The chimney is part of a private house heating system designed to remove fuel combustion products from the premises. If you have fireplaces, gas and solid-fuel boilers, columns, or furnaces in the house, you will definitely need to install a chimney. More reliable and practical metal chimneys have replaced traditional brick chimneys in recent years.
The chimney must be properly designed and installed. It should be operated according to the rules. Otherwise, it is possible to smoke premises, toxic poisoning, and even fire. To prevent this from happening, it is worth understanding how the chimney is arranged and what requirements are imposed on its installation.
At first glance, it seems possible to remove combustion products from the house by any pipe. But it’s not. Let’s start with the fact that the chimney always sooner or later accumulates soot, which can catch fire. The pipe must have the correct diameter and height, with a smooth inner surface, then the accumulation of soot will be a rare occurrence.
The pipe is usually not straight along the entire length, it needs to be inscribed in the house’s architecture, so in modern conditions, the chimney is assembled from the modules. Knees and branches connect the modules. To install the chimney, you will need a fastener. At the exit, the pipe is covered with a headband to protect against precipitation. For aesthetic reasons, metal pipes are often enclosed in casings of various materials combined with the roof.
What a chimney should be
The chimney must comply with building and fire regulations and the chosen heating system. If you change the heating boiler, the chimney, as a rule, also has to change.
The height of the chimney
The pipe should be high enough to ensure the removal of combustible gases at a safe distance from the roof. The minimum height of the pipe is 50 cm. Such low pipes are acceptable only for flat roofs without protrusions. If the roof has a more complex configuration, the calculation of the height of the pipe will depend on the distance to the protruding parts. If the protruding parts are located at a distance of 1.5-3 m from the pipe, the pipe should be no lower than them. If they are closer, the height of the pipe should exceed their height by at least 50 cm.
The diameter of the chimney
The diameter of the pipe is calculated according to the power of the heating boiler. With a capacity of less than 3.5 kW, the chimney should be at least 80 mm in diameter, at 3.5-5.2 kW – at least 95 mm, with more power – from 110 mm.
Which pipe to choose for the chimney?
Currently, three main types of chimneys are used – steel, coaxial and sandwich chimney. Brick chimneys are considered obsolete: they lose in durability, quickly clog, suffer from condensation. They serve no more than five years, after which the masonry needs to be updated. This is an expensive and inconvenient option.
Steel chimneys are made of single-layer steel modules, are the simplest and cheapest, but lose fire safety parameters because they are very heated.
In wooden houses, it is better to use sandwich chimneys, consisting of steel pipes embedded in each other, the gap between which is filled with insulation material. Due to insulation, the external pipe is protected from overheating. When calculating such a chimney, the diameter of the inner pipe is oriented.
Coaxial chimneys are also made of pipes embedded in each other but without insulation. The air layer provides thermal insulating properties. The flow of oxygen through the gap between the pipes supports the burning of fuel in the boiler. The inner tube is held in a coaxial chimney using metal jumpers. The coaxial chimney can be displayed outside through the wall, and this seriously simplifies its installation and positively affects the cost. Coaxial chimneys are mainly used for gas heating.
Make a chimney with your own hands or order a professional installation turnkey?
You can make a chimney yourself if you have the necessary building skills and make a correct calculation. Techniques can always be explored online. However, in the absence of proper experience, this event may be a failure, and you will have to pay twice. Since it is necessary to install the chimney in compliance with the existing rules and regulations, it is better to entrust this issue to professionals for whom the correct installation of chimneys is part of the daily working practice. To overpay, contact a reputable company with a good reputation, where they will not inflate prices.