Do-it-yourself ventilated ridge for a soft roof. Soft roof ventilation - why it is necessary, main functions and elements. Auxiliary ridge ventilation

When I am just starting the installation of the truss system, I pay great attention to ventilation. At the same time, some passages and additional elements are created every now and then in order to ensure good air permeability. Is roof ventilation really so important that we will spend extra money on its arrangement? Such a question, though not often, but still asked by customers. Therefore, I will now tell you everything about ventilation and its features during construction.

No matter how complex or simple your roof is, it needs ventilation ducts. In fact, they are created only in order to protect the insulation boards, the truss system and metal structures from condensed moisture.

What can ordinary moisture do, because I have everything wooden crafts worked out with antiseptics, and the insulation boards are protected by waterproofing? I'm just tired of answering such a question, but since there are people who care about this issue, I'll tell you. No antiseptic and no waterproofing can protect 100% from moisture. Water always finds its way. Therefore, your roof will cease to be for you in less than ten years. reliable protection and will need new renovation. Do you need it? Therefore, in this article I want to tell you how to bring ventilation to the roof and not be a fool.

• Causes of moisture
• Ventilation methods
• Products. What is it?

So where does the water come from in fact closed space? Not out of thin air! Just from him. After all, since the time of school, you must remember that in an ordinary residential area, the percentage of moisture content in the air should be 40-60%. Pay attention to these numbers, they are indicated for the room, and we are talking about a roofing system, which is essentially a street.

Causes of condensation:

• High humidity (fogs, rains)
• High temperature in the living room (if the plane of the ceiling of this room is an attic on the other side, then condensation is sure to form there due to temperature differences. The solution to this problem can be the exit of ventilation under the roof from this very room)
• Ventilation system not organized

I hope that you understand the importance of arranging such a system and are now wondering how to properly implement it. The most common type is the withdrawal of ventilation to the roof through holes, gaps in the ridge and along the perimeter of the roof overhangs.

Let's take a closer look at this method.

Wind currents, temperature difference drive air masses under the roof overhangs, they pass their way through the gaps, which, as a rule, are created between the waterproofing layers and the insulation boards, and then are removed through the holes in the ridge. Such a gap in some way depends on the type of roof, it is often made 5 cm, and with a roof slope of less than 12 °, it is better to make a gap a little more than 8 cm somewhere.

In addition to creating natural ventilation umbrellas are purchased for roof ventilation, fungi, or exhaust vents are created not under the ridge, but on the slopes using some elements. For example, the ventilation of a metal roof can be arranged using special tiles with holes, which are sold at any hardware store.

Dormer windows

As a child, I mistook dormer windows on roof slopes for ordinary ones, and all the time I thought about the people who live on the roof, but I never saw them and imagined that they simply left too soon and returned too late. Having matured and studying the profession of a builder, only then did I understand what they were intended for.

Dormer windows on slopes - the most old way ventilation, which still exists. But he cannot be separate part system, only its complement. By the way, if you have one such window, then there will be little benefit from it, unventilated zones will appear around it, which will cause decay. Therefore, when mounting a dormer window, make sure that there are several of them.

The selection of sizes and localization of the dormer window on the slope should be known at an early stage in the construction of the truss system. It is worth considering that the location of windows closer than 1m to each other is not advisable, ugly and expensive. Distribute the windows evenly throughout the roof parameter and reduce their number to the optimal minimum so as not to complicate the process of assembling the truss system for yourself.

Forced ventilation

In exceptional cases, when the volume of the attic space has big numbers, may be needed additional ways ventilation, the so-called forced. Turbines and deflectors are construction elements specially designed for these needs. They have the ability to draw air from the under-roof space, thereby ensuring the passage of air masses.

IMPORTANT: With a slight slope of the roof slope, do not create wide openings for natural ventilation. It is better to use pipes instead, the length of which will be higher than the snow cover.

From what has been read above, the main types of ventilation can be distinguished:

• Natural ventilation (gaps, channels)
• Forced ventilation (turbines, deflectors)
• Dormer windows
• Installation of fungi, umbrellas, aerators

Ventilation of insulation layers

If you are at least a little versed in the roof, then you probably know the expression "pie". This is the name of the layer where the insulation boards are located between the layers of waterproofing. The insulation is the thickest in the roofing pie and, in general, heat-saving properties lie on it. By the way, the climatic region just affects this thickness and can change the value by 10-15cm. High-quality work when laying these layers will allow you to maintain the indoor temperature at the optimum level for you, despite the bad weather outside the window.

