Additional elements for roofing are represented, in most cases, by products made of metal or modern plastic.
Such elements are used in areas of roof joints, and also cover joints and ends, which gives the structure additional strength and protects it from damaging moisture.
The category of additional elements also includes smoke umbrellas , which are an integral part of both steel chimneys and classic brick chimney systems.
Chimney umbrella - what is it and why is it needed?
A protective umbrella is the top of a cap, which in appearance can be a cone, a pyramid, a semicircle or other, more complex structures and shapes.
The functions of the umbrella, which is installed on the chimney pipe, are as follows:
- prevents atmospheric water or snow from entering the chimney . A side effect of heavy rainfall is the accumulation of a large amount of moisture in the chimney pipe, causing a decrease in natural air draft;
- equipping a brick chimney with an umbrella prevents destruction of the material , and the presence of special grooves allows for the timely removal of all accumulating condensate;
- the presence of a chimney umbrella does not allow insects , animals and birds, leaves and other objects blown by gusts of wind to enter the chimney.
Chimney umbrellas
IMPORTANT!
You also need to remember that when using an umbrella, traction significantly improves, and the standard indicators for increasing this level of this parameter are approximately a third of the total volume.
The umbrella does not interfere with the emission of smoke with combustion products only if such a device is chosen correctly . For example, in areas with heavy snowfall, it is advisable to use additional elements with a large angle of inclination for unimpeded melting of the snow mass.
Pros and cons of a house chimney umbrella
The main advantages of the hood are:
- Reduces the likelihood of the draft overturning by preventing wind flow from the street.
- Protection from debris and precipitation.
- The net will prevent birds from building nests.
- Increasing the service life of a brick pipe.
- Appearance.
Attention ! You should not believe the information disseminated in advertising of such devices. The cap cannot increase the efficiency of the boiler or increase the draft in the pipe.
Formed icicles on the canopies Source obustroeno.com
See also: Catalog of companies that specialize in the design, installation and repair of roofs
But there are some reasons that do not allow caps to be used everywhere. The main disadvantage is the creation of aerodynamic drag. The fungus located directly above the pipe will prevent gases from escaping. Subsequently, this will lead to a decrease in traction.
The second disadvantage of the design is the possibility of the formation of icicles. Due to the low temperature of the gases, up to 120 degrees Celsius, water vapor, upon reaching the hood, quickly cools and forms ice, which prevents carbon monoxide from escaping through the pipe from the house.
What is the difference between an umbrella and a weather vane, cap, head and chimney?
The chimney, weather vane, cap, umbrella and cap are quite simple and time-tested protective structures for air outlets on the roof . Steel, copper, aluminum, plastic and titanium-zinc additional elements, when properly installed, can be used for ten and sometimes more years, providing comfortable and safe living:
- caps - the general name of elements that prevent precipitation and foreign objects from entering the chimney, as well as carrying a decorative load;
- chimneys - rectangular or square decorative caps designed for arranging chimney and ventilation pipes;
- umbrellas - are represented by caps that are simple in design and designed for round or square pipes;
- deflectors - caps on round pipes, characterized by a rather complex internal design to increase traction.
The category of complex structures also includes weather vanes - rotating caps that direct the escaping smoke exclusively in one direction, depending on the direction of the wind.
NOTE!
Umbrellas are used to equip a round or square head, but modern manufacturers, in addition to functionality, take into account ease of use, including adding a smoke dissipator to the lid.
Umbrella or deflector
Building codes indicate that installing baffles on pipes from gas boilers is strictly prohibited. The reason is the possible formation of ice on horizontal sections of the pipe, which will lead to deterioration in traction. The deflector is an aggravating factor due to which the freezing process will occur faster. For exits from gas boilers, only primitive umbrellas can be used to prevent the entry of debris and precipitation.
A weather vane with an interesting design that can destroy the chimney Source kaminych.rf
The shape of the installed cap depends on the shape of the chimney. If the house uses a sandwich chimney system, then the chimneys are equipped with a special skirt to ensure thermal insulation. In brick pipes, it is enough to equip the cap with a base to protect the bricks from the effects of precipitation. Deflectors are allowed for installation on metal pipes of boilers that operate on solid fuel.
It is worth abandoning weather vanes. Such structures are constantly exposed to wind pressure, which creates vibration that gradually destroys the brick pipes. As a result, not only the cap, but also the chimney itself quickly wears out.
Types of protection for the chimney and ventilation pipe
The classification of umbrella types is determined by their shape, purpose, and materials used in their manufacture.
Depending on the shape, the most widespread are standard designs that replicate the appearance of a hipped roof, as well as varieties in the form of a mushroom cap.
Varieties can be represented by drips and drains designed to collect and further remove all flowing moisture, as well as prevent it from getting inside.
To make a mushroom or umbrella, various non-ferrous or ferrous metals can be used, but galvanized durable steel is most often used.
Varieties of smoke umbrellas also include deflectors, which act as a very effective spark arrestor.
