Roof aerator: device and installation of ventilation elements of the under-roof space. Installation of aerators on a soft roof: models and installation schemes Calculation of the number of aerators on a flat roof

25.11.2019

One of the mandatory elements of ventilated roofs is roof aerator, which is installed to remove water vapor and moisture accumulating in the under-roof space. The number of aerators on a flat roof depends on its area, as well as on technical features devices selected for installation. In accordance with the requirements of building codes for every 100 sq. m of the roof surface should account for one fan. For installation, the most elevated points attributable to the junction of heat-insulating plates are selected. Thanks to the installation of deflectors, it is possible to increase the life of the waterproofing carpet, as well as to prevent the appearance of blisters on the surface of the soft roof during temperature changes. On pitched roofs covered with metal, flexible (bituminous), ceramic or cement-sand tiles, ventilation devices are installed as high as possible, but at the same time they do not reach the ridge closer than half a meter.

Experts have found that during the operation of soft roofs, the main disadvantage is the accumulation of excess moisture in the insulation and screed. Increased hydration of these layers roofing cake causes a number of negative consequences, namely:

Blisters in the roofing that appear as a result of heating the soft roof in summer time due to the delamination of bitumen-polymer materials under the influence of high temperatures.
An increase in thermal conductivity provokes moisture accumulated under the waterproofing, which worsens the thermal insulation properties. Theoretically, it has long been proven that with an increase in the level of moisture by 1-2 percent, an increase in the coefficient of thermal conductivity by 30-40 percent occurs. This leads to an increase in the cost of heating the facility. In addition to heat loss, waterlogged roofing layers can lead to mold growth.
The destruction of the waterproofing carpet and the cement-sand leveling screed is caused by the ingress of moisture into the pores of the material. After the ambient temperature drops, the crystallization of the water that has penetrated into the pores occurs and its volume increases. This process is accompanied by the appearance of microcracks and the destruction of the leveling screed. Similar negative processes occur in the waterproofing layer, violating its integrity.

What does a roof ventilation device look like?

The roof aerator promotes an exit of water vapors from under a roof surface

The roof aerator is made of pipes, the diameter of which can vary from 63 to 110 mm. From above, the pipe is covered with an umbrella, which prevents precipitation from entering the fan. These devices are made from the following materials:

AISI 316 stainless steel;
polypropylene.

These materials provide the aerator with resistance to ultraviolet rays and atmospheric precipitation, corrosion damage and mechanical stress. Roof fans are used in different climatic zones. They can be operated at temperatures ranging from -50 °C up to +90 °C. Even plastic aerators are able to withstand the short-term action of the flame of the burner used when laying rolled bituminous materials.

Manufacturers produce aerators of various shapes and purposes.

Important! These devices can be installed not only when installing new roofs, but also when performing current repair old roofs. At the same time, it is possible to save on the costs of operating the roof.

Installation of aerators for the construction of new roofs

When laying a new roof on a base made of reinforced concrete floor slabs, plastic aerators are installed on the bottom layer of the material. In this case, the work is performed according to the following algorithm:

in the intended installation location of the fan, a hole is cut in the screed layer, insulation, reaching the vapor barrier layer; hole diameter is from 80 to 120 mm;
expanded clay is poured into the resulting hole;
apply mastic, glue or sealant to the horizontal part of the aerator to ensure better adhesion of the device to the roofing carpet;
wait for the mastic, glue or sealant to harden and carry out additional fastening of the fan using six self-tapping screws screwed around the entire circumference of the pipe skirt;
then, the upper layer of the roofing carpet is fastened, while the aerator should be in the place of the end overlap of two adjacent roofing sheets (overlap width - 150 mm);
roofing material at the place of installation of the aerator is laid freely;
then it is necessary to fuse (apply or spray, depending on the chosen technology) a patch from the upper layer of the roofing material on the place where the aerator and the roofing mat meet in such a way that it overlaps the skirt of the device and enters the roofing carpet at a distance equal to at least 150 mm.

Aerators are selected depending on the purpose

If the device of a soft roof will be carried out in one layer, then the aerator must be installed directly on the screed.

When installing deflectors in a roof with a base made of profiled sheet, you can follow the rules described above. However, there are slight differences, which consist in the fact that the hole in the intended installation site of the roof aerator must pass through the top layer of insulation to the bottom layer of thermal insulation. Then the ventilation device is fixed with long self-tapping screws to the profiled sheet through the insulation or directly into the heat-insulating plate itself.