Any fibrous type material will absorb moisture, and if it is “saturated” with it, it will lose its properties and collapse. This is what happens to your insulation when water, which is an excellent conductor of heat, simply displaces air from the material.

IMPORTANT: The ingress of 5% moisture into the insulation boards reduces them useful qualities by 50%.

As a rule, the construction "pie" implies the protection of thermal insulation plates on both sides with waterproofing, but this is often not enough. The appearance of condensed moisture on its surface is inevitable.

But is it only on the surface? No.

Even inside the cake, channels for air exchange should be created. To do this, at the end of the laying of the last layer of waterproofing, small wooden blocks, which will lift the film and thereby create the necessary gap for the free movement of air masses.

Products. What is it?

I talked a lot about some kind of holes, gaps, and by the way they have a building term - air vents.

They are:

• Cornice
• Skate

If your choice fell on the first ones, then I can advise you to make them around the entire perimeter of the roof where there are cornice overhangs. Just leave gaps of 2-3 cm between the roof and the wall, but if you already have several types of ventilation, then spot vents can be arranged. Their dimensions directly depend on the angle of inclination of the slope. If the roof is almost flat and has a slope of less than 12 °, then the gap is 3 cm, and if more than 12 ° - 1 cm.

The vents in the ridge can also be along the entire length of the ridge or local (point). The latter should be arranged in such a way that the distance between them is in the range of 6 to 8 meters. For example, roof ridge ventilation under natural tiles done in such a way that the second row from it is laid special tiles. They already have holes and they are called - ridge. The same work will be done even if you do ventilation ducts under another material, for example, a metal tile.

The manufacturer of roofing materials, as a rule, produces all necessary elements to build a good ventilation system. They can be matched to any coloring and roof design, creating a beautiful architectural look.

There are times when it is necessary to provide good ventilation and keep the room warm. Then comes the time of calculations, and I resort to simple and effective methods. 10-15% - this is how much the area of ​​​​exhaust air should be larger than the supply air. And the length of the gaps themselves and their number can be distributed by yourself, but it must be taken into account that for 200m2 of attic space there should be at least 40cm2 of gaps with ventilation.

Ventilation through the roof in a private house by means of aerators

All the same pipes are called aerators, only slightly with big bells and whistles. At their end there are fungi for organizing ventilation to the roof. The principle of operation is still as simple as with the products. The air entering the roof space looks for an exit and through the cornice gaps under pressure and temperature difference is taken out of the attic, thereby drying the room from moisture.

Aerators are divided into:

• continuous
• Point (pitch, ridge)

By the way, if you have a large attic space, then ventilation on the roof of a private house to a greater extent will occur due to point aerators. They are created in the form of a mushroom with a fan to provide additional thrust.

For a task such as roof ventilation from soft roof continuous aerators are right for you. This is due to the fact that soft material coatings imply a slight slope of the slope, and they are installed along the entire ridge. Such plates with holes for the hood will allow you to ventilate the entire volume of the room. One of their advantages is invisibility from the outside, thus you will keep the aesthetics of the building.

The type of aerator depends on:

• roof type
• roofing material
• Appointments of the attic space

So when choosing this type of ventilation, I advise you to think carefully and decide what is more important for you, a heavily ventilated attic or warm room to store some materials. For example, well-organized mansard roof ventilation will allow you to create attic space comfortable dwelling.

I hope I have convinced you that ventilation is necessary work, for which you need to think carefully about everything and create it so that it protects your wooden and insulating roof elements, and does not destroy them.

Modern roof structures are complex system in which the elements work effectively only by closely interacting and complementing each other. When creating a roof project from soft tiles, you need to take into account a lot: protect the insulation from getting wet, prevent rotting of the truss frame and premature wear of the coating. "Warm" roofs, devoid of an insulating air layer, deserve special attention. In order for the microclimate in such houses to be suitable for life, it is necessary to establish air circulation between the under-roof space and the atmosphere. To do this, a ventilated ridge is installed on pitched roofs, the installation of which is a prerequisite for the organization of forced.