The appearance of the structure and the materials for the manufacture of the chimney “fungus” do not have a significant impact on the functionality, so when choosing, consumers should focus on finances and personal preferences in decor.
Standardized products
- Chinese weather vane, having concave and diverging sheets in all directions. Rounded edges give the design lightness and elegance. Such caps on the chimney pipe serve as decoration for the radius roof. Download drawing
. © kolpak.ru - Standard weather vane. This design has a second bottom. It is installed on the chimney, as well as on the vertical ducts of fireplaces. This type of part is considered the most popular. The standard weather vane is suitable for installation on any building. Download drawing
. © kolpak.ru - Cap with bars and a 4-slope roof. This element belongs to the most modern European-style designs. Download drawing
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© kolpak.ru
How to choose a chimney umbrella
When choosing an umbrella designed for chimneys, as well as ventilation outlets, you need to pay attention to the quality of the material, and also take into account the diameter of the outlet and the purchased element.
The system of protection from external adverse factors must be thought out at the design stage of the smoke exhaust, with mandatory consideration of all design features.
Umbrella with protective mesh
Basic installation rules
The installation of a smoke hood directly depends on the design features of the additional element and chimney pipe, as well as the material used in manufacturing. Based on standard rectangular sheet steel, the easiest way to create a tetrahedral pyramidal umbrella is by bending the sheet of material a couple of times in a diagonal direction.
This option is traditional for arranging chimney pipes on hipped roofs, but to attach racks and further installation it is necessary to use additional elements in the form of corners, as well as drill holes.
Wind vane installation
Simple vaulted umbrellas with a minimum number of folds and cuts have a less complex design. Fixing such a smoke umbrella on an oval chimney pipe is carried out due to the presence of racks bent from sheet steel of sufficient thickness or made using standard metal corners.
Regardless of the manufacturing method, racks can be fixed in several ways:
- on metal and asbestos chimneys, you can use a metal clamp or make a regular wire frame yourself;
- the wire for the frame base should be as strong and reliable as possible;
- mounting holes are drilled in the racks;
- the outlet parts of the twisted wire frame are passed through the mounting holes on the racks and twisted until the smoke umbrella is completely fixed.
On brick chimneys, even standard galvanized nails of sufficient length, implanted directly into the masonry, can be used to fix the umbrella. However, as practice shows, it is best to drill holes in the brickwork using pre-drilled holes in the umbrella posts , and then secure the cap to the chimney pipe with steel pins or galvanized screws.
Umbrella installation
In this case, if necessary, you can quickly and with minimal effort dismantle the umbrella yourself for cleaning or replacement.
CAREFULLY!
It should be remembered that when using a gas system as an autonomous heating system, it is strictly not recommended to install an umbrella on the chimney pipe.
Do I need a cap?
The regulations governing the safety of the installation and use of chimney umbrellas vary from country to country. If in Europe the legislation strictly prohibits the installation of nozzles on chimneys, while there is no such restriction for ventilation, then the legislation of the Russian Federation has a nuance. The wording is vague, which is why there is no direct prohibition.
Obviously, the existing disadvantages must be taken into account, so when installing the cap the following should be taken into account:
- If the efficiency of a round steel pipe is less than 85%, then you should not install a mushroom-shaped nozzle. As a replacement, you need to use a cone nozzle.
- When using a heat generator with high efficiency, you can install a roof-shaped nozzle.
- For stoves and TT boilers, umbrellas are a suitable option. To protect the nozzle from gases, a stainless steel plate is installed.
- If the gas outlet is realized using side vents, then gable or hip hoods should be used.
Cone-shaped cap Source 1-line.pro
You need to choose the type of chimney hood to install based on the type of pipe. Conventional mushrooms are suitable for ventilation, and cone-shaped nozzles are suitable for gas ones.
How to make an umbrella for a chimney with your own hands
Before manufacturing, the diameter of the chimney must be measured, and the step-by-step technology for manufacturing such a structure is as follows:
- cut a tin strip 70-80mm wide and long depending on the diameter of the chimney pipe, adding a small margin for fastening;
- Use a caliper to draw strips with a 10mm indentation from the edge of the tin strip;
- punch the rails with a hammer in accordance with the marked stripes , which will allow you to easily and evenly bend the workpiece;
- make four parts according to the strip marks, tap, make a right angle, wrap and finally punch with a hammer;
- prepare a cardboard round pattern , the diameter of which exceeds the size of the chimney pipe by 150mm;
- cut out a tin circle for the umbrella in accordance with the prepared pattern and cut out an angle that allows you to assemble it in the shape of a cone.
DIY umbrellas
The finished umbrella must be riveted in a couple of places, after which three reinforcement strips or so-called racks must be attached to the structure.
IMPORTANT!
The easiest way to improve the appearance of the finished structure is to beautifully design the edges . For this purpose, you can make cuts in the metal along the edges and slightly bend the resulting “petals” or bend the cut edges in a wave-like manner.
