Roof ventilation in a private house: purpose and methods of arranging the ventilation system of an attic and attic roof. Features of a ventilated roof structure Installation of an aerator on metal tiles

Big country- large volumes of housing construction. Not only multi-storey, but also private. And every developer is important and needs knowledge on general issues construction, according to norms and rules, including those about roofing processes.

Properly executed roofing structures are the key to not only warm home and a comfortable atmosphere, but also the durability of other elements of the structure.

The roofing device is important stage construction of buildings.

Physical heat transfer processes

In a heated house, temperature changes and the presence of moisture in the air in the form of steam and condensation are inevitable. Steam is produced by human or animal activity and penetrates into building construction, cools and moisturizes them. The vast majority of building materials are permeable to some degree. Therefore, any residential building, individual or multi-apartment, is an air volume in which warm air rises upward through all structures.

In the high multi-storey buildings a traction effect appears. Warm air rises to the upper floors, this is especially noticeable in the entrances, and penetrates outside through windows and attics. On the lower floors, on the contrary, there is an influx of outside cold air. This process also occurs in a one-story heated house, only with less dynamics.

On the other hand, steam warm air condenses in structures into water, which not only moistens them, but also has the ability to flow down, filling the cavities in the structures. The main function of condensing water vapor is assumed by the top part buildings - roof. In winter, this process occurs intensively and constantly, and in summer, mainly during the cool night time.

The most modern and effective method prevent or significantly reduce moisture condensation in the roof - make it ventilated naturally or forcefully. Natural cold ventilation will not require energy costs, so its design is preferable. However, there are roofs of complex architecture that lack the strength of natural ventilation, then forced ventilation comes to the rescue.

Ventilation removes warm, moist air into the surrounding space, thereby leaving bearing structures, insulation is dry, extending service life and providing thermal insulation. We need to manage this process, which is done using the so-called roofing pie.

The concept appeared relatively recently and denotes a multi-layer roof structure, in which the leading place is given to the creation of ventilation ducts. There are two types of roofing pie: for heated and insulated rooms and for cold roof. Each layer is functionally interconnected with other layers, and the absence of any reduces the protective properties of the entire cake.

If the attic is a cold, uninsulated part of the building, it is done in several successive layers. The following tools will be required for the work.

• hammer;
• drill with drills 4-12 mm;
• wood hacksaw;
• stapler (stapler) electric or mechanical with staples 14x8 mm;
• level, meter ruler, square;
• scissors;
• screwdrivers of different sizes;
• brush-fleet for antiseptic cutting of wooden parts;
• construction sealant.

A waterproofing film (not to be confused with a vapor barrier) is laid on the upper side of the rafters. The film sag should be 20-40 mm to drain condensate. It is secured along the rafters with a counter-lattice 30-50 mm thick and a width equal to the thickness of the rafters themselves. It is better to glue the film at the attachment point with double-sided tape.

To reduce waste, the film can be laid in horizontal rows from bottom to top and with an overlap of 100-150 mm. The junctions of the strips are glued, creating a continuous web. The water generated from condensation will flow down the film to the roof eaves.

After installing the waterproofing layer, a lathing is sewn across the rafters onto the counter-lattice for roofing. The width of the boards and the gap between them are selected depending on the roofing material.

1. For ceramic and soft tiles, use an inch board 100 mm wide for the sheathing. It is laid with a gap of 50-100 mm, after which the top is completely covered with building board or waterproof plywood with a thickness of at least 9 mm. Under soft tiles The underlying layer is still being laid.
2. Lathing made of boards 30x100 and in increments of 300-400 mm is made under metal tiles or corrugated sheets;
3. For a metal seam roof, use a lathing made of an inch board 150-250 mm wide, sewn onto a counter-lattice with a minimum gap of 20-50 mm.

At the end directly onto the sheathing or building slab lay roofing material. It is attached with special nails, screws or clamps to the sheathing. The roof fastening points are protected with sealants, and the sheathing is pre-treated with an antiseptic. Additionally, you can perform rough filing along the rafters from the attic side.

Between the roof there was a ventilation gap equal to the total thickness of the sheathing and counter-lattice. This is 55-80 mm of the height of the under-roof space along the slope of the rafters. In winter, warmer attic air, partially penetrating through the waterproofing, will rise to the roof ridge and be released into the atmosphere without having time to condense moisture. And in summer, the air heated by the roof is also removed from under the roof.