Ventilated ridge - a device installed on pitched roofs to organize forced ventilation of the roof. It is a simple plastic device installed along the ridge of a roof made of soft tiles, corrugated board or metal tiles. ventilated ridge profile has the following functions:

1. Reliably seals the ridge connection of pitched roofs so that no leakage occurs through it. The triangular shape of the ridge makes it difficult to seal this weak spot roofs made of corrugated board and corrugated board, through which melt and rain water can seep.
2. Opens air access. The ventilation gap that is formed when installing a ridge of this design opens the way for the heated air inside the room to the street, which creates a kind of draft and forces the air to circulate inside the house.
3. Closes the ventilation gap from the penetration of insects and snow. The device of the ridge is conceived in such a way that water, snow or insects cannot flow into it.
4. Lets evaporate excess moisture. Vapors saturated with moisture are a product of human activity. Together with the air, they rise up, cool and condense on the elements of the truss frame. The heat-insulating layer of a roof made of corrugated board, soft tiles or metal tiles, due to wetting, loses most of its heat-saving properties, and the wood of the frame rots and becomes moldy. Mounting a ventilated ridge solves this problem by opening the air to oxygen and allowing excess vaga to evaporate.

Note! Installation of a ridge with ventilation holes is part of the arrangement of a forced ventilation system for a roof made of soft tiles, corrugated board or metal tiles. In order for ventilation to work, air vents are installed in the cornices, fence places fresh air from the atmosphere.

Installation of a ventilated ridge does not spoil appearance roofs, at quality installation this element of the ventilation system cannot be seen. To make the installation site look more aesthetic, a strip of soft tiles or metallic profile, which protects the aerator from exposure to sunlight and the penetration of atmospheric moisture.

Operating principle

In the old days, builders did not even think about installing a ventilated ridge, since air naturally circulated through cracks or gaps in building materials and structures. or corrugated board requires almost complete tightness, installation is carried out in the form of a kind of "pie", in which there is a layer of insulation, waterproofing and vapor barrier. This design does not leave a single slit to the air, which is why a stuffy, humid microclimate is established inside the house. To solve this problem, it is necessary at the project approval stage to develop high-quality ventilation. Depending on the type of roof, there are 2 options for ventilation systems:

• Natural. Natural type ventilation is equipped for houses with "cold" roofs, in which the attic is not heated. With this design, dormer windows are made in the roof slope, which are necessary for air circulation. In this case, an unheated attic acts as an "air cushion" that isolates heated rooms from cold roof. Mounting a ridge with ventilation holes is extremely rare under such circumstances.
• Forced. Forced ventilation works on the principle of convection, which means that heated air always rises. Roofs with a heated attic made of metal tiles, corrugated board and roll materials equipped with a ridge aerator, as well as eaves, to force air masses to circulate between the room and the atmosphere. The air flow enters roof structure through the air, heats up and rises to the ceiling, exiting through a ventilated ridge and making room for fresh air.

Important! Forced ventilation was developed on the basis of physical properties gas. For its operation, no power sources are needed, since thrust is created according to the law of convection: warm air rises, and cold air sinks down. To achieve maximum efficiency ventilation system, its elements are placed evenly over the entire roof area from corrugated board, metal tiles or rolled materials.

Types of aerators

The design of the ventilation system depends on the area of ​​​​the slopes, the nature of the use of the under-roof space and the roofing material used. Installation of ventilation for "warm" mansard roofs is more complicated and more expensive than for cold ones. To determine optimal composition and mutual arrangement elements, perform installation based on determining the volume of air in the attic. The following types of aerators are used for ventilated ridge equipment:

Note! The simplest and inexpensive way ventilated ridge equipment - the use of corrugated ventilation tape. It is sold in rolls, and on the underside of the tape is a self-adhesive layer with a protective film. To install, you need to remove protective film, glue the tape on both sides of the ridge, and then install the metal ridge bar.

Functions

To the unprofessional, ridge ventilation may seem like an unnecessary overhead and an additional cost, but experienced roofers know that this simple measure increases the life of the truss frame and roof covering. A well-designed and installed ventilation system performs the following tasks:

1. Optimizes the microclimate in living quarters. Thanks to the constant flow of air saturated with oxygen, the house is always fresh, not stuffy, and a comfortable temperature regime is maintained.
2. Extends the life of the roofing. The ventilated ridge profile prevents bitumen-based roll materials from swelling due to solar radiation, allows excess moisture to evaporate, which favorably affects the service life of roofs made of metal tiles and corrugated board.
3. Maintains a healthy state of the rafter frame and battens. Thanks to the aerator, excess moisture evaporates, and the wood of the roof frame does not suffer from rot, mold and fungus.
4. Does not allow the insulation to get wet. Due to the constant air circulation, the insulation is ventilated and remains dry, which maintains the thermal insulation qualities of the material at a high level.
5. Makes the use of bitumen-based materials safer. Air circulation through aerators eliminates the possibility of penetration of bituminous vapors, which are considered harmful to human health, inside the premises.

