Ventilated roof. Roof ventilation: recommendations for calculation and installation. Ventilation roofing tape

Everyone who is somehow involved in construction should at least remotely know the device of a ventilated roof.

Recall that there are 3 main ventilation circuits:

There must be a ventilated space in which there will be little room for fresh air to flow. It is they who will take the formed moisture in the summer and bring it out. In order for such a design of a ventilated roof to work efficiently and without interruptions, it is very important to competently approach the issue of laying the roof on the crate.

If the rafter system is already installed, take care of the roofing material. It must match the type of room. For example, if an unheated room is planned, then its service life will be limited only by the shelf life of the selected materials, and ventilation will be natural.

But in order for the building to last even longer, use forced ventilation, where the ventilation outlet to the roof, or rather, the outlet space, will be occupied by a weather vane.

Let's remember what elements an uninsulated roof consists of:

Rafter;
crate;
Roofing material;
Waterproofing films.

The waterproofing film plays an important role, because, being attached to the rafters with the help of slats, even after the roof is worn out, it will provide some protection from moisture from the outside. Also, waterproofing has a long service life, so it can reliably protect the passage of ventilation through the roof.

Especially similar material is suitable for summer cottages. The film covered with slate in favorable conditions can withstand up to 50 years of constant use! But do not forget about the special arrangement of the "roofing pie" for all private houses.

In addition to insulation for ventilation, a diffusion waterproofing film is usually applied. Thanks to it, the under-roof structures will remain dry, and steam will be able to pass through the smallest pores of the material. Also, another advantage is the reliable protection from the wind during the use of this film.

But the use of a diffusion film is justified only during the installation of certain gaps. Best of all, the film will be able to prove itself by filling the gaps between the heat-insulating structure, the roof and the film. In almost all other cases, this film will not allow water vapor to pass through, which will cause the ventilation outlets to the roof to stop working properly. Instead, it would be better to use an anti-condensation film.

roof weather vane, which organizes forced ventilation. It is worth noting that you can make.

Recall that a ventilated roof consists of finishing materials and insulation. Water vapor usually reaches the last and stops in this layer, due to which the insulation quickly loses its original properties. In the future, excessive moisture will appear on the walls and ceiling, and this threatens with serious consequences.

In order to avoid bad consequences and mount ventilation. But we should not forget about roofing materials, because they also play an important role in warming the home. By showing balance, you will definitely be able to achieve the desired result in construction!

Condensation formed on the elements of the roof structure can cause premature failure. This problem is especially relevant during the heating season, with a significant difference between the temperature outside and inside the building. At the same time, the insulation experiences a serious load, the range of values \u200b\u200bcan reach tens of degrees, as a result of which drops of moisture settle on it, blocking the thermal insulation properties of the material.

The best way to solve the problem is to install the roof of the house with ventilation. In winter, it will ensure the effectiveness of thermal insulation, in summer it will reduce discomfort due to heat, preventing the flow of heated air. The cost of arranging the roof will increase slightly, but already in the first years of its operation, they are guaranteed to pay off.

Ventilated roof construction

The main goal in the design of a ventilated roof is the choice of building materials. You will need to take into account other important points: the number of gaps for air passage, the pitch of the crate, the type of waterproofing film and other nuances. So, when using materials with polymers, the ventilation space should be larger than when installing natural roofing.

The main task of a ventilated roof is to ensure air circulation and prevent condensation. The design contains three circuits that ensure the movement of air flows in the following spaces:

between waterproofing and roofing;
directly under the roofing;
between hydro and thermal insulation.

By design, there are two main types of ventilated roofs:

non-insulated, the main scope of application is economic and industrial buildings;
insulated - used at all facilities where people stay for a long time: housing, commercial and administrative buildings, other buildings.

The main elements of a ventilated roof:

rafter system;
crate;
waterproofing;
insulation (not on all objects);
roofing.

Advantages of a ventilated roof

An important feature of such roofs is the presence of vents and special gaps in the ridge through which air is circulated. One of the options for ventilating a roofing pie is to use a heat-insulating material with channels for air flow. It doesn't matter if you are installing a copper roof, with metal tiles or bitumen, you will need to designate the exit areas of the ventilation ducts.

