Installing a ventilation fungus on the roof: types and methods of installing a deflector on an exhaust pipe

Additional types of deflectors

For some types of chimney, reflectors, which are also deflectors, may be suitable. They are mainly used on heating appliances operating on liquid fuels.

Additional mounts are put on these devices, because they are exposed to strong winds. However, this device must be made in accordance with the characteristics of the gas installation.

It is important to take into account that if you make a large reflector, then it will not be able to give the necessary thrust, and even worse, it will slow down the combustion itself.This is due to the fact that a large deflector can pass large masses of air, which, in turn, extinguish the flame. An additional device similar to a fan is mounted in this type of device.

Inside the body itself there are blades bent at a certain angle. These blades are connected in a central node which serves as the axis of rotation.

An additional device similar to a fan is mounted in this type of device. Inside the body itself there are blades bent at a certain angle. These blades are connected in a central node which serves as the axis of rotation.

Downwind deflector protection

Due to the presence of this feature of wind flows, deflectors began to be equipped with special protective devices that help increase the level of thrust in the pipe in any weather. To do this, an axis is installed inside the chimney on two bearings located at different levels.

A semi-cylindrical type screen, a vane sheet and a cover are installed on the axle. It is this design that protects the entire chimney from the effects of the lower wind flow.

After the direction of the wind flow changes, the vane sheet turns, while closing the chimney from the wrong wind flow. Thus, any direction and strength of the wind is not able to block the path of the exhausted smoke, and the draft in the pipe remains the same power.

Do not forget that the deflectors are designed for round pipes, which can be a problem if you have an old brick pipe with a square section. In order to solve this problem, special pipes are used that act as adapters.

With chimneys with a large square section, which are built for fireplace heating systems, it is necessary to use adapters in the form of spacer legs that connect the pipe and the deflector itself. Such legs are made of metal strips, which can be galvanized or qualitatively dyed.

Masonry chimneys need an appropriate transition with an overflow in the right direction, which allows you to connect a round deflector and a square chimney.
In other words, it is not difficult to fix this element of the chimney system in the presence of any type and shape of chimney structures.

The deflector does not have to be bought at a hardware store, because it can be extremely easy to make with your own hands. To do this, it is necessary to calculate the dimensions and shape of the element, after which you can proceed to the manufacturing process.

On galvanized steel sheet, it is necessary to draw the upper and lower cylinders of the future deflector, which is easy to do with an ordinary simple pencil. You can cut the necessary elements with the help of metal scissors, which can easily cope with this task.

As soon as these two parts are cut and filed, which is required for high-quality joining of the two edges of one part, you can begin to fix these edges. As a rule, a welding machine, bolts or rivets are used for this.

It should be noted right away that it is extremely difficult to connect a galvanized steel workpiece using a welding machine, because it quickly burns through thin metal. It is for this reason that rivets or small bolts are most often used.

The finished conical cap must be fixed on the upper cylinder of the deflector.This is done using small brackets from the same sheet steel. Fasten the brackets to the pipe with rivets. Do not forget that the brackets should be attached only to the outer side of the deflector, so as not to create additional obstacles in its inner part for proper air flow and smoke extraction.

It is necessary to fix a cone of the reverse type to the umbrella of the element. In addition, the assembly of all parts of the deflector must be carried out directly on the pipe itself, which will allow high-quality mounting and fixing of each individual part of the structure.

Otherwise, two elements of the system can be poorly connected, which will subsequently cause a malfunction of the structure and the entire chimney as a whole. In some cases, it is simply impossible to make this design on our own.

As a rule, this happens with brick chimneys, which require high-quality adapters or racks. From this we can conclude that it is much easier, more profitable and faster to buy this inexpensive element of the system than to try to make it yourself.

It is worth recalling that for the manufacture of the deflector, only galvanized steel can be used, which successfully resists the formation of rust, which negatively affects the life and quality of the service of such a system element.

What is it and why is it needed

Thanks to the fungi installed on the roof of buildings, carbon dioxide, unwanted odors and excess moisture are removed from the rooms.

Proper ventilation is necessary to maintain a healthy and comfortable microclimate in the house.By removing the exhaust air, the fungi protect the air ducts from rain, snow, debris, insects and small animals. At the same time, modern designs prevent the formation of reverse thrust in strong winds.

How is the fungus

This structure is installed on the roof of the building in accordance with building codes and regulations.

Mushrooms for ventilation consist of the following parts:

• cap,
• vent pipe,
• pass node,
• corrugated pipe for connection with horizontal sections of the duct,
• aerator,
• insulating layer
• fan to remove air when the draft is reduced,
• deflector,
• fixture.

Fungi are an indispensable element in the design of buildings where people are located or materials susceptible to dampness are stored.