Note! Dormer windows, installed during the organization of natural ventilation, are located at half the height of the slope, which is why stagnant zones are formed under the very ridge, where the air does not circulate at all. When installing forced ventilation, this problem does not arise, since the aerators are installed directly on the ridge connection, which is the highest point of the roof.

Video instruction

The safety and reliability of many modern houses largely depends on the right organized ventilation subroofing space of a soft roof.

Soft roof: do you need ventilation

• It is obvious that in any residential area there are water vapor. According to the laws of physics, these vapors, together with warm air, rise up and concentrate under the roofing. As a result, it begins to heat up from the inside. The snow that falls on the roof melts and ice crusts form near it. If a upper layer As the surface heats up, the ice will continue to melt. Then it is likely that:

• the roof at the joints of the coating will begin to leak;
• melt water, flowing down the slope, will begin to freeze when it reaches cold areas (cornice overhangs and gutters). This is how icicles and snow-ice masses are formed.

If you see a large number of icicles “decorating” gutters and cornices, this is the first signal that ridge ventilation for a soft roof is either missing or not done correctly.

• When the outside temperature fluctuates drastically (usually in spring and autumn) inside roofs condense moisture. It is formed by the contact of warm steam coming from interior spaces, and colder surfaces. Moisture finds ways to penetrate any roof structure and materials. First of all, this concerns:

• insulation;
• crates;
• rafters;
• overlap.

The result will be mold and fungi that will begin to destroy the structure of the materials used. For example, a heater moistened by only 5% is no longer able to perform its functions.

• The lack of ventilation of the roof made of flexible tiles becomes a source of inconvenience even on hot days. The coating becomes very hot, and the temperature in the under-roof space rises. At the same time, staying in the attic becomes quite uncomfortable.
• Dormer windows are traditionally installed in attics, however, they are usually ineffective. In the attic, there will certainly be places where air stagnates due to insufficient circulation. Imagine how much worse the situation is when the ventilation openings on the gables are tightly closed.

Main Functions

Soft roof ventilation works on the principle of air mass convection. In other words, the air tends to rise from the lower sections of the roof, cornices or overhangs, in the direction of the ridge, using special channels for this, passing through the roofing pie, or the entire area of ​​​​the attic space.

It is designed to solve certain problems:

• removes condensate formed from moisture vapor;
• levels the temperature difference on the surface of the flexible coating, which eliminates the melting of snow from below;
• prevents overheating of the soft cover from the sun's rays.

Since the traditional scheme is not effective enough, more efficient methods are required.

Device

Let's note the main elements of the roof hood:

• passing elements. The passage of ventilation through a soft roof, generally speaking, is an opening through the ceiling through the roof. Inside it passes a pipe made of metal, the wall thickness of which is more than a millimeter;
• exhaust holes;
• products on cornice overhangs;
• an air gap of 5 mm, which is left between the crate and the thermal insulation layer. To do this, a counter-lattice is stuffed on the rafters.

The air outlet is carried out in two versions: point or continuous.

• Dot set on separate sections stingray or skate. They are mushroom-shaped. Aerators of this type are either integrated into the general ventilation system of the building, or equipped with a built-in hood.
• Continuous systems, installed along the entire ridge, can be installed on almost any roof, especially on bitumen.

Installation

Ridge ventilation today is undoubtedly one of the highest quality and most reliable. Used to organize continuous ventilation of a soft roof roof aerator is a rigid plastic construction top part which is solid and looks like a corner, and perforated walls. They usually consist of elements such as:

• protective barrier;
• structural ribs;
• partitions;
• connecting endings.

To mount this system, several grooves are made in the ridge beam. It is recommended to choose them by 15 mm, which should be no closer than 30 cm from the edges of the ridge. In the future, they are blocked ridge element. This design ensures the outflow of air from the under-roof space along the entire beam.