The use of a ventilated roof allows you to significantly improve the thermal insulation properties of the roof with virtually no additional costs. There are many advantages to this design:

the formation of rot, fungi and other microorganisms is practically excluded;
the risk of swelling of the roofing cake is minimal;
increases the resistance of the coating to most external factors: precipitation, extremely low or high temperatures, decay, and others.

The use of a ventilated roof is one way to extend the life of the roof covering, avoid condensation and increase the energy efficiency of the structure. When developing a project, you will need to take into account many nuances, so you will have to responsibly choose a company that can be entrusted with such work.

Which differ not only in the complexity of the device, but also in characteristics, installation methods. Among such diverse types in a separate group is a ventilated roof, which is distinguished by excellent protection against swelling of the roofing carpet, wetting the cake, the appearance of mold, fungus.

Today, such a roof is considered one of the most optimal, its construction is economical, possibly directly on top of the old structure. At the same time, it allows you to completely dry the wet insulation, truss systems. In our article, we will consider the device of such a roof and its features that made them so popular in private construction and in the construction of apartment buildings, industrial, outbuildings. In addition, we will find out what options for such a roof exist, how exactly they differ from each other. Our experts will share the secrets of installation, which can be done by hand, without calling a team of professional builders.

Ventilated roof construction

Ventilated roofs, whose designs are quite simple, include such basic components necessary for ventilation, such as:

ventilation of the space that is between the layers of waterproofing and insulation;
ventilation between the waterproofing and the roofing itself, it covers all planes, even if the design is complex;
direct ventilation under the roof itself, which is an element of the general ventilation system of the house.

It is the peculiarities of the location of the ventilation that distinguish such a roof from others, constant air inflows allow not only to effectively remove moisture to the outside, but also to control the temperature level. In this case, ventilation will greatly depend on whether the roof lathing system is properly arranged.

Scheme of ventilation of the roof of a non-residential attic.

The process of installing a ventilated roof has its own specifics. So, for ordinary outbuildings and garages, an uninsulated type of coating is excellent, which consists of the following elements:

rafter system;
crate;
waterproofing;
roofing material.

The film for waterproofing is attached to the rafters with slats, it does not allow moisture to get inside, extends the life of the roof. But such a design is cold, that is, a layer of heat insulator is completely absent in it. This is not suitable for private residential buildings; here it is necessary to arrange another roofing pie. In addition to the above layers, in this case, a slab insulation is required, an anti-condensate film that prevents condensation from forming on the roof elements. Such material consists of several layers:

two layers of laminated film;
moisture-absorbing non-woven material;
polypropylene fabric.

In addition, the device of a ventilated roof assumes the presence of vents in the lower part of the cornice, ventilated skates.

Advantages of a ventilated roof

A ventilated roof differs from other structures in the following advantages that put it in the first place:

Installation of such a roof is possible even at sub-zero temperatures, the only exception is the presence of heavy rain, heavy snowfall, frost, which drops below minus twenty degrees Celsius.
During the reconstruction, the removal of the old roofing is minimal, including preparatory work; this makes it possible to save money and time for installation, the cost of the roof is much less.
During further operation, everything is completely dried, including floor slabs, heat insulators, old roofing (if any). This allows you to completely remove the risk of rot, mold, fungus, which are very dangerous for the overall roof structure.
The old roof covering, which is located under the new ventilated structure, after drying, completely restores all its functions, that is, a kind of double roof is obtained.
The swelling of the roofing carpet is completely eliminated.
The resistance of the new coating increases, this roof is very resistant to frost, ultraviolet radiation, rotting, strong temperature changes, movements of ice and snow masses in winter, thermal expansion, and various mechanical damage.

How to properly design ventilation?

The design of such a structure always involves the thoroughness of the preparatory work. During the execution of the project, it is necessary to provide that:

water from the surface always flowed down, that is, proper protection against its influence must be created;
steam rushed up from the premises, that is, the presence of vapor protection is also required.

The device of such a roof is that rare case when the walls of the house should not breathe! Otherwise, the moisture that can linger in them will lead to delamination of the building material.