Important! When performing current repairs of the old roof, a hole with a diameter of 80 to 120 mm is cut in the carpet. Depending on the number of layers, the hole extends to the vapor barrier layer or to the screed. After that, the aerator is installed with the application of mastic and subsequent fixing with self-tapping screws. The work is completed by applying the top layer of the welded roof.

Installation schemes for roof aerators

Schematic arrangement of a traditional unexploited roof on which the ventilation device is installed:

Traditional unexploited roof with aerator.

expanded clay layer;
vapor barrier layer;
thermal insulation layer;
leveling screed;
bottom waterproofing layer;
top waterproofing layer;
roof aerator body;
protective umbrella.

Scheme of an unexploited roof, which incorporates one layer of waterproofing:

Scheme of an unexploited roof with one layer of waterproofing.

expanded clay layer;
plates reinforced concrete floor;
vapor barrier layer;
thermal insulation layer;
leveling screed;
waterproofing layer;
roof aerator housing;
protective umbrella.

Schematic arrangement of a traditional operated roof, on which a ventilation device is installed:

expanded clay layer;
reinforced concrete floor slab;
light concrete slope;
vapor barrier;
thermal insulation layer;
leveling screed;
waterproofing layer;
washed gravel;
protective umbrella;
roof aerator body.

Schematic device of the inverted roof, on which the ventilation device is installed:

Inverted roof with aerator.

expanded clay layer;
reinforced concrete floor slabs;
light concrete slope;
vapor barrier layer;
thermal insulation layer;
leveling screed;
waterproofing layer;
drainage;
backfill of washed gravel;
top coat of paving slabs;
protective umbrella;
roof aerator body.

Conclusion

The need for installation ventilation system depends on the complexity of the shape of the roof and its dimensions, as well as on the state of the vapor barrier and the degree of air humidity in the interior. When installing several aerators, a distance between them of 12 m is maintained. On roofs with a pronounced valley line and a ridge, aerators are installed along the ridge and in the valley on the watershed. For objects operating in conditions of high humidity (laundries, baths, saunas, swimming pools), perform an accurate calculation of installation points ventilation devices should be engineers of design organizations.

A well-planned roof must have aerators

It is also better to trust the installation of ventilation systems and their individual elements to professional companies that have mastered the intricacies of the technology for performing these works. Self installation carried out with errors will only aggravate the condition of the roof. If the roofing carpet is destroyed, the repair costs may not be comparable to the wages of professional roofers.

All roofs with a rigid internal frame have one thing in common - condensate periodically accumulates in the internal passages and threatens the supporting structures with premature decay and destruction. In this article we will talk about such a useful invention as a roof aerator, which provides ventilation and maintenance roof structures dry.

Soft roof application

Please note that the installation of the aerator is possible even on flat roofs. In case of soft roof Roof aerator prevents material swelling. The principle of operation of this simple mechanism is to remove moisture until it crystallizes under the roofing material. Thus, no delamination occurs. soft cover from the frame structure.

Ideally, the installation of aerators on a soft roof should be carried out simultaneously with the construction of the house. This will save you from the occurrence of mold and rotting beams on the roof. However, even if these devices were neglected at the beginning of construction, they can always be installed later - this is not at all difficult to do.

Soft roofing is currently quite popular and actively used roofing material. It is laid on a reinforced concrete base, on which layers of insulation, waterproofing and a cement-sand screed are applied. As a rule, the waterproofing layer is represented by rolled materials.

Why you need a roof aerator

Depending on the quality of work on waterproofing and insulation, as well as laying a soft roof, its service life may vary. Among the most common defects of such roofs is the accumulation of condensate in the insulation layer and screed. This problem can be eliminated just with the help of a roof aerator. It allows you to reduce the moisture content in the roofing cake and prevent its further accumulation. Therefore, many reasonably believe that thanks to these devices, it is possible to significantly extend the life of a soft roof.

The formation and accumulation of condensate can eventually lead to the following consequences:

Flat roof swelling.
Increase in thermal conductivity.
Defects in the screed or roofing cake.