Principle of operation

The construction of the ventilation system is based on the property of warm and light gas to rise up, and cold gas to fall down. The greater the distance between the object that produces polluted air and the upper cut of the duct, the stronger the draft and the more efficient the cleaning of the premises.

To prevent the formation of ice, the exhaust pipe and umbrella are insulated in various ways.

Types of shape and design

According to their purpose, fungi are divided into ordinary and heat-resistant. Conventional are used to extract air from bathrooms, kitchens and cellars. Heat-resistant devices are placed on pipes that remove combustion products from boilers and furnaces. The dimensions of the air ducts and hoods directly depend on the volume of exhaust gases. Their diameter varies between 100-300 mm.

The simplest and most inexpensive designs are a pipe, on top of which an umbrella made of sheet metal is fixed. Modern products are more practical and aesthetic. They are initially adapted for mounting on sloping and flat roofs, have a condensate collection cup, a layer of insulation that prevents the formation of ice.

Advantages and disadvantages

Installing fungi on the ventilation system allows you to remove air efficiently, regardless of the area of ​​\u200b\u200bthe slopes and weather conditions.

The advantages of these structures are:

• use of modern lightweight and durable materials,
• preventing foreign objects and liquids from entering the duct,
• isolation of the line from reverse draft and stove smoke.

As for the disadvantages, the modules made in the factory are expensive. This affects the construction estimate when you need to install several fungi.

Service life and approximate price

If we do not take into account extreme situations associated with mechanical impact on the fungus (hurricane, falling branches), then these products have a long service life.

It depends on several factors:

• corrosion resistance,
• strength,
• the presence of a glass for moisture,
• installation quality,
• thermal insulation condition.

The simplest construction of an asbestos-cement pipe and a tin umbrella will last at least 15 years. Modern products made of polymer plastic with UV protection will perform their tasks for 50 years or more.

Additional types of deflectors

For some types of chimney, reflectors, which are also deflectors, may be suitable. They are mainly used on heating appliances operating on liquid fuels.

Additional mounts are put on these devices, because they are exposed to strong winds. However, this device must be made in accordance with the characteristics of the gas installation.

It is important to take into account that if you make a large reflector, then it will not be able to give the necessary thrust, and even worse, it will slow down the combustion itself. This is due to the fact that a large deflector can pass large masses of air, which, in turn, extinguish the flame. An additional device similar to a fan is mounted in this type of device.

Inside the body itself there are blades bent at a certain angle. These blades are connected in a central node which serves as the axis of rotation.

An additional device similar to a fan is mounted in this type of device. Inside the body itself there are blades bent at a certain angle. These blades are connected in a central node which serves as the axis of rotation.

Selection rules

You can choose the optimal deflector based on the goals and objectives that are assigned to it. And also it is worth considering the conditions in which it will operate.

A simple chimney is a cap for a wood-burning chimney, made in the form of an ordinary umbrella, and has the following advantages:

• holds the necessary traction both in calm conditions and on the movement of air masses with a power of up to 10 points;
• does not form excessive pressure on the pipe, due to which even in the conditions of a strong storm the chimney remains in its place, rather the umbrella itself can break off and fly away;
• has a simple and clear design;
• practically does not coke and does not clog, it is quite simply cleaned;
• due to the imperfection of the aerodynamic structure, it is insensitive to the shape of the umbrella; if the building is located in the wind, then the chimney can be made in the form of a tent, this greatly simplifies its use and opens up great opportunities for the implementation of design ideas.

At the same time, there are serious disadvantages, such as:

• in light wind, it reduces traction, and it is the weaker, the stronger the heating element works. This is quite dangerous, because in cold winter weather, in the absence of wind, the stove can “choke” and puff fumes into the living quarters;
• in strong winds, on the contrary, it creates too much thrust. This significantly reduces the efficiency of indoor stoves and fireplaces;
• in gusty winds, it can cause blowing into the pipe and creating a reverse thrust effect.

The aerodynamic open model maintains thrust in any wind within sufficient limits for the efficient operation of furnaces and boilers for liquid fuel and gas. Such deflectors can freeze, they are easily littered and quickly covered with soot and soot, however, they are easy to clean.

The disadvantages include the following:

• complex body of revolution;
• as a result of the load created by air masses, the umbrella itself can easily fly off the chimney, and at the same time, the mechanism of the device’s action itself can roll the pipe itself;
• with strong gusts of wind from 8 points, the lateral pressure on the structure increases significantly and then increases in accordance with the power law;
• open structures quite poorly knock down a strong dynamic load arising from gusts of wind, which is why in no case should such a model be placed on pipes made of brick;
• the modification cannot be used for pyrolysis heat-generating mechanisms, otherwise, if a wind occurs, all pyrolysis gases will be sucked out and the furnace or boiler will simply go out;
• not suitable for creating design elements, as it is unsuitable for decoration, all kinds of blotches and figures only worsen the overall aerodynamic status of the structure as a whole.