Ventilated roof options

Today, a variety of types of ventilated roofs are used, among which pitched and flat ones stand out. They can be used for a wide variety of buildings, the materials for them, however, are the same, only the design differs. Consider these two main design options, their differences, device diagrams, advantages.

flat roofs

Similar ones began to be used from the beginning of the eighties, when it became possible to use heat-insulating materials with ventilation ducts that help remove excess moisture. Most often, such roofs were made for apartment buildings, where they were most effective.

The pie consisted of the following elements:

concrete slab as a base for the roof;
vapor barrier;
a layer of mineral wool slab insulation, in the thickness of which was the end of the ventilation pipe, the so-called aerator, which removes excess moisture;
cement-sand screed;
bituminous waterproofing layer;
polyurethane material;
a layer of polyurethane mastic;
roofing material.

A concrete parapet was erected on the sides, which was protected from the roofing pie with a layer of sprayed or bulk material. Today, this function is performed by polyurethane foam, which provides excellent insulation and sealing. All outlets of ventilation pipes and aerators are also insulated with this material. All flat roofs are considered cold, but still they continue to be popular due to their convenience and savings in building materials during installation.

pitched roofs

They differ from flat ones in that air flows enter through the lower overhangs, and exit through the ridge, while all excess moisture that accumulates under the roof space in the insulation is removed with them. Ventilation in this case can be forced, for which roof fans are installed, the coating is recommended to be light, preferably having a wavy texture. The roof can be insulated and non-insulated, the roofing cake differs only in the presence or absence of a heat insulator layer. For residential buildings, it is necessary to have a heater, in this case, mineral wools in the form of plates are excellent, which are very easy to install, provide an insulated coating, and the absence of cold bridges.

Mounting

The ventilated roof is mounted in the following order:

Preparation of the base for work, including the elimination of cracks and potholes. This may be the usual laying of cement mortar, leveling the entire surface, or asphalting the slab. It must be remembered that the minimum slope of such a roof should be from two to three degrees!
Next comes the insulation, in which strips and cracks are unacceptable. Most often, mineral wool or glass wool is used for this, which guarantee excellent quality and low installation costs.
Depending on the type of roof, further installation work may vary, but basically a waterproofing layer, a cement screed, is laid.
As a roof covering, rolled welded materials are used, which provide excellent quality. Laying is carried out using a gas burner, while the bitumen is melted, the material itself is firmly glued to the base. Lateral overlap should be from one millimeter to five.

When installing, do not forget to mark the outlets of the ventilation ducts, isolate them properly to ensure the normal functioning of the roof. Only in this case will it acquire its proper qualities.

Today, a wide variety of roof structures are becoming widespread, which differ not only in the complexity of the device, but also in the roofing pie, characteristics, and installation methods. Among such a variety of types in a separate group is a ventilated roof, which is distinguished by excellent protection against swelling of the roofing carpet, wetting the cake, the appearance of mold, fungus.

Today, such a roof is considered one of the most optimal, its construction is economical, possibly directly on top of the old structure. At the same time, the ventilated roof allows you to completely dry the wet insulation, truss systems. In our article, we will consider the device of such a roof and its features that made them so popular in private construction and in the construction of apartment buildings, industrial, outbuildings. In addition, we will find out what options for such a roof exist, how exactly they differ from each other. Our experts will share the secrets of installation, which can be done by hand, without calling a team of professional builders.

Ventilated roof construction

Ventilated roofs, whose designs are quite simple, include such basic components necessary for ventilation, such as:

ventilation of the space that is between the layers of waterproofing and insulation;
ventilation between the waterproofing and the roofing itself, it covers all planes, even if the design is complex;
direct ventilation under the roof itself, which is an element of the general ventilation system of the house.

Scheme of ventilation of the roof of a non-residential attic.

The process of installing a ventilated roof has its own specifics. So, for ordinary outbuildings and garages, an uninsulated type of coating is excellent, which consists of the following elements:

rafter system;
crate;
waterproofing;
roofing material.

two layers of laminated film;
moisture-absorbing non-woven material;
polypropylene fabric.

In addition, the device of a ventilated roof assumes the presence of vents in the lower part of the cornice, ventilated skates.