The most common problem is the swelling of the roof, the causes of which may be:

Temperature increase in summer period leads to heating of bituminous materials and changes in their structure, namely, an increase in plasticity. In this case, the degree of viscosity of the mastic on which the roofing material was laid will matter.
Accumulation of steam in the space under the roof. Since the roofing pie consists of a lower vapor barrier and an upper waterproofing layer, when the temperature rises, the liquid accumulated between them is converted into steam, creating excessive pressure.
Delamination of roofing cake and bitumen-polymer composition. To get rid of the swelling of the coating, the waterproofing must be carefully glued to the base. In addition, you can use the roof aerator.

An increase in thermal conductivity entails significant heat losses and additional energy costs. According to studies, an increase in roof moisture even by 1-2% causes an increase in thermal conductivity by 30-40%. In addition, warm and humid environments favor mold growth.

As for the destruction of the screed, then the reason lies in the porosity of the material. In the normal state, the pores in cement mortar filled with air. With excessive moisture in the roof, these pores begin to fill with condensate, which expands as the temperature drops and leads to the formation of cracks and defects in the screed. In this case, the waterproofing layer may also be affected.

When choosing plastic aerators for the roof, in each case it is necessary to determine what caused the increase in humidity.

Causes of increased humidity in the under-roof space

Moisture ingress into the insulation can occur from the external environment due to defects and malfunctions in the roofing pie. In addition, it can also accumulate due to the destruction or damage of the vapor barrier layer. One of external factors wetting of the insulation can be difficult weather conditions and high humidity air.

In cases where the insulation layer accumulates too much water and, therefore, does not have time to fully dry out, it will not be easy to cope with the problem without additional devices. A similar situation is observed in the case of roofs that are constantly wet. In this case, it is almost impossible to achieve positive results.

In the end, you will have to replace the insulation, for which the roof will need to be almost completely disassembled. This process will require too much material and labor resources, which not every owner can afford.

To save money, you can get rid of excess moisture in the roofing cake by evaporation. In this case, all the complex and expensive work on dismantling the roof and replacing waterproofing and insulation will simply not be needed. In addition, thanks to drying, it will be possible not to be afraid of the occurrence of leaks, which, as a rule, occur after roof repairs.

Alternatively, you can use an aerator for ventilation. The operation of such devices is carried out due to the difference between the internal and external pressure of air masses. Thanks to this principle, draft arises in the aerator tube, which is created due to a decrease in pressure under the influence of wind currents from the outside.

To understand why you need a roof aerator, here are the main functions of this device:

The removal of air saturated with steam coming from interior spaces out. This process occurs constantly, therefore, moisture does not have time to accumulate on the frame structure.
Decrease in internal pressure in the thickness of the roofing cake, due to which, as a rule, swelling of the finishing roofing material occurs.
Prevention of liquid crystallization and its accumulation in the lower part of the waterproofing layer. Otherwise, condensate penetrates into the thickness of the insulation and leads to the loss of its qualities by the material.

By design, an aerator for a roof made of metal or any other material is a pipe with a cross section of 63 to 111 mm. An umbrella is installed over the pipe so that precipitation does not fall into it. As a rule, a roof aerator is made of polyethylene pipes HDPE.

Rules for installing aerators for the roof

The technology for installing roof aerators consists of several steps:

In the thickness of the screed for installing a ventilation pipe, a window is cut through. Its depth should reach the inner layer of insulation.
The condition of the insulation should be checked - the wet material is removed and replaced with a dry one so that its thermal conductivity meets the requirements of the standards.
Now they are fixing the aerator pipe. To do this, first a layer of mastic is applied to its lower part, and then it is screwed to the cement screed using six self-tapping screws. Screw the screws into the aerator skirt at the same distance from each other.
To prevent water from seeping under the device, an additional layer of waterproofing is laid on the base of the ventilation pipe.

To understand whether an aerator is required for a metal roof in each specific case, it is worth considering a number of factors. In particular, the type of construction and size of the roof, the level of humidity in the premises, as well as the reliability and condition of the vapor barrier layer of the roofing pie are important.

For houses with flat roofs that do not have complex lines and are manufactured in compliance with all building standards, the norms for the number of aerators on the roof suggest the installation of one device for every 100 m 2.

However, the distance between individual aerators should not exceed 12 meters. On roofs where the valley and ridge are clearly marked, the installation of ventilation pipes should be carried out along the passage of the ridge and in the valley itself at the watershed boundary.

Please note that if it is originally planned to use the building in a permanent high humidity, for example, for saunas, baths or swimming pools, then special design offices should deal with the calculation of the number and location of aerators.