Mounting Features

• If the aerator is installed on a finished roof, the mounted ridge tiles must first be removed.
• They mark the installation site of the ridge, mark the places for cutting the air vents, stepping back from the ridge by 15 mm.
• Cut a hole along the chalk line using circular saw. The depth must be adjusted so as not to damage the overlap.

Be careful not to hit the nails with the saw.

• Tiled petals are nailed to entire sections, the partitions should remain open.
• On each side of the ridge aerator there are latches that connect the elements of the ridge aerator.
• It is installed in the place intended for it and screwed with self-tapping screws.
• It is also necessary to process the ends. Silicone sealant works best for this.

• The profile is covered from above with the main roofing material. The width of the material used should be, on the one hand, less than the width of the ridge, so as not to cover the ventilation holes, and on the other, not narrower than it, otherwise the aesthetic appearance of the structure may be impaired.

Why ventilation may be needed, not everyone knows, but if you ask a person who is far from construction why an attic is needed in the house, he will answer without hesitation that it is for warmth. Warmly, of course, means a good microclimate in a house or a city apartment. Of course, the city dweller will also note that attics contain some communications, for example, heating, but not every one of these rooms is used only for such technical purposes. By the way, it is on the example of city houses that you can see how many holes are in the attic. And these are not glazed windows, but through holes, so you can understand how strong drafts are walking under the roof of the house.

They are simply necessary there, because they carry away not so much heat from the house as excess moisture. And if there were no such ventilation in the attic, it would become useless. Then a reasonable question arises: how do they make attics in houses where people live, full-fledged heating works and windows can be closed hermetically in case of wind, cold and rain? Is it possible that a real "" is being created in these rooms? Not at all. More precisely, ideally, the attic should have the same microclimate as in the rest of the house, and only if the attic is insulated with gross errors, then the microclimate becomes much worse, and not only in the attic.

Even mansard roof must be ventilated, and this is achieved by various methods. Their essence boils down to one thing: the under-roof space must be blown. And for this, a special gap is made between the actual roofing material and the rough roof. As a rule, the latter is a “multi-layered cake”, which uses at least two membrane materials, as well as insulating mats. The device of this "pie" is well known to every modern professional roofer.

But back to the roof space. Sometimes the roof area is so significant, and the configuration is so complex that it is impossible to ventilate all this space only due to gaps alone. Therefore, they outline such places in which special fans have to be mounted. Often, changes are made to the design of the attic itself related to the arrangement of dormer windows or the so-called roof bay windows. Remote windows are often made, but their arrangement is not directly connected with roof ventilation, and may even complicate it, since the roof surface becomes much more indented.

What causes poor roof ventilation?

It is never worth ignoring the roof ventilation device, because otherwise undesirable processes will occur, leading to the destruction of building structures. Let's imagine that heat comes from the house under the roof. On the other, outer side of the roof, it is cold. Then condensation will accumulate under the roof. It can be removed by constant ventilation. Even in those houses where communications are not provided for, completely flat rooms were made above the last floor. Their function was to ventilate the roof almost constantly. AT high-rise building under such a roof it was no longer as warm as directly in heated apartments, so condensate did not accumulate there so much, and it was easier to get rid of it by ventilation.

How can poor ventilation affect a soft roof? Also very negative. As a rule, these materials lie on a continuous crate or on concrete base. But excessive moisture coming from the inside can cause the roofing material to delaminate and exfoliate from the base. This will further lead to its depressurization, as a result of which the roof will begin to leak.

A roof covered with iron can rust over time, which will also weaken protective properties roofs, as in the first case. In addition, the shedding of hard roofing material from the roof is also a danger to all those who are below near the house.

And if in urban buildings hardly anyone decides to build a roof with a violation of its ventilation, then with private buildings everything is somewhat different, and there roofing masters often have to eliminate the mistakes made by non-professional builders.

How to ventilate the roof in a private house

There are several ways of under-roofing space in private buildings. This is:

• dormer windows in the attic, which are widely used for non-mansard roofs;
• ventilation of the gable roof ridge, which will also help for the attic;
• eaves type of ventilation;
• installation of roof fans;
• the use of piece elements with ventilation holes;
• arrangement of skates of a special design;
• ventilation gaps provided initially during installation or during the reconstruction of the roof.