By the way, an interesting study was conducted in the United States. There at one time they studied issues related to open deflectors, and installed them on steam locomotives in order to check the degree of increase in efficiency at low speed. At the same time, the result was the most depressing - in the middle course, fire began to break out of the pipe and not a single train could develop its maximum speed. In general, the open version of the deflector should be recommended for any type of heating appliances, with the exception of pyrolysis ones. At the same time, it must be checked and cleaned without fail at least once a quarter. It is optimal for a chimney with a low draft force, it is most effective for wood-burning sauna stoves, there has not been a single case of burning people due to a ventilation deflector in saunas.

Closed or as it is called "perfect" type has such advantages as:

• causes stable traction, which is enough for furnaces and boilers of any type;
• not prone to freezing and clogging from the inside;
• dust and frost formed on the outside do not significantly change the operation of the device.

There are also disadvantages, however, users assure that they are not so significant, namely:

• when exposed to a strong wind, it gives maximum pressure on the pipe, and then it grows linearly, so the chimney under the deflector should be further strengthened with braces;
• has rather complex design and technological parameters;
• cannot be used as a design element, as any additional elements significantly reduce the overall level of aerodynamics.

Models may differ in appearance, purpose and material of execution. Most often, plastic, stainless steel or aluminum are used for the production of deflectors. In rare cases, copper can become a raw material for production. Many users prefer the sandwich model.

Roof ventilation in a cold attic

In any room where there is no ventilation, a normal microclimate is impossible. Insufficient air exchange is the cause of stagnation of air and high humidity, at the next stage, mold begins to grow on the structural elements and a fungus starts. All these factors negatively affect the structure, over time it will begin to deform and lose its purpose. In a private house, the room under the roof can be warm or cold.

Differences between cold and warm roof ventilation

In the first case, the ventilation duct is equipped over the entire slope area with the help of a crate and a counter-crate. Warm air masses enter the under-roofing space at the eaves, rise and exit through the aerator in the roofing strip. It also drains the condensate.

Many owners of private houses, where the room under the roof is not heated, are wondering if roof ventilation is necessary in a cold attic, because no one lives there? Such a system should also be in this case, since it will ensure the safety of the structure itself.

Only for an unheated room, it is arranged differently. In this case, vents are created in the under-roofing eaves for cold air to enter, while warm air goes into the aerator and dormer windows on attic in a private house.

Arrangement of roof ventilation for a cold attic

For the attic, this is the level of the eaves. Here you need to create holes

It is very important to correctly calculate the size of the vents in the attic, so that the inflow and outflow of air is the same. Often, owners of private houses use perforated spotlights.

To create an outflow of air from the attic, there are roof elements such as aerators and a ridge. The direction of flow is formed depending on the characteristics of a particular house:

• if the roof of the house has two slopes, ventilation products are made on the gables - loose sewing of overhangs or holes in the wall, the area of ​​\u200b\u200bchannels should be 0.2% of the attic area,
• if slate or ondulin is used as a roofing material and no vapor barrier has been used, then no additional structures are needed, since the air will circulate along the waves of the coating, the ridge will serve as an outflow element,
• if the roof of the house is flexible or made of ceramics, a “turtle” (valve) is formed,
• a system of two gratings has shown itself well, one is installed with holes downwards, the other can be adjusted,
• on the hip roof, ventilation can be created using two holes, one of which is located at the bottom of the filing, the other is at the top of the ridge,
• also on a hip roof, provided that the overhangs are wooden, bars can be placed with a gap of several millimeters.

Sequence of work

1. Calculation of air exchange. According to SNiP in cold attics, as well as in basements, dormer windows or air vents are necessary for air flow. In total, their area should be 1/400 of the total area of ​​\u200b\u200bthe room.
2. Choice of system of outflow and inflow of air. After performing the calculations, you need to choose a system that will be optimal for your home: an aerator or a ridge, windows or vents. Next, a diagram is drawn up, that is, how many ventilation elements will be, their sizes, how they will be located.
3. Execution of work. When creating an attic ventilation system, you should strictly adhere to the scheme.

Summarizing

From the foregoing, it is clear that the work is not difficult for a home master who knows how to hold a tool in his hands and strictly follow the recommendations of the project. But still, it is better to entrust the development of documentation to specialists. They will calculate the size of the vents in the attic, their location and quantity, according to the characteristics of a particular room. A professionally created project will save you from mistakes and shortcomings, the consequences of which can be disastrous.