Advantages of a ventilated roof

A ventilated roof differs from other structures in the following advantages that put it in the first place:

Installation of such a roof is possible even at sub-zero temperatures, the only exception is the presence of heavy rain, heavy snowfall, frost, which drops below minus twenty degrees Celsius.
During the reconstruction, the removal of the old roofing is minimal, including preparatory work; this makes it possible to save money and time for installation, the cost of the roof is much less.
During further operation, all elements of the roof are completely dried, including floor slabs, heat insulators, old roofing (if any). This allows you to completely remove the risk of rot, mold, fungus, which are very dangerous for the overall roof structure.
The old roof covering, which is located under the new ventilated structure, after drying, completely restores all its functions, that is, a kind of double roof is obtained.
The swelling of the roofing carpet is completely eliminated.
The resistance of the new coating increases, this roof is very resistant to frost, ultraviolet radiation, rotting, strong temperature changes, movements of ice and snow masses in winter, thermal expansion, and various mechanical damage.

How to properly design ventilation?

The design of such a structure always involves the thoroughness of the preparatory work. During the execution of the project, it is necessary to provide that:

water from the surface always flowed down, that is, proper protection against its influence must be created;
steam rushed up from the premises, that is, the presence of vapor protection is also required.

The device of such a roof is that rare case when the walls of the house should not breathe! Otherwise, the moisture that can linger in them will lead to delamination of the building material.

Ventilated roof options

flat roofs

Such flat roofs have been used since the early eighties, when it became possible to use heat-insulating materials with ventilation ducts to help remove excess moisture. Most often, such roofs were made for apartment buildings, where they were most effective.

The pie consisted of the following elements:

concrete slab as a base for the roof;
vapor barrier;
a layer of mineral wool slab insulation, in the thickness of which was the end of the ventilation pipe, the so-called aerator, which removes excess moisture;
cement-sand screed;
bituminous waterproofing layer;
polyurethane material;
a layer of polyurethane mastic;
roofing material.

pitched roofs

Pitched roofs differ from flat ones in that air flows enter through the lower overhangs and exit through the ridge, while all excess moisture that accumulates under the roof space in the insulation is removed with them. Ventilation in this case can be forced, for which roof fans are installed, the coating is recommended to be light, preferably having a wavy texture. The roof can be insulated and non-insulated, the roofing cake differs only in the presence or absence of a heat insulator layer. For residential buildings, it is necessary to have a heater, in this case, mineral wools in the form of plates are excellent, which are very easy to install, provide an insulated coating, and the absence of cold bridges.

Mounting

The ventilated roof is mounted in the following order:

Preparation of the base for work, including the elimination of cracks and potholes. This may be the usual laying of cement mortar, leveling the entire surface, or asphalting the slab. It must be remembered that the minimum slope of such a roof should be from two to three degrees!
Next comes the laying of a layer of vapor barrier film and insulation, in which strips and cracks are unacceptable. Most often, mineral wool or glass wool is used for this, which guarantee excellent quality and low installation costs.
Depending on the type of roof, further installation work may vary, but basically a waterproofing layer, a cement screed, is laid.
As a roof covering, rolled welded materials are used, which provide excellent quality. Laying is carried out using a gas burner, while the bitumen is melted, the material itself is firmly glued to the base. Lateral overlap should be from one millimeter to five.

When building a house, it is imperative to consider high-quality roof ventilation. This is one of the main tasks of designing and building a durable home. Without a good ventilation system, the entire roof structure will deteriorate very quickly. First of all, all wooden elements will suffer from moisture, which will already reduce the degree of safety and comfort of the building. Then the roofing material will begin to collapse. We will examine in more detail the issues of bringing ventilation to the roof of the house and the natural ventilation of the roof.

Source megapolis-sc.ru

Where does moisture come from in the roofing "pie"

The roof of a residential building is a complex system consisting of a wooden frame, roofing, as well as layers of waterproofing, vapor barrier, and thermal insulation. In general, a well-built roof is a sealed package. But moisture still gets on the wooden elements and insulation. The fact is that air containing water vapor penetrates into the roofing pie. With a temperature difference, steam in the form of condensate settles on the surfaces of the inner layers.

Even through the most reliable vapor barrier made of steam and waterproofing, a little air still penetrates into the “pie”. In addition, air can enter through "breathable" wall materials such as porous blocks, wood or cellular concrete. Therefore, condensation cannot be avoided. This phenomenon is especially pronounced during precipitation or during fogs, when the concentration of moisture in the air rises noticeably.

