The passage of a chimney through the roof: how to correctly route the pipe through the roof - nuances during installation

Objects that have a heating function from a boiler, stove or fireplace require normal exhaust of smoke to the outside, which is necessary to maintain the protection and safety of residents. Therefore, it is extremely important to know how to make a chimney pipe pass through the roof and roofing, taking into account all standards.

Basic Rules

If your home has heating, you will need to create optimal conditions for removing flue gases. There are several ways to remove the pipe depending on the installation location. Its choice is influenced by many factors, and the chimney can be installed:

• in the ridge itself;
• at a distance from him.

Each of the described methods has its own differences and features, but preference is given to installation according to the second option. To maintain the required draft force, the total height of the smoke channel must correspond to the limits of 5-10 m.

Modular smoke removal systems made of stainless steel - a modern option at an affordable cost

Today, the most optimal, affordable, safe and common type of chimneys are modular stainless steel pipes. Due to their technical characteristics and features, they allow you to create smoke routes of any configuration, length, inside or outside the building, and they also effectively and safely remove combustion products. Modular chimneys are easy and fairly quick to install; if assembled correctly, they can last for decades, and at the same time, they are affordable.

There are a number of rules and requirements that must be followed when installing a chimney in order to guarantee fire and operational safety of both the smoke exhaust route itself and the heating equipment. There are also certain rules for installing and installing a chimney on the roof. Let's look at them in detail in this article.

How to protect your roof from fire

To do this, you need to consider two points:

• Passage through walls and ceilings. Here it is necessary to use polyurethane foam with mineralite, since the outer pipe of the sandwich heats up to a temperature of 200*.
• When passing through the roof, roof trim and all other associated elements are required.

According to the standards, the minimum permissible distance between the chimney and load-bearing beams or rafters should be 130-250 mm. The inside of the structure is filled with heat-resistant material.

You can find passage diagrams in the Ferrum catalog in the “advertising and printing products” section of the website.

Sewerage

Why lead the sewer riser through the roof? The fact is that the air heats up when it comes into contact with wastewater, becomes saturated with moisture and rises.

If the risers are hermetically sealed, an unpleasant odor can penetrate into the kitchens, bathrooms on the upper floors, and in cases of leaky joints between plumbing and sewerage. The installation of ventilation systems is in many ways similar to the installation of ventilation.

Passage node

One option is to pass through the ridge.

But most often, the installation of a chimney pipe through the roof and roofing is carried out not through the ridge, but at a distance from it. According to SNiP requirements:

• The total length of the smoke channel must be at least 5 m. The only exceptions are houses that do not have attics, but subject to the presence of stable draft.
• The height of the chimney above the roof is at least 0.5 m.
• The chimney rises half a meter or more above the ridge. But if the horizontal distance between it and the ridge ridge does not exceed 105 cm.
• The mouth should be level with the ridge or higher, when the horizontal width is in the range of 1.5 - 3.0 m.
• The chimney outlet must be no lower than the line laid from the ridge towards the eaves overhang at a slope of 10º relative to the horizon.

The disadvantage is the need to compare the height of the chimney, which leads to additional costs. Professionals do not recommend doing it through the valley due to the fact that snow deposits often accumulate in such places, thereby compromising the waterproofing and causing leaks. There are also difficulties in organizing the box. Localizing the chimney in the lower section of the slope also has a significant disadvantage - the likelihood of damage when snow melts.

The installation work is also influenced by the material that forms the basis of the chimney pipe. This can be a metal, brick or ceramic base. Each of the listed options has a different combustion temperature, which you need to know when creating a project. Based on the pipe cross-section, the outlet can be shaped like a square, circle, rectangle or oval. Knowing how to properly vent a chimney through the roof, its installation is carried out in three successive stages, carried out by a specialized specialist:

1. Additional rafters are installed on the sides.
2. Laying horizontal beams at a distance identical to this hole (calculated according to SNiP and corresponds to the range of 140-250 mm).
3. Filling the inner surface of the box with non-flammable insulation material.

To prevent disruption of normal ventilation, it is recommended to install a separate ventilation system.

Elements used for terminals and sealing

Most often, chimneys have the shape of a circle; this complicates the making of holes in the roofing material, which can subsequently affect the tightness of the joints of the two systems: the roof and the chimney. In order to improve the quality of penetrations with further fastening to the roof structure and maintaining the required sealing quality, builders use ready-made penetrations, which differ in the form of manufacture and the method of creating elasticity at the joints. For convenience, there are several varieties of this element, which is also used when installing ventilation piping.