Attic ventilation is important for the under-roof space. It is carried out through dormer windows, arranged on the gables with different sides. Ventilation of the living space, attic and under-roof space are interconnected, and one of their goals is to reduce steam and condensation in the roofing pie.

Ventilated insulated roof design

Often attic space used as an attic, insulated from the roof side. In this case, several more layers are added to the roofing pie. Now there is no attic between the living space and the roof air gap. Warm and humid attic air immediately penetrates into the under-roof space. And if additional measures are not taken to remove it, there will be much more condensation and the structures will begin to get wet. Thermal insulation materials will cease to perform their functions and the air in the room will be cold. We'll have to turn up the heating.

In addition to those layers that are already made in cold roof, add thick layer insulation placed between the rafters with inside. If ordinary rafters are 150 mm wide, then the thickness of the insulation between the rafters can be no more than 100 mm. The reason is the need to leave a minimum gap (do not touch) until the waterproofing sag, which reaches 40 mm. If there is a touch, water flowing down the insulation will get into the insulation. To increase the thickness of the layer, timber is sewn onto the rafters required thickness and add insulation.

Then it is closed vapor barrier film. The goal is to minimize the penetration of steam from the room into the insulation so that it does not get wet. Wet insulation is no good, it does not retain heat and, in addition, moisturizes the surrounding structures. First, a rough lining is sewn onto the vapor barrier, and then a finishing lining.

Now the path of wet steam to the roof is blocked, and although a small part of it still penetrates, it is carried out into the atmosphere by the under-roof ventilation air flow, without causing harm to the roof structures. And if by itself warm room not ventilated, where will the steam go? Through all sorts of microscopic pores and cracks it will still go up to the roof. This will also be facilitated by the excess pressure generated in the warm attic room.

Ventilation of the room itself will help relieve excess pressure, reduce the moisture content in the living room and thereby help under-roof ventilation remove moist air into the atmosphere.

Ventilated cornice device

The longitudinal ventilation channels of the roofing pie will not work effectively if, on the one hand, in the lower part, at the very eaves, there is no inflow atmospheric air. On the other hand, it is necessary to allow the humidified air to escape from the very top part of the roof - from the ridge.

Waterproofing film is the strongest of all types of films used in home construction, so it does not allow water or moisture to pass through, even under high pressure.

The waterproofing film is removed and glued with sealant to the metal cornice strip installed in the plane of the sheathing. The roof is fixed on top. Air flow is carried out in 3 ways. Firstly, through the gaps of the profile of the roofing material, secondly, through the gable overhangs and, thirdly, through the micropores of the waterproofing film, drawing vapor from the insulation.

When covering the cornice in its lower part, it is provided ventilation holes or gaps depending on the many design options for the cornice. One of modern methods- this is a continuous filing of the cornice plastic panels with perforations for roof ventilation.

Creating a ridge hood

Depending on the design of the roof covering, the air flow from under the roof is collected in the ridge and discharged into the atmosphere either through structural gaps along the length of the ridge, or through gable openings. For example, complete with ceramic and metal tiles There are special ridge elements with ventilation gaps. Additionally, there are additional elements for non-standard shape skate.

This outer part roofs. The internal structure is performed in a certain sequence.

• the counter-lattice along the rafters is not brought to the geometric height at the same distance of 20-40 mm. The bars of the oncoming slopes do not join;
• sheathing in 2 solid boards from both slopes on the ridge is also performed with a longitudinal gap of 40-80 mm;
• waterproofing film cut along the ridge with a margin of 200 mm for hems on both slopes;
• between the ends of the counter-lattice and the sheathing along the ridge it is installed vertically ridge beam 40x100 mm;
• a waterproofing sheet is attached to it and sealed with sealant;
• From above this structure is covered with a ridge according to the instructions and technology;
• Install ridge end elements on the gable side, in which ventilation holes or gaps are provided.

Some features of a ventilated roof

Roof ventilation is not an independent process. On the contrary, ventilation or its absence in the premises directly affects the air exchange in the roof. In order to effectively remove destructive moisture from residential premises through the roof, it is necessary to consider the ventilation of all building elements as a single process.

If the shape of the roof is complex, has many transitions, valleys, ventilation processes must be divided into sections and air flows in the roof must be formed separately. As a result of effective ventilation, the air in the under-roof space should be replaced approximately 2 times within an hour.