Source pinterest.com

Purpose of roof ventilation

The ventilation system of the roofing system simultaneously performs several important functions, which increase the comfort of living in the house and extend the operational life of the roof.

The main function of ventilation is removal of vapors from the under-roof space that rise from living quarters. During ventilation, the circulating air prevents moisture from accumulating on the inner surface of the roofing pie, from where it can penetrate into the roof.

The movement of air masses in the roof ensures not only the weathering of excess moisture, but also uniform temperature distribution. As a result, all elements of the "pie" warm up quite well during the heating season. Therefore, a roof with good ventilation is less overgrown with icicles, which create an additional load on the coating.

In summer, ventilation is necessary for roof cooling. This is especially important for houses with soft roofing, which is very hot and can melt and slide even with a high slope of slopes.

Source gkds.ru

Natural and forced ventilation

For their long and trouble-free operation, both types of ventilation systems require careful calculations, which will show which one is better to use in terms of efficiency and economy. Specialists in the calculations must take into account the features of these systems.

natural ventilation

It is carried out due to the convective flow, which occurs due to the interaction of warm and cold air masses. For such ventilation to work, it is necessary to assemble a roofing cake with a gap (at least 5 cm) between the lower waterproofing layer and the roofing layer.

Effective natural ventilation of the roof is possible with proper design and competent work of builders. It is not easy to create conditions for her. It is necessary to carefully calculate the system of battens and counter battens, and ensure the continuity of the ventilated circuit. But most importantly - it is necessary to provide ventilation vents. There should be at least two of them in the ridge zone and the same number in the cornice zone.

The air in the under-roof space heats up, and naturally rises up, where it is forced out through the ridge vents. Fresh air enters through the cornice openings. Thanks to this process, condensate does not settle on the roof surface.

Source oventilyacii.ru

If the slope of the slopes is small, in winter the ridge vents can be clogged with snow. To prevent this, you need to install special pipes along the ridge that will rise above the snow level.

Forced ventilation

Since additional equipment is required for the organization of artificial ventilation, from a technical point of view this is a more complicated option. There are rare exceptions when designing forced ventilation is easier than calculating natural ventilation, but these are still exceptions that prove the rule.

It has become widespread as a result of the fact that, firstly, low and completely flat roofs have come into fashion, in which it is simply impossible to create natural ventilation. Secondly, new building technologies have appeared that allow automating and improving the maintenance of cottages.

Forced systems are installed not only in houses with a flat roof, but also in houses that, for one reason or another, cannot be provided with roof vents. Recently, more and more solid cottages with standard roofs are equipped with forced ventilation, as it is more reliable than natural.

Source nashicherdaki.ru

Forced ventilation can be carried out by installing a fan in the ridge outlet. To do this, you need to stretch a wire into the upper part of the roof. The second option is the installation of special devices that increase the intensity of air movement.

On our website you can get acquainted with the most popular from construction companies presented at the exhibition of houses "Low-Rise Country".

Ways to arrange ventilation

Roof ventilation can be achieved in a variety of ways. The choice of arrangement option depends on the architectural decision of the designer.

Aerators

Installing roof aerators is the most common option. The aerator is a part of a small piece of pipe with a flat base for installation on the surface and an umbrella that covers the upper opening of the pipe from precipitation. A protective filter is placed inside.

Source mtlarena.ru

Aerators can be installed according to various schemes. The location of these devices depends on the type of roof and the degree of humidity in the region. Usually aerators are located near the ridge. You can install them point by point. Experts believe that the most effective is the installation of a continuous gutter of aerators, stretched along the entire edge of the roof. It is advisable to install ventilation of this type simultaneously with the arrangement of the ventilation system of the entire building.

The advantage of aerators is that they do not interfere with the design of the house. In addition, when using them, the roofing should not be airtight, that is, it can be laid without the use of special tape and mounting foam.

On our website you can find contacts of construction companies that offer roof repair services. You can directly communicate with representatives by visiting the exhibition of houses "Low-Rise Country".

Ventilated cornice

The use of a ventilated eaves provides air access to the under-roof space. As a result, the roof is well ventilated, and the entire ventilation scheme of the building works better. The eaves for ventilation of the roof can be equipped in different ways:

usage spotlights for filing a roof;

installation ventilation grilles;

installation over cornice overhangs of special elements with products.