We recommend reading:

• How high above the roof should the chimney be?
• Review of modern chimneys;
• Ventilation passage through the roof

Smoke exhaust outlet through various types of roofing

Below are recommendations for installing a smoke exhaust duct depending on the roof material.

Tile roofing

In this option, to process the passage, professionals resort to the use of corrugated, self-adhesive, sheet aluminum or lead.

Exiting a pipe with a cross-section in the shape of a square or rectangle

If the smoke exhaust hole has a brick base, then due to non-standard dimensions, before removal, a small part of the covering sheets must be removed or cut to a larger size. To ensure waterproofing, elastic tapes with an adhesive base are used. They are glued by a specialist to the pipe base and roof sheathing. The upper edge is secured with a metal strip, and the existing connections are sealed with a sealed substance.

To prevent precipitation, it is recommended to install an additional tie.

Passage of a round chimney through the roof

This is achieved thanks to a special cap, which is responsible for the smoke exhaust hole. A small and even hole is made in the coating, according to the pipe dimensions. A master flush is put on it, and the existing connections are sealed with a sealed substance.

Consequences of poor installation

As a rule, the work of a stove maker or gas equipment installer does not include chimney installation services; the homeowner must ensure the passage of the chimney pipe through the roof independently. The imaginary simplicity of the task makes home craftsmen refuse the services of professional roofers. However, poor-quality pipe installation on the roof can have serious consequences:

1. Through an unsealed pipe passage, moisture seeps into the masonry, gradually destroying the brick chimney.
2. High humidity inside the chimney pipe stimulates the spread of mold and mildew. Spores of some types of fungus are dangerous to the human condition, so it is unsafe to use an infected tube. In advanced cases, both the chimney and the stove masonry must be replaced
3. The penetration of water into the passage of the chimney pipe through the roof reduces the thermal insulation properties of the insulation by half. Moreover, after the thermal insulation layer dries, its characteristics will never return to their previous level.
4. Even the rafter system suffers from poor-quality pipe removal through the roof, since moisture penetrating into it through a leaky passage leads to rot and destruction.
5. Gaps near the pipe passage disrupt the normal air circulation inside the attic, leading to increased energy losses and heating costs.

By the way, not only stove chimneys are brought to the roof; pipes from gas boilers and ventilation outlets are also placed there, for the installation of which the same methods are used.

Video material: tightness of a brick chimney through a metal tile

Corrugated roofing

This is a relevant material, often used in construction work. However, when using it, there is a risk of leakage, especially if technical rules are not followed. To prevent this outcome, it is recommended to place it in a vertical position. The roof hole is made with a grinder, but it is necessary to ensure that the resulting corrugated sheet does not have nicks or other irregularities.

How to remove a rectangular chimney pipe

In this situation, professionals recommend using galvanized sheet:

1. Cutting four strips for further mounting on each side.
2. Laying from the bottom edge to the cornice.
3. Attach the strips and bottom fastening to the sheathing.
4. Ensure tightness.

Exhaust of a chimney with a cross-section in the shape of a circle

In this case, installing a chimney through the roof requires rolled bitumen insulation or foil tape of the same name. After this, a penetration is installed, glued to the sheathing, and sealed with a heat-resistant sealant. If it is made of a rubber base, there is an increased risk of melting, so it is worth placing a clamp and gasket underneath that can withstand relatively high temperatures.

Video material: tightness of a pipe on a roof made of ondulin

Extraction through a soft roof

A distinctive feature of the material is that it belongs to the category of combustible building materials. Therefore, it is necessary to leave space between the coating and the hole for the chimney (approximately 13-25 mm). Waterproofing is done identically to other options. The difference is the use of a valley carpet or the installation of the coating itself on the pipe.

How to install a chimney through the roof

The work carried out by a specialist proceeds in several stages:

1. Determining the best localization of the passage site.
2. Installation of the box.
3. Cutting a hole in the slope.
4. Folding the roofing material outwards and the moisture insulation towards the inside.
5. Fixation.
6. Sealing the box and filling it with thermal insulation.
7. Creating a seal using sealants.

Passage through ondulin

The most important task is to fill the internal cavity with fire-resistant materials as much as possible. Insulation is provided by an apron that goes under the roof. For this purpose, it is worth taking a closer look and purchasing self-adhesive tape “Onduflesh”.

