of an extract from plastic pipes

The optimal solution for installing ventilation above the suspended ceiling: lightweight plastic pipes of rectangular section with a set of adapters and an output round pipe (to reduce noise)

Flat ducting - these are the same rectangular, but having a big difference in the dimensions of the width and height of the section (for example, flat channels 110 mm x 55 mm). Due to their compactness, they are often used for installation with a shortage of free space (for example, over suspended structures or above highly suspended cabinets).

How to choose the size of the section?

The size of the cross section is more important than its shape, since the efficiency of air exchange in the room depends on this parameter. There are norms that take into account the specifics of various rooms, and it is better to focus on them when choosing ventilation elements.

Table of requirements for air exchange

Rooms with high humidity and high dirt content in the air (bathroom or kitchen) should be ventilated more often and more intensively than relatively clean and dry (bedroom, living room) (+)

According to SNiP, the volume of air flow in houses and apartments should be at least 3 m3/ hour at 1 m2 living space, while the number of people living is not counted.

The volume of circulating air for people permanently in the room - 60 m3/ h temporarily staying - 20 m3/ h (referring to places of work, for example, offices).

It is not possible to make an accurate calculation of the cross section by yourself, but there is simplified calculation methods. However, it is better for perfectionists to use the services of an engineer or a special program for which the following data will be necessary:

  • form of air ducts;
  • pipe manufacturing material;
  • internal resistance;
  • indoor temperature.

There is a way to determine the size of the ventilation hole on the floor space. For each square meter of the room there is a 5.4 cm² section of the duct, while the pollution coefficient is important.

For an accurate choice of pipe section, we recommend that you turn to professionals who perform calculations using complex formulas, based on specific data.

What does exhaust ventilation consist of?

For the installation of air ducts some pipes are not enough, shaped elements are necessary - fittings for various purposes. They are used for tight connection of parts into a single system, provide smooth transitions of pipes different diameter, connect the duct with the hood and the vent hole, allow you to create corners 90º.

Plastic fittings

Shaped plastic parts for the assembly of a rectangular duct: connecting and horizontal elbows, plugs, holders, grilles, gearboxes, straight connectors, plates, tees

One of the important elements is the transition (adapter). It is necessary in two cases: when you need to connect pipes of different cross-section or ducts that differ in size.

They are used for assembling structures in rooms of complex geometry, sometimes for fragments embedded in cabinets.

To avoid the effect of reverse thrust and used air did not return to the premises, the air ducts are equipped with a check valve.

This is a built-in frame with a dynamic blade, which opens only in one direction - in the direction of air flow into the ventilation shaft. The valve does not act as a connecting element, but as a part that increases the efficiency of the ventilation operation.

Use fittings

The assembly of a small segment involved two pieces of pipe with a rectangular cross section, a wall plate, a duct connector with an outlet, and an angled horizontal elbow

To ensure one hundred percent sealing, it is necessary to select fittings strictly according to the size of the pipes: for example, for boxes of 150 * 100 mm, bends of the specified size are necessary.

Plastic pipe mounting options

Consider two options for installing plastic pipes. for exhaust ventilation. They differ in both the place of installation and the choice of elements.

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Assembling turning parts

Step 1: Construction of the duct from polymer parts will begin with the assembly of the turning parts of the system

Arrangement of the hole for the hood

Step 2: For the output of the ventilation duct in the common house shaft of an apartment building or a privately built ventilation channel, we arrange a hole

Installation flange with check valve

Step 3: To mount the plastic system to the hole, we mount the flange with a non-return valve, which eliminates the backflow of the spent air mass

Assembling straight duct sections

Step 4: After fitting the turning sections to the installation site, in fact, we measure the length of the air ducts, mark and cut the pipes according to actual dimensions

Installation of the duct from the exhaust

Step 5: Mount the duct section at the exit of the kitchen hood

Installation of the second part of the duct

Step 6: Install the second part of the duct, which runs from the exhaust port to the already constructed section

Electrical connection of the hood

Step 7: Connect the exhaust device to the mains through a voltage regulator

Testing the system in completion

Air ducts of natural and forced ventilation before commissioning are tested for health. A sheet of paper should be attached to the joints, which will react to air leakage through a loose fit of parts.

Assembling turning parts

Assembling turning parts

Arrangement of the hole for the hood

Arrangement of the hole for the hood

Installation flange with check valve

Installation flange with check valve

Assembling straight duct sections

Assembling straight duct sections

Installation of the duct from the exhaust

Installation of the duct from the exhaust

Installation of the second part of the duct

Installation of the second part of the duct

Electrical connection of the hood

Electrical connection of the hood

Testing the system in completion

Testing the system in completion

Option 1. Indoor duct installation

More often plastic pipes for the arrangement of ventilation is used in the kitchen to connect the hood and the ventilation hole located on the wall under the ceiling. To facilitate the work, the hob should be located as close as possible to the outlet.

If it is installed on the opposite side, it is better to move it closer than to pull the duct through the entire kitchen.