It is clear that not every roofing material can implement a specific ventilation method. After all, roofs are made of different materials and their division only into hard and soft can be considered very approximate. For example, clay tiles and metal tiles, for all their external similarity - various materials, and if the first is an exclusively piece material, moreover, it is very fragile for certain types of impact, then the second can be attributed to the sheet type. In this regard, the metal tile is even closer to corrugated board. And if this material is not brittle, then it is subject to corrosion in those places where its protective coating has been broken.

By itself, a metal tile is such a material that is stuffed onto a crate, moreover, not always continuous. Installing a counter-lattice under it is an ideal way out if needed. warm attic. The counter-lattice not only raises the crate to a certain height in order to withstand the height of the ventilation gap, but also in order to fix the membrane on the rafter system. This membrane is a vapor barrier film with a special kind of holes that prevent moisture from entering the rafter system and, at the same time, release vapors from the attic room. Until these vapors become fog (from the point of view of physics, fog is a suspension of water droplets in the air, which we see as steam) and condensate, they are picked up by air and carried out from under the roof.

With this design of the roof, gaps appear at the cornices. Also, ridge vents are made on the same roofs to ensure constant traction, due to which effective ventilation occurs.

It is often possible to reclassify an attic into an attic if the room there is made all-weather. In this case, do not forget about the roof. But if it is so well laid that you don’t want to disassemble it, but at the same time it is not properly ventilated? There is a way out of the situation. As a rule, there is at least some gap in the crate, and our task is to make it ventilate. To make ventilation effective, you can put special pipes on the roof through which steam will be removed from the under-roof space. For this, it is better to use plastic pipes, as they are not afraid of weather influences. They need to be installed closer to the roof ridge, cutting holes in the metal tile for them. The number of pipes is calculated according to the area of ​​\u200b\u200bthe roof - for 50–60 m 2, one at a time.

If the house is located in snowy areas, then you need to calculate the height of the pipes according to the maximum snow cap, and cover each pipe with a fungus so that precipitation does not get there.

Each pipe, when installed on the roof, must have a seal, because otherwise the metal tile may corrode at the cut site. The sealing element is made of silicone. You can also use specialized outlet elements for roofs under the pipe. They provide a hermetic connection of the pipe to the roof and facilitate the installation of the pipe in vertical position. These items contain a sealing circle that needs to be silicone grease to better perform their functions.

You should also pay attention to the tools with which the metal tile will be cut. If you take scissors for metal, they will not ruffle the coating of the sheet, but, on the contrary, will press it at the cut point to the base, as they work in compression. Using a hacksaw is a little worse. But even more damage can be done with an electric circular saw.

Working with such tools and devices will allow not to rebuild the roof, but to make it ventilated. If it still seems to you that a lot of moisture is collecting in the attic, then you can increase the number of pipes on the roof in the next summer season.

No less often than a metal tile, it is used in the construction of the roof of private houses. shingles. It is easy to mount, it makes little noise, and besides, it has a beautiful appearance, which can compete with a metal tile. But the softness of the material leads to the fact that quite often under flexible tiles put continuous crate, trying to provide additional strength . But at the same time they lose in the ability to ventilate the under-roof space. Therefore, when arranging such a roof, the crate must be done with gaps, even if they are small. After all, often during the construction of the attic, instead of the usual uninsulated attic, the roofing material is changed to a lighter one so as not to create additional loads on the walls and foundation (do not forget about the “pie” of insulation, which is very heavy). Therefore, rigid tiles can be removed from the roof and replaced with flexible tiles.

When arranging the truss system, it is necessary to maintain a distance from the roof to the insulation equal to at least 5 cm. At the top of the roof, aerators or ridge vents must be provided. Air intake into the ventilated space will be carried out from the lower edges of the slopes, and here a problem may arise: no matter how hard you try to keep this “air intake” free, birds can occupy it, blinding or building their nests there. You can protect yourself from this by installing a grid.

Since the rafter system is made in insulated attics with a double crate, it is possible to make two ventilation circuits in it at once. One will pass directly under the roof, between it and the crate. The second "channel" will be located between the insulation, covered with a membrane, and the upper membrane, laid on top of the counter-lattice. At the same time, the type of the lowest membrane covering the insulation is a wind protection, and the type of the upper membrane is a vapor barrier. Approximately the same membrane is located under the heat insulator inside the attic room.

Above, we have repeatedly touched on the topic of a ventilated skate, but did not go into the details of this design. The horse can do it in several ways. Note that due to top position air enters it due to natural draft or due to convection. Since we need to remove warm air, saturated with steam, then, according to the laws of physics, it will rise exactly to the ridge if it is in the gap between the roof and truss system covered with wind protection.