Of course, the installation of roof aerators can be done independently if you have at least minimal skills in construction. However, you can also use the services of professional builders who will do everything quickly and efficiently.

How roof ventilation works

As it has already become clear, the design of the aerator does not provide for any mechanisms that would remove excess moisture from the roofing pie. These devices are something like ventilation ducts that provide air exchange. Unhindered hit fresh air into the space under the roof helps to remove excess moisture and maintain the humidity level within acceptable limits. Thus, the main task of aerators is to ensure the flow of air under the roof without interference.

The functionality of the device is maintained in all weather conditions. The fact is that the humidity of freely circulating air will in any case be lower than that of air masses that are concentrated in a closed space under the roof. Ventilation pipes can ensure that excess moisture from the outside does not enter the under-roof space, and excess moist air can freely leave the roof.

It is obvious that the provision good ventilation roofs are feasible. All you need is to install a roof aerator. So you can be sure that moist air will not stagnate under the roof, but will be able to circulate freely.

It is noteworthy that the roof aerator does not need special care - you just need to check if the passages are clogged. In general, this is a very simple and reliable device that successfully solves the problems of excessive moisture and allows you to extend the life of any roof.

Product Description:

Roofing aerator TechnoNIKOL 160x460 mm, black, is made from a block copolymer of ethylene and propylene, which provides high reliability and resistance to environmental influences on the roof. Provides reliable operation for 25 years.

Roofing aerator TechnoNIKOL ECO 160x450 mm, dark brown, has a smaller wall thickness and is made from a mixture of polymers that provide resistance to operational loads for 15 years.

Roofing aerator TechnoNIKOL ECO 75x340 mm, black, made from a mixture of polymers and is used only for roof repairs.

Plastic aerators have additional UV protection, which allows them to be used in all climatic zones of Russia.

Application area:

Roofing aerators TechnoNIKOL 160x460 mm and TechnoNIKOL ECO 160x450 mm allow you to effectively remove excess moisture from the roofing pie. The installation of aerators prevents the formation of blisters under the roofing material, which significantly increases the life of the roofing. Installation of aerators when installing or repairing a combined roof further increases the effectiveness of mineral wool insulation by reducing its moisture content.

In systems with mechanical fastening of the roofing mat to the base, it is recommended to install one aerator per 150m2 of roof. The most optimal is the placement of aerators in the roof ridges at a distance of 6-8 meters and at the highest points along the valley (funnel lines).

At least 1 aerator per 100 m 2 is installed in roofs laid on cement-sand screeds using Uniflex EPV Vent and Technoelast EKV Vent materials. Aerators are installed evenly over the surface of the roof. The arrangement is considered optimal when most of the aerators are installed in the watershed and the distance between the aerators does not exceed 12 m, and the distance to the vapor barrier structure (parapet, expansion joint, wall) does not exceed 6 m.

The design of aerators implies an additional possibility of insulation with expanded clay gravel. This eliminates the freezing of the roof at the place where the aerator is installed and the formation of an excess amount of condensate on its walls.

Roofing aerator TechnoNIKOL ECO 75x340 mm can only be used for roof repairs. The aerodynamic shape and reduced flow area allow it to work only after a sufficiently strong heating of the roof. It is installed 1 per 100 m 2 regardless of the method of roof installation and only prevents the formation of blisters under the roof. Its design does not imply additional insulation with expanded clay gravel.

Roof aerators are forbidden to be installed in combined roofs above refrigerators and ice arenas.

Manufacturing jobs:

Installation of aerators and requirements for their installation are described in the instructions for use given on the packaging. Can be used in all climatic regions according to SP 131.13330.

Storage:

In a warehouse protected from rain.

Transportation:

Transportation is carried out by all types of transport in covered vehicles in accordance with the Rules for the carriage of goods in force for this type of transport.

Packing Details:

Roofing aerator TechnoNIKOL 160x460 mm - code EKN 34591, roofing aerator TechnoNIKOL ECO 160x450 mm - code EKN 39091, roofing aerator TechnoNIKOL ECO 75x340 mm - code EKN 5489.

Only for the first unprofessional look it may seem that the roofing pie is a simple and understandable design. In fact, various physical processes take place inside the roof, which can shorten the life of the roof, regardless of the quality of the materials used. It is very important to properly organize the work of the roof and under-roof space. Therefore, the roof aerator (wind vane) today has become an integral part of a huge number of roofs.