Source aihara-company.com

Insulating materials are not laid at the installation sites of the cornice ventilation channels. To protect them from precipitation, elements of the drainage system and snow retainers are used.

dormer window

Ventilation with a dormer window is also a fairly common option. Ventilation of the roof of the house in this way, among other things, improves the aesthetics of the facades. The shape of the windows can be different, and it is important at the design stage to think over such a type of windows that will correspond to the general style of the building.

Dormer windows are roof elements that are quite expensive to build. But they have their own undeniable advantages - high efficiency as a ventilation system and aesthetic appearance.

Source lestnitsygid.ru

Roof ventilation from metal tiles and corrugated board

These are the most common roofing materials in our country. They are very convenient in technology of application and price. They are made using the same technology and differ primarily in shape. The corrugated board looks less impressive, but at the same time it has stiffeners along the entire length.

In the process of arranging a metal-tiled or corrugated roof, difficulties arise with ventilation. The fact is that these materials are absolutely vapor-tight and thermally conductive. They heat up and cool down quickly, resulting in a lot of condensation on the inside. But even these materials make it possible to create high-quality roof ventilation - roof ventilation, which prolongs the life of the entire building.

Source ogolosha.ua

Manufacturers of metal tiles and corrugated board produce special additional elements with which ventilation passages are equipped. The main thing is to entrust the arrangement of the roof to specialists who will think over a good ventilation system. Since these materials do not retain heat very well, additional layers of hydro and thermal insulation are provided when they are used. In addition, these roofing materials themselves must be protected from moisture with special care. In connection with these features, roofs made of metal tiles and corrugated board are often equipped with forced ventilation.

Soft roof ventilation

Soft roofing under the influence of high temperatures can swell and melt. Therefore, it is so important for her to have ventilation, which will not only remove moisture from the roofing cake, but also cool the roof during the summer heat. Usually, the ventilation of the roof, the roof of which is made of bituminous tiles, is equipped with the help of aerators (valves).

Video description

Roof ventilation with valves (aerators)

Mansard roof ventilation

The ventilation system of the mansard roof performs an additional function - the regulation of the temperature regime in the premises of the upper level of the house. It is designed more carefully than roof ventilation over the attic. On the other hand, it is easier to protect the attic roofing pie from moisture, since attic rooms, unlike attic rooms, are heated and well ventilated.

In most cases, forced ventilation of the roof is not required to remove condensate from the attic roofing pie. But between the waterproofing and heat-insulating layer, a space is necessarily provided for the unhindered passage of air.

Video description

How to make ventilation in the attic roof

If the attic is rebuilt into an attic

A simple attic in order to expand the living space can be converted into an attic. In this case, the roof is usually rebuilt. Insulating and roofing materials are replaced with better ones. More efficient ventilation of the roofing pie is being arranged. However, if the roof is initially very well laid, you can improve it a little without disassembling it.

In any roof there is at least a very small gap in the crate. It needs to be turned into a ventilation duct. This is achieved by installing special pipes in the plane of the roof, through which steam will be vented. Closer to the roof ridge, holes are made with the calculation of 1 pipe per 50 sq. meters of roof. Each such element must be protected from precipitation. As a result of installing a pipe ventilation system, ventilation on the roof will become more intensive.

Video description

How to turn an attic roof without a ventilation gap into a mansard

Stages of work

The process of arranging the ventilation system of any roof consists of several main stages. The first step is to provide for the presence of ventilation elements in the scheme of the roofing system. After that, during the construction of the roof, roof ventilation ducts and openings are made. In the case of forced ventilation, special ventilation equipment is installed. At the last stage, the ventilation holes are protected from rain and dirt.

Conclusion

The roof of a private house must be well ventilated, otherwise the elements of the roofing cake will be adversely affected by condensation. They will quickly lose their original technical characteristics, and there will be a need for replacement. In addition, without high-quality ventilation of the roof, the premises of the house will be damp, and more energy will be required for heating. Therefore, it is very important to correctly design and properly build a roof with an effective ventilation system, taking into account the type of roof construction, the type of roofing material, the climatic conditions of the region and other important factors.