Ventilation pipes in the roof ridge. Roof ventilation equipment. Pitched roof ventilation

A fairly simple question, how the height of a ventilation pipe above the roof is determined according to SNiP, often confuses even self-confident designers, what can we say about amateur builders who have planned a refurbishment or major reconstruction of their home. The question, meanwhile, is far from idle, since the fundamental characteristic - its performance in terms of the volume of air moved - depends on the height of the ventilation pipe above the roof.

What regulates the height of the ventilation outlet?

The basic law of a vertical pipe, no matter whether it is a ventilation or a chimney, states that the greater the height of the device, the higher the draft in the pipe. Accordingly, the greater amount of air is emitted by the system beyond the roof. Design specialists and most developers, when calculating the height of the ventilation pipe above the roof, are guided by several fundamental documents:

• SNiP No. 41-01-2003, clause 6-6-12, adjustable lift for chimneys;
• SNiP No. 2.04.05-91, defining the design of structures exhaust systems in the old edition;
• SP No. 7.13130.2009 - guidelines and design rules for ventilation and air conditioning systems;
• SNiP No. 2.04.01 determines the level of ventilation output for sewer risers.

In the latter case, the method for determining the installation level of a ventilation pipe according to the provisions of SNiP is described in sufficient detail:

• On flat roof the rise of the exhaust pipe through which sewer gases are discharged must be at least 30 cm;
• For a pitched roof, the height of the stand must be at least 50 cm from the point on the roof to the cut of the pipe;
• On a roof, the surface of which is used for work or movement, the outlet cut of the ventilation system must be located above the roof plane at a level of at least 300 cm.

The outlet of the ventilation system for sewer risers, according to SNiP, must be removed from windows and air intakes at a distance of at least 4 m, everything is quite simple and understandable, because we are talking about gases and fumes that are potentially dangerous to human health.

Approximately the same approach is implemented in SNiP No. 41-01-2003 when setting out the methodology for calculating the height of the chimney pipe above the level of the ridge beam or the horizon of a flat roof.

For your information! The methodology for calculating the height of a ventilation pipe above the roof of a private house is not given in SNiP; only general recommendations are given.

The developers of building codes and regulations No. 41-01-2003 proposed, when determining the excess of a ventilation rack, to be guided by a diagram for calculating chimneys. With one amendment, if the ventilation rack is installed in line with the chimney with a distance of up to 3 m, they must be installed at the same level.

How to determine the necessary and sufficient height of the ventilation pipe

The absence of a separate method for determining the height of the ventilation system pipe does not mean that such a calculation is not required or is not needed. The easiest way is to make ventilation according to a simplified scheme. If you follow the definitions of SNiP No. 41-01-2003, the height ventilation outlet must be:

• On a flat roof - at least 500 mm;
• For a pitched roof, the cut of the ventilation rack should be 500 mm above the ridge line at a distance from the ridge of no more than 1500 mm.

The ventilation outlet can be at the same height as the ridge if the distance does not exceed 3 m, otherwise the cut of the ventilation pipe should not be below a conventional line drawn down to the horizon at an angle of 10 degrees. If there is a chimney nearby stove heating, then the chimney and ventilation pipe must be raised above the cut of the chimney.

To understand how valid this approximation is, you can perform an approximate calculation of the performance of the ventilation duct. For example, a 16 kW/h heating boiler produces about 140 m 3 of combustion products, the flow of fresh air is provided by a chimney outlet channel with a cross-section of 200-220 cm 2.

In order to provide the required 1.5-2 m 3 per hour air change frequency for residential premises of 60 m 2 with a ceiling height of 2 m, the flow rate is 150 m 3, that is, at certain conditions The dimensions and installation height of the chimney and ventilation pipe are approximately comparable. The comparison is quite arbitrary, but it clearly shows that the methods are at least comparable.

What affects ventilation performance

There is another way to determine the height of the pipe and, accordingly, the excess of the roof of the house above the roofing covering. This can be done using the formula for air flow depending on the pressure drop. It is known that when rising by 12 m, air pressure drops by 101 Pa. The result obtained will be valid only for an ideal ventilation system with an absolutely smooth inner surface.

In fact, for practical calculation of the parameters, height and cross-section of the ventilation duct, several important conditions will need to be taken into account:

• Air flow speed at the installation height of the ventilation pipe;
• Air temperature outdoors and indoors;
• Channel cross-sectional shape and surface quality along the entire height of the air duct;
• Roof shape.

By practical measurement, you can obtain the flow coefficient C. From its value and the difference in pressure at the ground and at the installation height of the outlet ventilation rack, you can calculate the actual air flow.

Or vice versa, knowing C and the known air flow rate that will have to move through the air duct for a specific volume of the room, you can determine the pressure difference and, ultimately, the level of rise of the ventilation outlet.