To begin with, it is worth understanding what physical processes we are talking about:

Thermal expansion of materials. All solids and liquids expand when heated. This is explained by the fact that when heat is absorbed, the molecules begin to move more actively, which leads to an increase in the interatomic space and an increase in the volume of the body. For all materials, an indicator such as the coefficient of thermal expansion is used, which, in turn, is divided by the coefficient of volumetric and linear expansion.
vapor permeability of materials. Almost all solids pass steam. Steam is the gaseous state of liquids. The ability to pass steam is characterized by such an indicator as the vapor permeability coefficient.
Condensate. It is a liquid that is formed when a gaseous substance is cooled. Drops of water settle in the roof from moisture-saturated air at a certain temperature. The temperature at which condensation begins to form is called the dew point. The higher the air humidity, the higher the temperature at which condensation forms.

All roofs can be divided into pitched (coated with slate, steel sheets, tiles) and flat (made of built-up bituminous materials). These roofs differ in the structures, materials and technologies used.

pitched roof

A pitched roof is a roof with a sloping surface. A flat roof also has a slope, only the angle of inclination is about 1–4 degrees. For a pitched surface, the slope of the surface starts from 10 °, but in this case the attic space will not be passable and suitable for living. Therefore, insulation and additional ventilation are not required. The optimal angle of inclination is considered to be 30-50o. On a pitched roof, snow accumulates less, but there is an additional wind load. It makes sense to install a roof aerator only on insulated roofs above residential attic spaces.

Consider what it consists of and what processes take place in the structure. The supporting structure consists of wooden rafters and battens. Insulation, as a rule, is arranged between the rafter legs and is protected from the inside with a vapor barrier film. In the air of any living space there is moisture, the film protects the insulation from getting wet. On the outer side of the insulation under the roofing, a waterproofing film is arranged, which protects the insulation from rain leaks and condensate. Thermal physics of a pitched roof: It would seem that the design is flawless, but not a single film is capable of 100% protecting the roofing pie. As a result, moist air accumulates and stagnates under the roof covering, due to which the wood succumbs to decay and steel corrodes. Installing aerators allows you to deal with this problem, because they organize the circulation of fresh air.

Types and designs

For pitched roofs, a roof aerator is installed in two types:

Point (pitch).
Skate.

They try to install point roofing aerators at the highest points, approximately at the level of 150 mm from the ridge. The outside air is colder, getting into the under-roof space through the eaves, it becomes warmer and tends to rise. The result is an air exchange.

For pitched roofs the following structures apply:

Image	Name	Characteristics
	dotted	Installs at any angle. H=450 mm, D=110 mm. Consumption - 1 pc. for 80 m2.
	dotted	Size - 530×465×110 mm Hole size - 250×160 mm.
	dotted	Length 420 mm. Width 310 mm.
	skating	Size - 610×284×34mm. Protected against insects and atmospheric precipitation.

flat roofs

In flat roofs, the roofing pie is arranged differently. The surface of the floor slabs is leveled with a cement-sand screed. Then the heater is laid. On top of the insulation under the roofing carpet, a leveling cement-sand screed or a screed of two layers of flat asbestos-cement sheets. The surface of the screed is smeared with bituminous mastic or a primer to improve adhesion (adhesion) with the materials being deposited. The built-up roofing mat is firmly bonded to the screed after installation. But during operation, the materials experience temperature changes in the outside air. The coefficient of thermal expansion for concrete, cement, asbestos, bitumen is different, so tension builds up inside the roofing pie. Cohesion, bonds are broken, formed air bubbles. Aerators on the roof are installed under the built-up layers in order to relieve stress and remove air bubbles. Installation of roof aerators on a flat roof:

Types and designs

Aerators for roofs made of built-up bituminous materials do not differ in a special constructive variety. They consist of 3 parts:

Skirts - for stability.
Tubes - for exhaust.
Cap - for protection from atmospheric precipitation.

Some models have pressure rings to protect against leaks. The following types of aerators on the roof are produced:

Image	Characteristics
	Weight - 0.33 kg. Diameter: skirts - 280 mm, tubes - 75÷55 mm, cap - 146 mm. Height - 260 mm.
	Weight - 1.05 kg. Diameter: tubes - 148÷100 mm, cap - 210 mm. Height - 470 mm.
	Weight - 1.23 kg. Diameter: skirts - 390 mm, tubes - 130÷100 mm, cap - 200 mm. Height - 470 mm.
	Weight - 0.43 kg. Diameter: skirts - 280 mm, tubes - 75÷55mm, cap - 146 mm. Height - 360 mm.