In particular, air can enter the space under the roof from the side of the eaves. But through what it will be displayed depends on the design ridge ventilation. It can be implemented:

• on pipes;
• in the form of a continuous aerator;
• with the help of deflectors;
• with tiles for ventilation.

The use of tiles for ventilation is advisable on those roofs that have a large slope angle. This is a guarantee that the grate in such a tile will not clog. Deflectors are also effective where snow does not accumulate on the roof. The principle of their work is that they contribute to the creation of vacuum and additional traction under the roof.

But for snowy regions and at small angles of roof slopes, other methods have been invented, in particular - solid ridge. It makes the design of the roof interesting, and it all depends on the imagination of the architect: such a house acquires either something ancient Japanese in its style, or is associated with old Russian towers. The idea is that over the ridge, as it were, another roof is made with very short slopes, literally one or two rows of tiles. This roof is called an aerator. It is raised above the main slopes, and air escapes from under it through the resulting gap. The upper slopes are needed so that precipitation does not linger on the aerator. The same membrane serves as protection from birds, dust and slanting rain. Sometimes so-called fleecy membranes are used, on which the pile collects the smallest droplets, preventing them from turning into a continuous layer of moisture.

If even such a gap can become clogged with snow, then special deflectors with pipes are used. Even if there is a snow cap on the roof, the ventilation under the roof will still not stop. Pipes will work great and forced ventilation roofs. To do this, a low-noise fan can be built into each of them. A decision on forced ventilation can be made when a complete exchange of air under the roof is not ensured for half an hour. Fans will save you the hassle of installing additional pipes.

There are also deflectors of this design, which ventilate the attic room itself, removing steam from it immediately above the roof. These devices very well save the room itself, and especially in winter, when you will not often ventilate it. The attic undergoes the greatest load from warm air, because it is the highest room in the house. And if we protect its insulation with a vapor barrier membrane, which is “”, then we doom the attic itself to saturation with water condensate, which is not able to overcome this membrane.

The deflector with access from the attic to the roof has a small cross section, compared, say, with open window or even a window, so it can only be compared with a hood. Such a device will not allow vapors to remain in the attic and at the same time - to penetrate into the insulation and under the roof.

It should also be clarified what a multilayer "pie" of the attic is. So, it consists of several layers, which from the side of the roof will go like this:

• roofing material;
• crate;
• counterlattice;
• wind protection;
• rafter system and insulation (can be laid between the rafters);
• vapor barrier;
• rough finish (drywall or plywood);
• clean finish.

How to ventilate a shed roof

If the roof of the house is made with one slope, then it is very simple. One has only to make the correct gap between the roof and the truss system, as the thrust in the gap will arise by itself due to the height difference. If the gap is small for complete air exchange, then additional ventilation pipes, as it was done on a gable roof.

How to ventilate a hip and hip roof

With this architecture, the roofs do not have gables. But this is not an obstacle to the organization of ventilation. It is built on the same principle as gable roofs, but at the same time, one should not forget that it is necessary to make inlet gaps for air around the entire perimeter of the roof. No matter how many slopes there are on a hipped roof, each of them must be ventilated.

A big “temptation” to forget about the ventilation of the under-roof space is given by a half-hipped roof, because its inclined end elements are relatively small in size. Ventilation here can be built in the same way as on the main roof slopes.

It is somewhat more difficult to think over the ventilation of the end slopes of the Dutch roof, since a window is located directly above them. This is an obstacle to the use of pipes, but grates or an aerator can be placed there.

In all these cases, if a wooden filing of the roof is performed, it should not be continuous, since air must enter the under-roof space through its gaps.

But, in addition to the above installation rules, it is also important to do exact calculation so that normal draft is created under the roof. Otherwise, all this will not work.

The longevity of the house depends on the correct laying of the roof and comfortable conditions living in it. But its quality depends not only on the selected materials for coating, heat and vapor barrier. Important role soft roof ventilation plays, which is often given little attention. It may not be completely clear to the average consumer why it is necessary to buy ventilation elements and are they needed at all? How can moisture appear under roofing materials in a newly built house if cracks have not yet formed in the coating? Let's try to understand the issues of the device and the indispensability of the ventilation system for a soft roof in a private housing construction.

Why do you need roof ventilation?