It is quite difficult to make such a calculation, so they usually use the recommendations of reference books on the repair and design of ventilation systems, which provide approximate dependences of the air flow on the outlet pipe extension for various options roof structures and outlets.

Recommendations for determining the height of a ventilation pipe on a roof in no way relate to determining the size of the duct and the draft in the air duct. There is only one reference in the standard, which requires that the total height of the vertical part of the chimney duct be at least 5 m.

The extension of a chimney or ventilation pipe above the roofing is established by SNiP standards for completely different reasons. If you look at the terminal installation diagram recommended by SNiP, it becomes clear that the cut of the ventilation and smoke duct should be at the level of the fastest air flows. The higher the air speed, the stronger the draft, and vice versa - in calm conditions the ventilation system works extremely unsatisfactorily.

Conclusion

If the roof is flat or has a small slope of 5-10 o, then the height of the ventilation system outlet is not important, 400-600 mm is enough. For gable systems with steep slopes, it is necessary to follow the recommendations of the regulations. For multi-level structures with dormer windows and complex broken slopes in addition to following the recommendations normative document, you will have to spend time looking for a place where air flows have the most stable speed. Otherwise, the air will move jerkily in the air ducts, hum and sometimes stop moving, which clearly does not add comfort. In this case, it is necessary to install additional resonators and increase the number of ventilation leads. The performance of six outputs will correspond to two huge racks, and the uniformity of the flow is 2-3 times higher, if, of course, all racks are evenly distributed over the ramp area and not collected in one bunch.

Sergey Novozhilov - roofing materials expert with 9 years of experience practical work in area engineering solutions in construction.

It’s not even worth talking about the need for roof ventilation. Everyone knows this. But this article will discuss how to make it effective, durable, and also install it yourself, using advanced engineering practices.

Why do you need roof ventilation?

The importance of the roof is difficult to overestimate. Therefore, when erecting a building, experienced builders arrange the roof with special care, providing it with reliable insulation, insulation and a ventilation system.

During the operation of the house, steam is generated indoors, which, according to the laws of physics, rises into the under-roof space. And if there is no properly adjusted roof ventilation, then steam settles on the roof structures, rendering them unusable and destroying the load-bearing elements of the building.

A roof without ventilation is dangerous. Increased humidity will lead to the formation of mold and mildew on the walls, wetting of the insulation, and therefore deterioration of thermal conductivity and freezing of the house. A well-established roof ventilation system will help to avoid this, which will remove condensation outside and prevent it from ruining the entire structure.

In order to extend the life of the roof, it is equipped with a high-quality ventilation system

Home ventilation can be spot or continuous, natural or forced. The most common sources of air circulation include:

• dormer windows;
• ridges of pitched roofs;
• gaps provided in the roofing pie and cornice strips;
• exhaust fans on roofs and other piece elements of the ventilation system with holes.

Sufficient for small or medium roofs natural ventilation. Forced ventilation elements are installed on large roofs, where natural air exchange of the under-roof space is insufficient.

Elements of roof ventilation system

The assembly of ventilation components (including labor) is no more than 2–5% of the cost of the roof itself, which is much less than what will be required to repair the roof, individual sections of the house, or even the entire building as a whole, if the ventilation system is not installed or installed on “maybe, I suppose, somehow.”

The main tasks assigned to the elements of the ventilation system:

• removal of steam entering the under-roof space from interior spaces Houses;
• decline heat flow penetrating under the roof due to its heating in the sun;
• equalizing the temperature of the roof to prevent the formation of icicles on the edges of the eaves and ice on the roof surface.

Ventilation roofing tape

The ventilation tape covers all the cracks in the roof, while ensuring sufficient air exchange and protecting the under-roof space from debris, invasion of birds and other small animals.

Depending on the purpose there are:

• ridge ventilation tape;
• perforated cornice tape (overhang aero element).

Advantages of using roofing tape:

• creates good breathability;
• emphasizes decorative finishing roofs;
• Provides protection from moisture, debris and insects.

Ridge roofing tape protects the roof ridge from precipitation and snow getting under the roof. Along with this, it removes steam from the roofing pie, preventing wetting and rotting rafter system and covering material.

Good ventilation tape famous manufacturers, as a rule, is treated with special compounds against UV radiation, which provides additional protection of roof joints from destructive solar radiation.

The ridge ventilation tape is placed under the metal plate of the ridge

Ventilation roofing mesh

For pitched roofs, in addition to proper air exchange, protection from insects is also an important task. Hornets, wasps and small birds populate the under-roof space, build nests, thereby creating not only a noise effect and unsanitary conditions, but also interfering with the natural ventilation of the roof. To combat such a scourge, a ventilation mosquito net with cells measuring 2–3 mm is designed.

Stainless steel mesh is considered the best, as it is the most durable and strong. It is resistant to corrosion, does not spoil the exterior of the house, and has a much longer service life than analogues. The only downside is the high price compared to other types of mesh.

