A practical chimney made of sandwich pipes has many advantages. It is a lightweight, reliable, safe and aesthetic option that is ideal for private buildings. It consists of individual elements, so it does not cause any problems at the assembly stages. Before installation, it will be useful to study its structure from the inside and from the outside, evaluate the pros and cons, get acquainted with acceptable standards and sizes, and also learn about the available installation methods.
Chimney device from a sandwich pipe
The chimney sandwich looks like an element of a double-circuit type in the form of a cylinder, which consists of two or three sections of pipes with a length of not more than 1 meter. During installation, these pipes are charged one into another according to the example of the designer. The contours of such flues are externally made of rolled pipe, between which they lay material for thermal insulation. Most often it is mineral wool, basalt fiber or vermiculite, these components do not allow the air duct to cool and prevent the accumulation of condensate from the inside. Internal circuits are most often made of steel with a heat-resistant effect, which is resistant to corrosion.
The chimney made of sandwich pipes can be internal or external, taking into account the location of the boiler or furnace, the amount of free space and structural details of the element itself. The outdoor version is a smoke exhaust system that connects the exhaust pipe to a pipe passing through the wall into the street. To ensure optimal traction, the pipe for the chimney in height must be made not lower than the minimum level of the ridge or above it. The horizontal section length cannot be more than 1 meter, the distance from the extreme corner of the roof should be at least 0.5 meters. Installation of a chimney from a sandwich pipe outside requires the installation of a separate device for insulation.
The internal chimney system has a vertical structure, it is located inside the house and is led outside through the roof. The connection of elements is carried out outside the floors of the attic and between floors in order to avoid the formation of barriers when it is necessary to check the tightness. In sections of the aisle, the structure must be additionally protected from the influence of high temperatures with the help of straight pipe elements and a passage for the roof. Seals with roofing can be sealed using special cutting.
Mounting the pipe inside vertically increases the stability of the draft, such chimneys are simpler and do not cause difficulties in the installation process.
Advantages and disadvantages
Before you begin installing a chimney from a sandwich pipe through the roof, you need to familiarize yourself with all the advantages and disadvantages of this design. The list of main advantages includes:
- lack of problems during installation by internal or external method;
- good sound insulation properties due to the three-layer structure of the pipe walls;
- compatibility with all types of heating appliances;
- esthetic appearance, versatility and low weight of the structure;
- optimal heat-shielding properties;
- increased fire safety;
- smoothness of the inner surface of the pipes, almost not subject to soot accumulation;
- long term of operation.
The arrangement of ducts from the sandwich elements has its drawbacks. The loss of tightness provokes the reaction of the material of the constituent elements to temperature changes.Consumers also note the high price of this type of system.
It is necessary to choose the thickness of the heat insulator taking into account the temperature of the exhaust gases. If boilers of low or medium power are installed in the room, capable of heating up to 250 degrees, an insulation layer with a density of up to 30 mm is suitable for them. In more powerful gas and liquid fuel installations, this value should not exceed 50 mm. Solid fuel coal units in which smoke can heat up to 1000 degrees should be equipped with a heat insulator with a thickness of not more than 100 mm.
Chimney Sandwich Choice
To carry out the installation of the chimney from any sandwich pipes according to the rules, first of all you need to decide on the choice of the main material, as well as auxiliary elements and components.
Materials used
The type of material is selected taking into account the specific device for heating and the type of fuel. For modern chimneys, high-strength steel or ferrous metal is most often chosen. The list of the most reliable steel alloys includes stainless material stabilized with titanium or molybdenum of AISI 321 and 316 categories, as well as heat-resistant steel of AISI 304 type. Metal 321 is unstable to corrosion and is suitable only for appliances operating on wood, the analogue with number 316 is intended for installations on gas or diesel fuel.
Heat-resistant steel contains chromium in combination with nickel, which are insensitive to elevated temperatures and oxidized environments. Ferrous metal is also suitable for chimney pipes. Since it is able to burn and oxidize, it is additionally covered with a layer of special enamel. Enamel tubes can be used for a long time when heated to 400 degrees and with a rapid increase to 750 degrees. Combined sandwich chimneys are also in demand, these are more economical analogues, consisting of double pipes made of different materials.