All roof aerators are made of high-strength polypropylene and can withstand outdoor air temperature fluctuations from -50°C to +130°C. Consumption - 1 aerator for a roof on an area up to 80-100 m2, but the distance between them is no more than 12 m.

Wind vane installation

As a rule, a roof aerator is installed during the construction and repair of the roof. Installation of a weather vane on the roof is as follows:

The bottom layer of the roofing carpet is welded.
The location where the device will be installed is determined.
A hole equal to the diameter of the tube at the base of the wind vane is hollowed out in the cement-sand screed. The heater is removed from the hole.
The hole in the roof is filled with expanded clay.
The aerator is installed on the roof and fastened with self-tapping screws (or other fasteners) to the screed.
The top layer of the roofing carpet is welded.
You can make an additional layer at the junction of the roofing carpet to the wind vane.

By the way, today many builders and suppliers of materials use the name "wind vane" for aerators. However, they are not exactly the same. Since the time of Peter I in Russia, the design of a weather vane, a device showing the direction of the wind, has appeared from Holland. As a rule, it was installed on a chimney, which is protected from snow and rain by umbrella roofs. Here they are, and there are flyugarki. On the other hand, each aerator also certainly has protection from atmospheric precipitation. We can say that the umbrella-vane is part of the aerator.

Choice and cost

How to choose the right aerator? The design of the aerator depends on the following factors:

from the type of roof;
on the amount of precipitation, including the height of the snow cover;
from the financial possibilities of the owners.

Today, the cost of one aerator is from 300 to 5000 rubles apiece. The price depends on the manufacturer, foreign deliveries, of course, are more expensive. However, it is not worth saving on ventilation, especially since the increased life of the roof will save on its repair in the future.

In order for a long-term and, no less important, safe operation of a soft roof, you need to take care of a competent ventilation device under the roof. The lack of ventilation of the space under the roof is fraught with a lot of troubles - from leaks, the smell of dampness to the very rapid destruction of the roof covering material, which, believe me, is quite expensive. Installing aerators on a soft roof is one of the important elements, but not used by everyone. We want to show the need for its device.

The problem can be solved by installing aerators on a soft roof. The air circulating through these artificial ventilation ducts prevents the accumulation of condensate, respectively, protects the wooden elements from decay, mold formation, dries out the insulation layer of the roofing pie, and more.

Thus, the presence of ventilation aerators for a soft roof protects it from damage, guarantees comfortable accommodation in home.

Why does moisture condense under the roof

Even the presence of vapor barrier and waterproofing in the composition of the roof pie cannot completely block the access of wet vapors, human waste products, from residential premises.

When warm vapor comes into contact with a colder surface, then, as is known from the course of physics, it begins to condense, forming tiny drops of water. They settle on various materials and structures (rafters, insulation, etc.) and impregnate them.

Moisture can get into the roof space and outside. Warm air, accumulated in the attic, warms the roof from the inside, because of which the snow cover on the roof begins to melt in winter. As the temperature drops, frost forms in places. Under appropriate conditions, it also melts. Through the joints of the roofing material, water penetrates inside, and the roof, thus, begins to leak.

The roof covering also suffers. When the temperature drops, the moisture that has penetrated into the formed microcracks can destroy the material. As a result, microcracks become visible, possibly even through.

On a soft roof, the following defects are most common, caused by excess moisture in the drink:

bubbles on the surface. As a rule, the top layer in the pie of such a roof is waterproofing, and the bottom layer is vapor barrier. In fact, they form a closed airtight circuit.
In hot weather, the temperature of the roofing cake can reach as much as 100 °. Under such conditions, the water accumulated in the circuit turns into steam, ready to evaporate. This can cause swelling on the surface or destruction of the roof.
The efficiency of the heater decreases. Wet thermal insulation loses its effectiveness: wetting by two percent increases the thermal conductivity of the insulation by forty percent. As a result, the roof begins to retain heat much worse. Accordingly, the cost of heating increases.
Covers collapse. The structure of cement-sand compositions, from which they are usually made, is capillary-porous. As soon as the temperature drops, the water that gets into these pores crystallizes. Having increased in volume, it presses against the pores with greater force from the inside. As a result, they are destroyed.