The effectiveness of a ventilated roof depends on the slope of the slopes. The steeper they are, the stronger the ventilation process occurs. And, conversely, in roofs with a slope of less than 20%, under-roof ventilation is unstable and effective only under wind pressure.

Always is useful device on the roof of additional exhaust elements (aerators), helping to strengthen natural ventilation roofs. They should be placed on roofs of complex shapes, when conventional means are no longer sufficient. Aerators are installed near the ridge.

The thermal insulation properties of insulation and the durability of roof structures directly depend on the presence of moisture in them. Therefore, a ventilated roof and the design of room ventilation are economically beneficial even when it is necessary to install forced air exchange.

Formed on the elements roofing structure condensation can cause premature failure. This problem is especially relevant during the period heating season, with a significant difference between the temperature outside and inside the building. In this case, the insulation experiences a serious load, the range of values ​​​​can reach tens of degrees, as a result of which drops of moisture settle on it, blocking thermal insulation properties material.

The best way to resolve the issue is to install a house roof with ventilation. IN winter period it will ensure effective thermal insulation and, in the summer, reduce discomfort due to heat by preventing the flow of heated air. The costs of arranging the roof will increase slightly, but already in the first years of its operation they are guaranteed to pay off.

Ventilated roof design

The main goal when designing a ventilated roof is the choice of building materials. Others will need to be taken into account important points: number of gaps for air passage, lathing pitch, type of waterproofing film and other nuances. Thus, when using materials with polymers, the ventilation space must be larger than when installing natural roofing.

The main task of a ventilated roof is to ensure air circulation and prevent the formation of 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 roofing:

• non-insulated, main scope of application – utility and industrial buildings;
• insulated - used at all facilities where people are long time: housing, commercial and administrative buildings, other buildings.

Main elements of a ventilated roof:

• rafter system;
• sheathing;
• waterproofing;
• insulation (not on all objects);
• roofing covering.

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 circulates. One of the options for ventilating a roofing pie is to use thermal insulation material with channels for air flow. It does not matter whether 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 can 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;
• the coating's resistance to most external factors increases: precipitation, extremely low or high temperatures, rotting and so on.

Using a ventilated roof is one way to extend the life of the roof covering, avoid the formation of 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 take a responsible approach to choosing a company that can be entrusted with such work.

Today, the most popular various designs roofs, which differ not only in the complexity of the device, but also in the roofing pie, characteristics, and installation methods. Among these various types V separate group there is a ventilated roof, which has excellent protection against swelling of the roofing carpet, wetting of the cake, the appearance of mold and mildew.

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 wet insulation and rafter systems. In our article we will look at the structure of such a roof and its features that made them so popular in private construction and construction apartment buildings, industrial, utility buildings. In addition, we will find out what options for such a roof exist, and how exactly they differ from each other. Our specialists will share the secrets of installation, which you can do yourself without calling a team of professional builders.

Ventilated roof design

Ventilated roofs, the designs of which are quite simple, include the following basic components necessary to ensure ventilation, such as:

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

It is the features of the location of ventilation that distinguish such a roof from others, constant tributaries air allows not only to effectively remove moisture outside, but also to control the temperature level. In this case, ventilation will greatly depend on whether the roof sheathing system is installed correctly.

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

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

• rafter system;
• sheathing;
• waterproofing;
• roofing material.

The waterproofing film is attached to the rafters with slats; it prevents moisture from getting inside and extends the service life of the roof. But such a design is cold, that is, there is no thermal insulation layer in it. This is not suitable for private residential buildings; here it is necessary to arrange a different roofing pie. In addition to the listed layers, in this case you need slab insulation and an anti-condensation film that prevents condensation from forming on the roof elements. This material consists of several layers:

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

In addition, the installation of a ventilated roof requires the presence of vents in the lower part of the eaves and ventilated ridges.

Advantages of a ventilated roof

Ventilated roofing differs from other structures in the following advantages, which put it in first place:

1. Installation of such a roof is possible even with sub-zero temperature, the only exceptions are the presence of heavy rain, heavy snowfall, frost, which drops below minus twenty degrees Celsius.
2. During reconstruction, the removal of old roofing is minimal, including preparatory work; This makes it possible to save money and time on installation; the cost of the roof is much lower.
3. During further operation, all roof elements are completely dried, including floor slabs, heat insulation, and old roofing (if any remains). This allows you to completely remove the risk of rot, mold, mildew, which are very dangerous for general design roofs.
4. 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.
5. The swelling of the roofing carpet is completely eliminated.
6. The durability 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, various mechanical damage.