When choosing combined parts, you need to look at the materials from which they are made. Pipes of the internal type must be made of durable stainless steel, only in this case they will last as long as possible.
Necessary Details
In addition to the chimney, for its installation, it is necessary to purchase additional parts that will become elements of the entire system. This includes straight tube elements up to one meter long and with a diameter of up to 80-600 mm, as well as knees and tees designed to be led through the wall to the street or to bypass the beams or rafters. In addition to these parts, buy branch pipes for insulation of pipes from interfloor partitions and a metal cone for cutting the roof.
Prices
The assembly of the chimney can be carried out independently or by specialists. Although the installation of the structure is not difficult, problems may arise at some stages of the assembly, and only professionals can fix it. The price of installation and assembly work will depend on the length of the channel, the type of placement, as well as the number of floors. Usually it varies between 1700-2000 rubles per meter.
Installation of a chimney from a sandwich pipe
Before mounting the chimney, you need to select the main part and additional materials, depending on the type of heating device. For units that run on gas fuel, the most budgetary models are suitable, if we are talking about a traditional or sauna type furnace, it is worth giving preference to a high-quality and more expensive system. First, the duct is connected to the boiler, then it is led out through the ceiling to the roof.
To the boiler
A heating boiler with a horizontal outlet pipe on the monotube side can be fixed with a mono-tee, supplemented with a plug with a condensate collector. The exit surface to the center from the inside is covered with a sealed layer with a heat-resistant effect.After the tee is tightly put on the chimney, it is pushed to the end and fixed in the connecting part with the bracket with a clamp according to the rules. It is important to check the verticality of any axis of the tee in advance, only after that it is allowed to fix it to the wall surface with anchors or dowels.
Through the ceiling and roof
With a phased installation of the duct, the section for removing the tube will need to be shifted to one side in the direction from the ridge. If it passes through it, the installation of the passage unit will disrupt the structure of the ridge beam and rafters. The sandwich pipe is installed through the ceiling in accordance with all building codes and fire safety regulations.
After choosing a suitable place, you need to make a hole according to preliminary marking. Then it is attached to the ends with the help of nails or self-tapping screws and the edges are encased with a heat-resistant insulator. You need to assemble the ceiling passage assembly according to the scheme, the box itself is attached to the ceiling using self-tapping screws. Next, the sandwich structure extends through the node and is fixed mainly vertically.
The free space inside the box must be filled with expanded clay or mineral wool for thermal insulation. At the final stage, the hole is closed with a stainless steel sheet.
The correct design of the output to the roof
Installation of a chimney from a sandwich pipe through any roof must be carried out according to the rules so that the part is installed at an acceptable height and provides good traction. In this case, the removal of combustion products will be most effective regardless of the weather. The total length of the entire system should not exceed 5 meters; deviating from this value can only be done in a smaller direction. If there is a flat roof, the height of the tube in the standard version cannot be more than 0.5 meters. During the installation of the chimney communication, the placement of beams for floors and the roof truss system is taken into account.
DIY assembly instructions
They begin to mount the system from the bottom up with the installation of an adapter or a single-walled steel tube with a length of at least half a meter. It must be placed in smoke, that is, put on the pipe for heating from above and close the joints with heat-resistant sealant. The remaining elements will be placed on the condensate in order to prevent its leakage and damage to the insulating layer. All fastenings are supplemented with couplings; a clamp is placed near all joints to help attach the system to the wall surface. The surfaces of the chimney can become very hot despite the insulation layer, therefore they should not be placed near materials subject to fire.
When the tube exits through the passage, its tightness may be impaired. To strengthen, protect from parts that may catch fire, and eliminate possible leaks, special rats in the form of cones and silicone seals are used. When placing the tube, a distance is allocated to materials subject to fire, which must be at least 37 cm. To protect the roof from water, an apron is mounted in the upper part of the rat and its edges are brought under the roof covering. The height of the chimney pipe will depend on the distance between its beginning and the ridge. The upper part of the element should rise above the roof surface by 1.5 meters in the presence of buildings located nearby.
When using combustible materials for the roof, a spark arrestor is placed inside the duct. The chimney system must be supplemented with the head part in the form of a cone, which can be additionally protected by a deflector or other device.