What is the essence of roof aeration

Excess moisture from under the roof is removed by evaporation, which is made possible by the movement of air currents. The pressure readings inside the house and outside are very different, so the air will begin to circulate as soon as the two environments are communicated.

Creating effective ventilation for a cold attic is quite simple. Enough to confine dormer window, cracks in the area of \u200b\u200bthe ridge or a loose fit of the overhangs of the eaves.

In the case of a warm attic or attic, such a solution is unacceptable, since in the cold season unregulated ventilation will cause a decrease in the temperature in the premises.

The best option for them are roofing aerators for soft roofs (photo below), through which the spaces under and above the roof are connected. In the passage pipe of the aerator for shingles a forced draft is formed, caused by a pressure difference, which helps to draw wet vapors out.

shingle aerator

In order for the ventilation of the soft roof roof to function normally, an air supply from the outside is necessary. They enter through the ventilation gaps (air vents) provided on the cornices. The air taken in from the street in the process of passing through warm attic heats up, then rushes up - directly to the roof. Draft formed in the aerator on the roof , brings the air flow through the passage pipe and throws it out.

On a note

Ridge aerator for soft roofs correct installation in one hour, it passes the air twice through the eaves on the cornices and the layers of the roofing cake, drying and ventilating it.

Installing aerators on a soft roof in the required quantity ensures dryness of both the roof covering and the insulation. It is noteworthy that the ventilation of the soft roof through the roof aerator will be able to prevent the accumulation of moisture under the new roof, as well as to dry the old cake, which has already been saturated with moisture.

Types of aerators

There are three types of installations working on the ventilation of the under-roof space:

Continuous are mostly mounted on a ridge. The model must be placed along the entire length of the junction of the slopes. Externally, the design looks like a corner element with holes. Open cavities are protected by barriers that prevent precipitation, dust and insects from entering under the roof.

Point aerators located in separate places of the roof, where moisture and steam removal is most needed. Most often these are slopes, less often - a skate. They are installed in a specific order. Each such design is nothing more than a ventilation pipe with a protective cap. Usually the latter has the form of a "box" or "fungus".

On a note

The point pitched structure is connected to the roof by means of a flat base, the ridge structure has an angular base, through which it mates with the roof near the roofing rib.

Turbine - the most powerful: they extract moisture from both the roofing pie and from the premises of the house. To extract moist air, the device is equipped with an electric drive. Models of this type are selected taking into account the slope of the slope. It should also be noted that they are not suitable for installation on slopes with a large angle of inclination.

It is important to note that each type of roof covering requires an aerator made of a specific material. Let's look at a few examples. Let's start with shingles.

The under-roof space aerator in this case is made of polypropylene, which is highly impact-resistant. In addition, it successfully resists temperature extremes, exposure to ultraviolet radiation, and corrosion. As a rule, the joints of the plates or the highest elevation of the slope are chosen as installation sites.

For metal tiles. The aerator is made from metals that are resistant to various aggressive influences, including corrosion. Installed on almost any part of the roof.
For profile. The installations are made of the same material as in the previous case, only it needs to be installed closer to the ridge.

Design features suggest significant differences in the approach to installing aerators on a soft roof.

Installation of aerators on a soft roof step by step

Recall what an aerator is (see photo). This is an artificial ventilation duct that works both to extract moisture out from under the roof and to circulate air.

Consider, separately, how each type of aerator, ridge and point, is mounted.

The device of the ridge version is extremely simple. It is suitable for roofs with an angle of inclination ranging from 12 to 45°.

On both sides of the ridge or on its top, a groove is cut for ventilation with a thickness of 30–80 mm. The choice of a specific thickness is initially determined by the manufacturer. To work with a solid base, use a circular saw.
The slots should end without reaching the edge of the ridge by 300 mm, and not violate the integrity of the slopes on both sides.
On the solid sections remaining along the edges of the ridge, ridge tiles are applied.
Then a ridge aerator is applied. All its segments are fixed on elongated roofing nails or on screws that are screwed through the ready-made holes on the part. The segments themselves are attached similarly to the details of the designer.
On the finished structure lay ridge tiles. The principle of installation differs little from the usual method: the difference is only in the fastening elements. These should be elongated fasteners.
The tightness of the structure ensures silicone sealant, which close up its ends.

The video plot details the nuances of the process of installing aerators on a soft roof.