Roof ventilation in a cold attic The need to create effective roof ventilation in a cold attic is associated with the formation of the necessary level of comfort in residential premises.Otherwise, heat loss and the formation of condensate are inevitable, and then the appearance of fungus and mold, and even deformation of the house.

What is the principle of the structure of the ventilation passage?

The design features of the ventilation passage, in addition to the removal of dirty air, make it possible to ensure a strong sealing of the roof and protect against the penetration of atmospheric precipitation into the attic. Each node consists of an adapter of a certain diameter, which is inserted into a branch pipe fixed to a concrete sleeve.

Node systems are fixed with anchors, which are included in any standard kit. On a metal base, fastening is also carried out, however, instead of a concrete glass, a similar metal one is built in.

The support ring, which is part of the assembly structure, guarantees a perfect connection between the structure and the roof surface. Clutch flanges provide reliable fastening - the lower one is connected to the air duct, the upper one is the support of the ventilation umbrella, which protects the pipe from precipitation. A ring is placed inside the pipe, which guarantees the removal of condensate.

We mount the ventilation elements correctly

It is important to install penetrations through the roof correctly. To do this, follow a simple step-by-step algorithm:

Mark a hole in the metal tile for the pipe. Then carefully cut it out.
Fix the passage element in the tile. Use self-tapping screws for fastening. Do not forget to apply sealant before fixing it.
Insert the outlet carefully into the lead-through element. The output can be sewer, ventilation, etc.

It is important that the outlet is absolutely vertical. Use a level to check

When you are sure that the outlet is installed correctly, secure it with self-tapping screws.
Connect the outlet of the hood to the air duct, which is located directly inside the house. To do this, you need to use a corrugated pipe. It will be stretched through layers of vapor and waterproofing, as well as through insulation. Be sure to provide good waterproofing in places where it passes. To do this, use adhesive tape, as well as a sealant, sealant.

You must understand that the penetration must withstand a certain load, including vibration, atmospheric pressure, and temperature changes. Different materials are used for the manufacture of penetrations. It is most often silicone, rubber. The advantage of these materials is that they are not afraid of corrosion, the scorching sun. They will fit snugly on the roof. Remember that this is one of the main barriers that will protect the rafter system. If you do not provide good protection, the tree will quickly rot.

Important! When selecting passage elements, consider the material of the roof itself and the size of the diameter of the object that you plan to display. When installing ventilation, it is important to properly arrange the passage of the shaft through the roof

Here you will need to install the passage node. There are several types of it. They have differences in installation. Each type has its own installation features.

When installing ventilation, it is important to properly arrange the passage of the shaft through the roof. Here you will need to install the passage node

There are several types of it. They have differences in installation. Each type has its own characteristics of the installation.

When choosing a node, consider the type of ventilation.

Air ducts are most often installed on reinforced concrete glasses. They are fixed with anchor bolts or nuts. Such nodes will carry air if the humidity is not higher than 60%.

Deflector application. The principle of its operation and design

The TsAGI ventilation deflector performs several functions: it enhances the exhaust in the ventilation system, prevents back draft, and protects the ventilation system from atmospheric precipitation. The principle of operation of the deflector is based on the laws of physics: air blows over the product from the outside, while inside the deflector the pressure drops below atmospheric pressure. Air masses tend to a zone of low pressure, i.e. draft is generated in the ventilation system and the air is drawn out. Most often, the deflector is used in ventilation systems with natural impulses.

The TsAGI deflector consists of the following parts:

1. A spigot that connects to a duct or passage assembly. It serves as an exhaust shaft.
2. Diffuser - an expanding cone that goes from the nozzle to the top of the deflector
3. Outer spigot/shell
4. Cap protecting ventilation from precipitation
5. Claws for attaching the cap

Conclusions and useful video on the topic

The video shows the difference in draft in ventilation pipes with and without a weather vane deflector:

The following video will acquaint you with the principles of operation and the arrangement of various deflectors:

This video shows the manufacturing process of the deflector:

The right choice, along with the competent installation of the ventilation fungus deflector, is important for creating a stable draft in the air exchange system. In addition, any of the ventilation hoods prevents precipitation, dust and foreign objects from entering the system channels.

The simplest Grigorovich deflector fungus can be made independently in the form of an umbrella.If you want to ensure stable traction both in calm and windy weather, then install a deflector on the ventilation pipe, or buy a ready-made factory-made ventilation fungus.

Tell us about how you assembled and / or installed the cap on the ventilation exhaust pipe with your own hands. Share technological subtleties and models of ventilation hoods known only to you. Please leave comments in the block form below, post photos on the topic of the article, ask questions.