How to design ventilation correctly?

Designing such a structure always requires careful preparation. When implementing a project, it is necessary to ensure that:

• water from the surface always flowed down, that is, it must be created correct protection from her influence;
• steam rushed upward from the premises, that is, the presence of vapor protection is also mandatory.

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

Ventilated roof options

Today the most Various types ventilated roofs, 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. Let's look at these two main design options, their differences, device diagrams, advantages.

Flat roofs

Such flat roofs began to be used in the early eighties, when it became possible to use thermal insulation 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 there was the end of a ventilation pipe, the so-called aerator, which removes excess moisture;
• cement-sand screed;
• waterproofing layer made of bituminous materials;
• polyurethane material;
• a layer of polyurethane mastic;
• roofing material.

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

Pitched roofs

Pitched roofs differ from flat ones in that air flows enter through the lower overhangs and exit through the ridge, and with them all excess moisture that accumulates under the roof space in the insulation is removed. Ventilation in this case can be forced, for which purpose they are installed roof fans, the coating is recommended to be light, preferably having a wavy texture. The roof can be insulated or non-insulated; the roofing pie differs only in the presence or absence of a heat insulating layer. Residential buildings require insulation; in this case, mineral wool in the form of slabs is excellent; they are very easy to install, provide an insulated coating, and the absence of cold bridges.

Installation

The ventilated roof is installed in the following order:

1. Preparing the base for work, including eliminating cracks and potholes. This could be a normal setup. cement mortar, leveling the entire surface, or paving the slab. It must be remembered that minimum slope such a roof should be between two and three degrees!
2. Next comes the laying of a layer of vapor barrier film and insulation, in which stripes and cracks are unacceptable. Most often used for this mineral wool or glass wool, which guarantee excellent quality and low installation costs.
3. Depending on the type of roof, further installation work may vary, but basically a waterproofing layer and cement screed are laid.
4. Roll fused materials are used as roof coverings, which provide excellent quality. Installation is carried out using gas burner, in this case the bitumen melts, the material itself is firmly glued to the base. The lateral overlap should be from one millimeter to five.

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

Constant changes in temperature outside the house, rain and melt water lead to the formation of condensation, which has a destructive effect on the roof truss system. Moisture is absorbed by the insulation and over time it ceases to perform its function. A ventilated roof structure is the only effective way to prevent the accumulation of moisture in the under-roof space and prevent deformation of load-bearing elements.

Advantages of a ventilated roof

The source of condensation can be not only external factors, but also internal vapors generated as a result of human activity. Ventilated structures have been used in construction for quite a long time and the effectiveness of the technology has been tested by many years of practice:

• When constructing a ventilated roof on a previously used building, there is no need to dismantle the old roofing, as a result of which the cost of work and the time it takes to complete it are significantly reduced.
• The technology allows work to be carried out at temperatures down to -20°C. The only contraindication is the presence of precipitation during installation.
• Free air circulation in the under-roof space ensures drying of all ceiling elements and prevents the formation of fungus and rotting of damp wood.
• A properly executed ventilated roof is resistant to mechanical stress, frost, temperature fluctuations and ultraviolet radiation.

When erecting a ventilated roof over an old covering, its functionality is restored due to the complete drying of all elements. The result is a double design, which increases thermal insulation characteristics the buildings.

Ventilated roof installation

A ventilated roof involves the construction of a roofing pie - a multi-layer structure that prevents heat losses At home in winter time, and in summer it prevents the heating of the room from the hot roof. In addition, it protects the insulation from the penetration of water vapor from inside the room and removes it outside in the event of penetration. The roofing cake also protects the inner surface of the roofing material from the damaging effects of vapors. For this simple insulation not enough, the roof must be ventilated. All layers of the pie are interconnected with each other and the absence of any reduces the effectiveness of the entire structure as a whole.

Roofing pie installation from bottom to top:

• interior decoration;
• vapor barrier;
• insulation layer;
• bottom ventilated gap;
• waterproofing;
• top ventilated gap;
• roofing covering.

Ventilated gaps between the layers of the roofing cake provide drainage humid air beyond the structure and supports temperature regime on the same level. Ventilation can be natural or forced, in the case of a complex roof configuration. On buildings technical purposes or garages, they make an uninsulated version of a ventilated roof, which lacks insulation and a vapor barrier layer.

