Height of the chimney above the roof: chimney requirements, inspection and operation

The construction and operation of chimneys are construction stages that should be given special attention. This article tells about the requirements for chimneys (for example, the height of the chimney above the roof), how to comply with them and properly install them.

The correct installation and operation of the chimney directly affects how efficiently and safely the equipment that heats the house will work. The arrangement of chimney systems must be carried out by specialists with sufficient qualifications, observing all fire safety requirements.

For solid fuel boilers, it is recommended to use steel with a thickness of 1 mm, and for heating devices operating on liquid and gaseous fuels, use the most corrosion-resistant steel grades.

If there are chimneys passing outside the building or through unheated rooms, such sections of the chimney system should be thermally insulated, preventing moisture condensation inside the chimney itself.

Chimney Requirements

The following requirements apply to chimneys:

• Combustion products must be completely discharged into the atmosphere through smoke channels;

  

• Each stove and each heating appliance must, in most cases, be equipped with a separate chimney;
• The cross-sectional area of ​​the chimney pipe must satisfy the power of the heater, and the cross-sectional areas of the round chimney ducts must not be less than the area of ​​the rectangular ducts;
• For the manufacture of metal pipes, special high-quality steel with increased resistance to corrosion should be used;
• Cleaning of soot deposits accumulating at the base of the chimney is carried out using pockets, the depth of which is 25 cm;
• The chimney must have at least three bends. For each bend, the radius of curvature must be no less than the diameter of the pipe;
• The height of the chimney pipes must be at least 5 meters for the entire length, in order to create draft and provide the required clearance. The height of the exhaust ventilation ducts located near the chimneys should be equal to the height of these pipes.

The height of the pipe above the roof should have the following values, depending on the conditions:

• Above flat roofs – at least 50 cm;
• Above the parapet or ridge of the roof, when the distance from the ridge to the pipe is less than 1.5 m - at least 50 cm;
• If the chimney is located at a distance of 1.5-3 m from the ridge - at the level of the parapet or ridge or higher;
• If the chimney is located further than 3 m from the ridge - on the line from roof ridge at an angle to the horizon of 10 °, or above it;

Important: if the chimney rises more than one and a half meters above the roof, or it is impossible to securely fasten it to the supporting elements, extension clamps or a structure that performs the function of a mast should be used.

The elements are mounted, from the bottom up, starting from the heating apparatus. During installation, the inner pipe is inserted into the previous one, and the outer one is put on it..

In this case, it is necessary to use a sealant, the working temperature of which is at least 1000 °, which provides the most effective sealing.

Joints of pipes with other elements (tees, bends, etc.) should be located outside the ceiling slabs and fastened with clamps. Wall brackets are installed on every two meters of the chimney, a support bracket is installed on the tee.

For fastening elements of chimney systems to various building structures, consoles and support platforms are used, located no further than five meters from each other.

Important: when attaching the connecting pipes, the possibility of deflection should not be allowed.

When installing smoke channels, it is important to ensure that they do not come into contact with electrical wiring, gas pipelines and other communications. When conducting smoke channels through the roof and ceilings, an indent from the crate and other elements should be left to ensure proper fire safety.

Structures made of combustible materials (walls, beams, floors, etc.) adjacent to the chimney channels are protected from fire by means of indents or sections made of non-combustible material.

The dimensions of such cuts depend on the thickness of the walls of the thermal insulation:

• If combustible materials are used in the building structure - 500 mm;
• For protected structures - 380 mm.

Important: the structure is protected if it is sewn up with a sheet of metal on asbestos cardboard, the thickness of which is 8 mm, or covered with plaster on a metal mesh (thickness - 25 mm).

The heating of the combustible structures located near it by the smoke channel should not exceed 50 °. Cutting should exceed the thickness of floors or ceilings by 70 millimeters.

The distance between smoke channels and structures made of flammable materials must be at least 260 mm, taking into account the security of these structures.

There must be no horizontal sections in the chimney that are longer than 1 meter. If the roof of the building is made of combustible materials, it is necessary to provide spark traps in the chimney made of metal mesh, the openings of which do not exceed 5x5 mm.

Check and operation

After roof mounting is completed, a control furnace is performed to check the tightness of the joints and the absence of heating of structures made of combustible materials. During the first use of the chimney, a specific smell and slight smoke may appear, which is associated with the evaporation of sealant residues and oil from the metal.

During the operation of modular chimney systems, it is prohibited:

• Drying clothes, shoes and other items on chimney elements;
• Soot removal by burning;
• Operation in a manner not provided for by the manual;
• The use of chlorine and its compounds;
• Placement of flammable products and objects near the chimney;
• Use of household chemicals, construction debris, paints and varnishes, etc., as well as coal as fuel;

The chimney should be cleaned at least twice during the heating season. Lack of cleaning can lead to the accumulation of combustion residues such as tar and soot, which coke and subsequently ignite.

The design of the chimney also does not provide for operation at high temperatures inside the pipe, which can lead to damage to the chimney and a fire hazard.

Proper installation and operation of chimneys not only ensure the most efficient operation of heating equipment, but also minimize the risk of fire, which is very important when building a house and living in it.

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