Extraction of a smoke channel in a constructed roof by a master

1. Choosing a suitable location.
2. Forming a box from beams.
3. Creating a hole in the roof.
4. Filling the box with non-flammable material.
5. Sealing joints with a sealant.

Round pipe

The difference between installation work is the need to use special cutting. The professional conclusion is as follows:

1. Arrangement of the box.
2. Cutting a hole for the chimney.
3. Fastening an iron sheet or installing a ready-made part.

Elastic penetrations

Since it is problematic to install a chimney through the roof without professional help, it is important to pay due attention to the selection of each detail.

Distinctive characteristics are:

• Resistance to adverse weather conditions.
• UV resistant.
• Flexibility.
• Tight fit.
• Aesthetics.

Hard penetrations

There are two main types:

• One-piece - inserted into the upper edge of the chimney, after which a cap or cone is put on top.
• Detachable - its upper part is put on the chimney, and a sealed substance is applied along the edges; strong fixation is ensured with the help of a clamp.

Chimney height and placement

All calculations performed are based on the requirements of SNiP 41-01-2003 and SP (building rules) 7.13130.2009, as well as on recommendations received from manufacturers of heating devices.

When constructing a flat roof, it is assumed to leave a margin of at least 50 cm. For a pitched roof, the following rules from the craftsmen apply, based on the distance between the chimney and the ridge and their location:

• Up to one and a half meters. In this case, the height of the pipe must be at least 50 cm (relative to the last or enclosing parapet).
• Within 1.5-3 meters. Here the height cannot be lower than the ridge.
• If you want to place elements further than 3 meters, then the minimum height will be determined by drawing a line at an angle of 10 degrees relative to the horizon.

Parameters for proper operation of the device

A properly installed chimney creates natural draft and removes combustion products through a channel, preventing them from entering the room. Sometimes you can even evaluate the operation of a chimney visually - by the presence of smoke in the room or the color of the flame. Excessive draft is determined by a white flame and a characteristic hum, while a bright orange flame indicates insufficient draft. A special device, an anemometer, will help you take more accurate measurements.

Related article: How to treat rafters and roof sheathing

If traction needs to be strengthened, you can use one of the following methods:

1. Install the deflector. However, it must be taken into account that deflectors improve traction only in the presence of strong wind.
2. Install a special umbrella on the chimney. Using a sensor located under the hood, the umbrella regulates the combustion temperature.
3. Increase the height of the pipe.
4. Use a turbine nozzle.

Fire safety

Some layers of the roofing pie and the wooden rafter system cannot withstand high temperatures, so the likelihood of fire increases. To eliminate this risk, it is necessary to use a special box along the perimeter of the roof opening.

Pipe waterproofing

Protection from moisture is also an important step that should not be skipped when arranging the passage.

Basic installation work

The box is mounted from timber, located level with the sheathing. Vapor and waterproofing is fixed along its edges. To do this, a cross-shaped cut is made in the canvas and a triangle-shaped piece of material is turned into the inner surface. To ensure fixation, you need to stock up on nails with a wide head or construction staples. You will also need sealants and adhesive tape.

Fixing a roof leak near a pipe

To do this, a drainage gutter must be laid. And the hole itself is covered with internal and decorative aprons.

Insulation with bitumen tape

Provides a high level of sealing of any type of surface. It completely eliminates the negative effects of moisture, as it is characterized by significant strength.

Elements used for output and sealing

• The box is galvanized.
• Ceiling overhead sheet.
• Stainless steel clamps become.

Provided that the technical rules are followed correctly, the passage of the chimney through the roof and roofing is characterized by good thermal insulation, which is achieved by filling the internal cavity with basalt wool or other heat-resistant materials. If possible, it is better to leave a small space with air (5-7 cm) between the insulation and the smoke conductor. If penetrations are involved in the installation of the structure, then you should select the required part taking into account the material that makes up the base.

What are the consequences of violating the installation rules?

If the chimney box on the roof was installed improperly, this can lead to the following problems:

1. Gradual destruction of the chimney.
2. High level of heat loss.
3. Formation and deepening of cracks in the structure.
4. Disruption of the gas circulation process.
5. Ingress of moisture, which leads to destruction of the pipe and duct.
6. The presence of moisture can lead to rotting of wooden parts and the formation of fungus.

Therefore, it is important to install the pipe and the duct for it in accordance with the technological requirements.