Construction of a pitched ventilated roof

First of all, you need to decide on the type of roofing. The type of waterproofing film, the number of blown gaps, as well as the design of the lathing and counter-lattice depend on this choice. Depending on the selected coating and climatic conditions of the region, the cross section is calculated rafter legs and their step. This is a critical stage that requires high precision, since if the loads are calculated incorrectly, the structure may deform or even collapse after some time.

After constructing the rafter system, it is necessary to select the type of waterproofing film, which also depends on the roofing material. There are several varieties on sale, differing in operating principle and cost:

• Superdiffusion membranes- the most expensive and most practical option. The material is impermeable to water, but at the same time permeable to steam. This unique ability allows superdiffusion membranes to be installed close to thermal insulation without creating a lower ventilated gap. This type of waterproofing implies restrictions on the use of certain roofing materials. This applies to coatings whose inner surface does not tolerate prolonged contact with water vapor, for example, metal tiles and wavy bitumen sheets. Paired with cement-sand, bitumen or ceramic tiles The material is functioning normally. The superdiffusion membrane is fastened to the rafters using counter-lattice slats. A sheathing for the roof covering is mounted on top, forming a ventilated gap. Water vapor escaping from the insulation passes through the membrane into a ventilated gap, from where it is removed outside the structure.
• Diffusion membranes- perform the same function, only for them normal operation two ventilated gaps are required. The material is plastic film with many microscopic holes. If they come into close contact with the insulation boards, they may overlap and the membrane will simply stop working. Like the previous type of waterproofing, the material is not intended for use with coatings whose back surface is not resistant to moisture.
• Anti-condensation films- a vapor-permeable material, the use of which can be paired with coatings that do not get along with previous types of waterproofing. WITH reverse side facing the heat-insulating layer, the material has a fleecy surface on which vapors escaping from the insulation are retained. In this case, the arrangement of two ventilated gaps is required condition for the normal functioning of the material. Moisture from the pile is carried away by air through the lower gap, while the inner surface of the roofing is reliably protected from evaporation and is continuously ventilated thanks to the upper ventilated gap.

The use of anti-condensation films is also beneficial from an economic point of view, since it allows you to extend the service life of inexpensive metal tiles, which is usually 10-12 years. A properly executed ventilated design will increase it by 1.5-2 times.

When constructing ventilated systems using anti-condensation and diffusion waterproofing materials, it is necessary to ensure that they are installed correctly. If you accidentally mix up the sides, the material will turn into an ordinary film with all the ensuing consequences.

On next stage a thermal insulation layer is installed. Experts recommend selecting a material with high vapor permeability, allowing truss structure breathe, causing its integrity and load bearing capacity lasts longer. Mineral wool insulation materials fully possess this characteristic.

On the inside of the attic, the thermal insulation is covered with a special vapor barrier film, which serves as a barrier to vapors from the room. As budget option for a vapor barrier you can use glassine or reinforced polyethylene, used for the construction of greenhouses. There is also a film with a reflector made of metal spraying. It improves the thermal insulation characteristics of the room, but when installing it, it is necessary to leave a gap of 20 mm, which will complicate the design a little. The vapor barrier layer is sewn up with finishing material.

Flat ventilated roof

A flat ventilated roof has a simpler structure, since its construction does not require a complex rafter system. Air circulation, which ensures the removal of water vapor, is achieved due to the gap between the layer of waterproofing and insulation.

Layer arrangement from bottom to top:

• bottom floor;
• vapor barrier;
• heat-insulating layer;
• ventilated gap;
• top floor;
• roofing material.

Flat roofs are more susceptible to precipitation, so they must be installed with a slope of at least 5°, but not more than 20°. Wood is mainly used as a material, but the use of reinforced concrete slabs is also possible if the design of the house allows it. Fused roofing materials are often used for covering.

Ventilation of the under-roof space is carried out through openings located on the external walls. Their total area must be at least 1/500 of the entire roof surface. It is worth noting that a vapor barrier layer is only necessary if the base is used wooden floor. If this reinforced concrete slab, then the insulation is attached directly to it using glue or special mechanical fasteners.

Arrangement of ventilated space on flat roof helps prevent the formation of bubbles and subsequent ruptures of the coating as a result of the pressure of accumulated water vapor. The service life of a well-made flat ventilated roof is several decades.

Almost every person who builds a house should know what a ventilated roof is?