The shorter the overall length of the pipes, the better. It is estimated that every turn of the pipe with an angle of 90º reduces the efficiency by 10%, and as many more for every extra meter lose systems longer than 3 meters.

To avoid any questions in the course of work, we produce preliminary calculations and draw up a drawing with an indication of the size and additional parts of the duct.

Installation of a plastic box

As a sample, we often take the option when the outlet vent is located slightly to the side of the installation site of the hood.

To work will require:

  • flat channel for exhaust ventilation 204 * 60 (1.5-2 m);
  • horizontal knee 204 * 60
  • connecting knee;
  • wall plate;
  • round gearbox with an adapter;
  • plastic hacksaw;
  • sandpaper;
  • sealant;
  • marking tool.

Prepare the pipes - from plastic boxes we cut off blanks of the desired length, we clean the edges. If the duct is attached in free space, you can pre-assemble it on the floor, fixing the connecting elements with a sealant.

If part of the structure will be in the closet, first fix it (gearbox + vertical pipe), then connect it with a horizontal pipe with an angled bend.

At the end, we connect the pipe to the hole shaped by the plate with a special fitting. For strength, we anoint the joints with a sealant, heating cannot be used.

Duct installation diagrams

For masking the duct used suspended ceiling structures or wall cabinets. For open space, it is better to choose flat rectangular boxes that become invisible when placed on cabinets (+)

If mounting to a wall or ceiling is necessary, do not use screws. Clamps that tightly cover the pipe are specially provided for this purpose. They are equipped with a rubber seal and are attached with brackets or studs. Some clamps are fixed by a simple snap, which simplifies the installation process.

Choosing a suspended ceiling as a masking facility, try to carry out quality work. Before construction, carefully check the tightness of the duct - for repair or replacement, you will have to disassemble the ceiling construction of plastic panels or drywall.

In the construction of ventilation ducts are used not only plastic products. On the choice of material for the device duct you will learn from popular article our site.

Option # 2. Thermal insulation of pipes in the attic

In a city apartment, exhaust ventilation is reduced to installation of plastic ductsleading up to the hole in the common house mine. In a private house, it does not end there, since there is another segment - from the heated room through the attic to the street.

To prevent condensation on the plastic pipes from cold (the attic is often not heated), make warming.

The best materials for thermal insulation are:

  • basalt wool (glass wool, mineral wool);
  • shell of polymeric materials - polystyrene or foam;
  • polyethylene foam.

An example of basalt wool is Rolled Minwool, non-combustible and tear resistant, with minimal air permeability of 0.3 mg / m × h × Pa, wide range of heat resistance (from –180 ºС to + 500 ºС), hygroscopicity around 1.5% by volume. Service life - up to 35 years.

Rolled insulation for air ducts

In addition to basalt cotton wool, there are other types of Rockwool insulation: thick mats or slabs, wound cylinders with foil-coated coating.

Soft rolls are wrapped around the tubes with overlap, covered on top with foil or roofing paper (if mats are used without waterproofing), fixed by winding with metallic tape or steel wire

Polyfoam and polystyrene foam have the form of rigid tubes, consisting of several segments. Some of them are covered with a layer of foil. The foam has a looser structure, so it is suitable for warming curved fragments. Because of the low price, it is preferred by budget owners.

Characteristics of PPS shells

The table presents the comparative characteristics of PPS shells, which are made of polystyrene PSB-S and have the form of semi-cylinders, fastened with clamps or bandage (+)

Leading positions are occupied by foamed polyethylene Penofol, more elastic than the listed materials. Insulation has a minimum thickness, but at the same time it does not let in moisture (it is covered with waterproofing foil on one or two sides), provides a low noise level and perfectly retains heat.

Penofol installation

For independent warming we recommend to use rolled Penofol S. The secret of easy installation is contained in its structure: thin and lightweight polyethylene is covered on one side with an adhesive layer, on the other - with waterproofing foil

The thickness of the insulation varies from 3 mm to 10 mm, the coefficient of thermal conductivity within 0.038-0.051 W / (m * K), water absorption - up to 0.35%. For installation it is enough to cut the material into pieces of the required size, remove the protective film and stick it on the pipe fragment.

For straight pipes, large in length, you can use a roll to the full width, without cutting.

Particular attention should be paid to the joints, the area of ​​the duct exit to the roof, places of contact with external walls.

Conclusions and useful video on the topic

Informative videos will help you understand the types of plastic pipes and learn more about how to install them.

Video # 1. Installation of a plastic box:

Video # 2. Installation procedure in plasterboard box:

Video # 3. Thermal insulation of ventilation pipes in the garage:

As you can see, the installation of plastic ducts is not complicated and is suitable for independent work. However, when drafting a project, we recommend contacting professionals who know the nuances of installing supply and exhaust ventilation and are able to accurately calculate the dimensions of the elements used.

If you have any questions in the process of familiarization with the information provided by us, please write comments in the box below. Here you can talk about your own experience in the installation of air ducts and share useful information.

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