In the old days, the owners land plots built houses with pitched roofs, under which were located unheated attics. Ventilation for the roof was carried out through dormer windows installed on opposite gables.

Modern private buildings intended for permanent or temporary residence are built with heated attics and insulated roofs, which they had no idea about some five or six decades ago. In connection with changes in construction technology, there was a need for ventilation for a soft roof, which could once be dispensed with.

There are several reasons why you should consider ventilation. .

First of all

Warm during the cold season wet air, present inside the house, rises up to the roofing, where it accumulates and begins to heat it from the inside. result this process is the thawing of snow falling on the roof and the formation of an ice crust in the immediate vicinity of the soft roof.

With further heating of the upper layer of the coating, the ice continues to melt. In this case:

• leaks appear at the joints of roofing materials;
• melt water flows down the slope and freezes on cold eaves, as well as in gutters, forming a snow-ice mass or icicles.

So, the first signal of the absence or incorrect ventilation device intended for the roof is the presence a large number icicles on gutters and roof cornices.

Secondly

With sudden changes in outdoor temperature, which happens quite often in spring and autumn period, on the inner surface roof coverings, condensate is formed at the moment of contact of warm steam coming from the room with more cold roof. In this case, the greater the temperature difference, the more abundant the condensate.

The moisture formed in the process penetrates into any available structures and materials:

• insulation;
• crate;
• rafters;
• overlap.

As a result, mold appears, fungi develop, and the structure of materials is destroyed. And a heater moistened by only five percent loses its insulating qualities by half, which completely deprives it of the ability to perform its functions.

Thirdly

AT summer time under the action of sunlight, the soft roof heats up significantly, which can add extra degrees to the attic room in the absence of ventilation for the roof. In this case, staying in a room under the roof will become uncomfortable.

Fourth

Traditional dormer windows, despite their prevalence, are not effective enough. In any case, there are poorly ventilated areas in the attic in which air masses stagnate. But more unpleasant are the situations when illiterate owners close the ventilation openings on the gables tightly, not understanding what they are intended for.

The main functions of soft roof ventilation

Ventilation systems work on the principle of natural movement of warm masses from the bottom up. It is based on the convective method and implies the tendency of air to rise from the eaves or overhang towards the ridge through special channels inside the roofing pie or over the entire area of ​​the under-roof space.

Cold air is drawn in under the soft roof in the overhang area, and exits through aerators or a ridge.

Before roof ventilation a number of tasks are set:

• removal of condensate formed from wet vapors;
• ensuring the temperature balance on the surface of the soft roof to avoid melting snow from below;
• prevention of heating of the lower layers of the roof from overheated under sunbeams soft roofing.

Roof ventilation systems

The device of a ventilated soft roof is impossible without the design of the places of entry and exit of air. The entrances are located on the roof overhangs and are closed from the possible penetration of birds and small animals under the roof:

• perforated spotlights - plastic or metal;
• slats;
• wooden lining.

Roof ventilation elements are continuous or point.

aerator skate

It is a continuous outlet located at the top of the slope. It is mounted at the highest point along the entire length of the roof, which ensures uniform ventilation of the under-roof space. Ventilation ridges-aerators are covered with the main roofing material (in our case - soft), so they merge with the roof surface almost together.

Modern ridge aerators are made from durable plastic, which has high resistance to ultraviolet radiation and temperature extremes.

Aerator elements are equipped with built-in filters that protect against atmospheric precipitation, insects, foliage or needles from entering the ventilation space, which prevents difficult cleaning and getting wet heat-insulating layers. Ventilation skates are attached to special ribbed profiles made of plastic or metal.

Roof aerator

Point outlets, which are roof fans, are mounted on certain sections of the roof, not far from the ridge. Small aerators are installed one for every 60m2 of roofing, large ones - for 100m2. The distance between them is recommended to be kept within 10-12 meters.

Vertical aerators are installed on a base intended for roofing, pre-cut in the "pie" air vent up to the vapor barrier. They are fixed to the slabs with self-tapping screws, and after installation, they are carefully glued around with soft roofing materials.

The joints between the aerator and the roof should be carefully insulated to prevent moisture from getting under the roof.

Ventilation features

Many owners of private houses faced problems associated with the lack of ventilation of soft roofs. Most of them realized that the quality and durability of the coating can only be ensured if you take care of the air gap between the thermal insulation and the crate on which the roofing material is laid. As a rule, they make it four centimeters thick.