Scheme of the device for spot ventilation of a soft roof

The mounting scheme for the point version is somewhat more complicated:

As you know, a soft roof is laid on a continuous crate of plywood or OSB. A hole is cut out in it, deepened to the heat-insulating layer. Its diameter must exactly correspond to the dimensions of the internal opening of the channel of the artificial ventilation gap. If the diameter is smaller, then dents will begin to form on the surface of the roof covering, where moisture or dirt will accumulate, if more, then an additional sealing gasket will be needed.

If for any reason the insulation in this place turned out to be too wet, then it must be completely or partially replaced. Thus, it will be possible to maintain the thermal conductivity of the heat insulator at the proper level.

For marking, the skirt is placed on the crate, the contours of the ventilation duct opening are circled with a pencil or a nail, and a hole is cut out along the resulting contour with a jigsaw.
An aerator skirt is placed on top of it, which is fixed with at least 6 roofing nails or screws.

On the recommendation of some manufacturers, in addition to fasteners, additionally used to increase adhesion bituminous mastic. With this approach, sealant is first applied to the back of the tube base and tightly glued to the slope, after which fasteners are used.

A protective frame is put on the skirt and screwed with self-tapping screws. After that, they mount a cap that protects the roof pie from the penetration of precipitation, snap it in and fasten it to self-tapping screws.
The docking point is sealed and an additional layer of waterproofing is necessarily applied.
Similarly, the installation of the remaining point models (according to calculations) is carried out, which form a single ventilation system.
Tiles are laid on top of the skirt, cutting the petals along the junction line.

When installing aerators, the size and shape of the roof, the state of the vapor barrier, and the degree of air humidity are taken into account.
The installation of aerators for a flat roof with a simple configuration is recommended at the rate of 1 fungus / 100 sq. m of roof surface. However, they should be separated from each other by no more than 12 m.
If the roof structure has valleys or a clearly defined ridge, artificial ventilation ducts are located in the watershed areas.
The calculation of ventilated installation systems for buildings with a high level of humidity is best entrusted to construction design companies.
Professionals recommend completing aerating systems from the same supplier. In this way, the risk of problems can be reduced when defective parts are replaced.

The most popular brands of manufacturers of aerators

One of the first models of the family of continuous devices is the ridge. Let's start with him.

Ridge Master Aerators(USA) (Plus and other modification of HipMaster). The shape of the profile design, it is patented) eliminates damage.

Ridge Master models can only be installed on strictly horizontal skates. They are not recommended for use on inclined ribs. For these cases, the Hip Master is suitable. Let's note some advantages of ventilating aerators of this producer.

Special patented system for protection against precipitation and wind. It has a special design of internal partitions, designed on a computer.
The protective frame is soldered by ultrasound.
Built-in interlocking edges allow quick and much more secure joining of structural parts, increase weather resistance, and provide an accurate fit to the slopes.
The aerator successfully resists crushing. It provides support for fasteners, as well as specially designed ribs that keep the roofline even and smooth.
The structure does not form dents, for example, from branches or cracks during sudden changes in temperature, it is resistant to hammer blows.
Manufacturer's warranty - 40 years.

Tokonky aerator for soft roof TechnoNIKOL- completely similar to Ridge Master, but different in length. Ventilation efficiency: approx. 1 element/25 sq.m.

TechnoNIKOL also offers various options point models. Here are some of them.

KTV pitched. Used exclusively for roof coverings their shingles. They are attached to the roof through the passage element in the process of laying soft tiles. The device is difficult to see on the roof. Ventilation efficiency: approx. 1 element / 5-10 sq.m.
KTV alpha. This is an economy version of the pitched model of the KTV aerator for flexible tiles. Protected from weather and insects by a polyurethane (reticulated) filter. Ventilation efficiency: approx. 1 element/20 sq.m.
Pilot pitched. Used on roofs covered with shingles. It is attached to the roof through the passage element directly in the process of laying the roofing material. The lower sliding element allows you to fix it strictly vertically with any roof slope. Ventilation efficiency: approx. 1 element / 5 sq.m.

Finnish manufacturer SK Toute offers wide range of destination aerators. Vilpe Vent models fundamentally different from products from other manufacturers:

The exceptionally high quality of the materials used, which provides excellent characteristics of such systems: exceptional resistance to aggressive environmental influences and ultraviolet radiation.
They are reliably protected from corrosion.
Universal, that is, they can be installed on any roofing system.
High degree of sound insulation.