It consists of three main ventilation circuits:

1. ventilation of the space, which is located between the waterproofing layer and the coating, and also covers almost all planes, despite the degree of complexity of the roofs;

1. ventilation of the space directly under the roof, which is considered one of the elements of the home ventilation system;

1. ventilation of the space located between the waterproofing layer and insulation, in which stagnant zones are absolutely excluded.

Ventilation design and installation

For many decades, with imperfect technologies and building materials, houses were built that breathed through brick, wood, window cracks, doors, masonry, and cracks between layers roll materials- roofing felt, glassine, in which all three ventilation circuits were united.

As a result of these technologies, the house had constant drafts, increased heating costs and some restrictions on the finishing of the premises. Quite often dampness and fungus appeared in some places. Ventilation ducts in houses they were located only in kitchens and bathrooms.

This issue was resolved by high level modern Construction Materials for the roof.

For your attention! When designing your home you should Special attention be given to the ventilation system.

For those who want to independently examine the project, there are two basic rules for a warm roofer:

• Steam always rushes upward

• Water always flows down.

The consequences of these rules are as follows:

When installing a vapor barrier, there is little overlap of roofing materials on each other, on load-bearing elements and the walls of the structure and the joints are taped with a special tape;

When there is no indoor ventilation, sometimes even gluing cannot prevent moisture from penetrating into the insulation if the vapor pressure is high. Ventilation allows “steam to escape from the boiler.”

The walls of the house should not “breathe”, since moisture, which is retained in the outer layers of the walls, often leads to delamination when frozen and easily penetrates through the walls into the “roofing pie”.

Tip! Pay attention to ventilation small rooms and spaces.

Installation of vapor barrier should be carried out closer to the interior of the house.

If errors occur during the installation of waterproofing, then it is necessary to dismantle the roof covering, correct the errors, and provide access from inside the house to the vapor barrier.

Roofing device

Roof ventilation prevents the formation of ice crust on the ridge and roof ledges.

Inflow fresh air provides a ventilated space, and in the summer, when the roof heats up, the air picks up moisture and removes it outside. For such a system to work well, it is necessary to carefully think through the sheathing on which the ventilated roof is applied.

If the rafter system has already been installed, then it is worth thinking about choosing a roof. If you are building premises such as a garage or warehouse that are not heated, then the ventilation in them will be natural and the service life of this building will be limited by the service life of the selected materials.

In order for a building to last a long time, it is necessary to arrange forced ventilation and insulate the room.

An uninsulated roof consists of the following elements:

• rafters;
• lathing;
• roofing material;
• waterproofing films.

The waterproofing film is fixed to the rafters using slats. Even when the roofing covering wears out, it protects against moisture from entering the building and has a long service life.

Such material will be indispensable even if you build a small country house, covered with slate, this film will last more than 50 years.

In private homes, a special “” device is required.

In addition to insulation, a diffusion waterproofing film is applied for ventilation. This film does not allow moisture to pass into the under-roof structures and ensures the passage of steam through the smallest pores of the material.

It also reliably protects the structure from the wind, having excellent waterproofing properties.

Only when installing gaps between the heat-insulating structure, roofing and film, good ventilation is ensured by the use of diffusion film for waterproofing. Otherwise, it will not allow water vapor to pass through.

You can use anti-condensation film for waterproofing.

It will prevent the formation of condensation well and is used for constructing a ventilated roof when using any roofing covering.

The structure of this material consists of 4 layers:

• ultraviolet resistant polypropylene fabric;
• non-woven moisture-absorbing material;
• laminated film – 2 layers.

Anti-condensation film protects not only from the penetration of moisture into the room, but also from the accumulation of dust and the formation of soot.

In a ventilated roof, vents are left to achieve a good effect, and also holes and ventilated ridges are installed in the lower part of the eaves, which well connects the ventilated gaps of the roof with the atmosphere.

The ventilated roof structure consists of finishing material and roof insulation. The steam that leaves the room reaches the insulation, which, absorbing moisture, loses its thermal insulation qualities.

The moisture that has accumulated in the thermal insulation layer mainly penetrates back into the room and appears in the form of drops on the ceiling and walls.

And in the summer it heats up very quickly and the heat enters the room through the roof structure. To avoid this, this is why a ventilated roof is installed.

Today the requirements for modern roofing materials very tough. They should protect the room from moisture penetration into the layer, and if this happens, then facilitate the rapid removal of moisture to the outside.

Therefore, a ventilated roof must be well insulated.