It is undesirable to use steel mesh, as they corrode due to condensation leaks, rot and rust. In order to save money, it is better to use a painting mesh with small cells as a budget option. Its advantage is its low cost and ease of installation - the mesh is laid overlapping and fastened with a stapler to the wooden parts of the roof. However, the painting mesh is not very strong and therefore short-lived.

Roof ventilation passage elements

Passing elements (penetrations) - component ventilation pipes. They are designed to seal roof openings. As a rule, they are not included in the delivery package, but are selected separately for each type of roof.

Penetrations are varied in shape, size, color, which is determined primarily by the manufacturer, and secondly by the roofing covering (soft roofing, corrugated sheeting, metal tiles). But they are all easy to install. They are installed both at the construction stages and already finished roof.

Only with precisely selected passage parts corresponding to the covering material can we talk about the durability of the ventilation system, the absence of leaks in the tie-in areas and the ability of the roofing components to withstand all climatic loads.

Aerator for roof ventilation

Roofing accessories such as aerators are designed for more effective ventilation of soft roofs. These are elements of forced ventilation that reduce pressure under the roof and increase draft, which ensures the necessary air flow.

Aerators are selected depending on the roof area, observing the following rules:

• aerators are installed in the highest places of the slopes along the entire length of the roof for uniform ventilation of the entire under-roof space;
• the distance between adjacent devices is maintained at least 12 m;
• aerators are mounted on dowels or anchor bolts and equipped with filters that prevent the ingress of dirt, moisture and insects;
• to set up the system during roof construction, select areas at the joints of the seal;
• To prevent leaks, use sealant or special tape.

Ventilation accessories also include an overhang ridge, which has a frequent row of teeth that protect the eaves gap and the adjacent under-roof space, as well as roof fans. They are indispensable on flat roofs with insufficient natural convection and on pitched roofs when it is not possible to arrange natural ventilation.

Video: installation of the Systemair DVS roof fan

Ventilation passage through the roof

Any ventilation duct is led to the roof of the house and forms a so-called passage unit (PU) at the exit points in the form of a pipe inserted either into the roof itself through the outlet or into reinforced concrete glasses.

Industrial ventilation passage units are manufactured in accordance with GOST 15150 and are:

Depending on the type of roofing and design features roofs and air vents, they differ in shape:

Along with typical elements, non-standard assemblies are often manufactured, designed to be original in structure and assembly ventilation systems. However, all of them must meet the requirements defined by GOST:

• metal thickness for manufacturing is at least 11.9 mm;
• the size of the support ring is 30–40 cm larger than the diameter of the pipe;
• mandatory treatment with anti-corrosion compounds;
• the length of the unit design without valve is no more than 1 m.

The passage units for chimney ducts are arranged in strict compliance with fire safety regulations.

Ventilation gap on the roof

Many people wonder whether a ventilation gap is needed and, if so, why. Is it possible not to do it, since there is already a gap between the covering and the sheathing.

But is it really necessary to have a ventilation gap on the roof? Let's try to figure it out. Ventilation of the under-roof room consists of three gaps: the eaves, through which air flows, the gap between the roof and the insulation (the membrane does not count) and the gap at the highest point of the roof (ridge or abutment).

Their goal is to ensure good air circulation under the roof and prevent the insulation from getting wet. And if you neglect the gap on the roof, the consequences will be very disastrous - you will have to disassemble roofing pie and change the insulation. And this is the least of all troubles.

Additionally, hard surfaces typically require repainting every 10 to 20 years. But if there is no gap, the resulting condensation will spoil the flooring sheets from the inside. And while painting them on top is quite simple, it is impossible to do this from the inside without dismantling the entire roofing pie and replacing the sheets completely.

So the answer to all questions is obvious - make gaps. Allow the roof to breathe to avoid problems that are initially unnoticeable but snowball. In addition, the gap on the roof must be sufficient to ensure the operation of the entire chain.

If you block the roof ridge, that is, do not create a gap, there will be no benefit from the gap between the insulation and the roof, as well as the eaves clearance.

Metal roof ventilation

Metal roof beautiful, modern, durable and reliable, but it has one big drawback - limited air exchange, i.e. it does not allow air to pass through well. To ensure normal circulation, ventilation is installed according to the following algorithm:

Video: ventilation of the under-roof space in metal roofs

Ventilation of soft tile roofs

Ventilation of a soft roof faces the following tasks:

• removal of condensate;
• preventing overheating of the lower layers roofing;
• ensuring temperature balance on the roof surface.

With properly organized ventilation, cold air flows enter the under-roof space at the overhangs and exit through the ridge or aerators.

Ventilation of soft roofs can be single- or double-circuit. But for it to be sufficient, a number of conditions must be met:

• the thickness of the air gap between the sheathing and the insulation is calculated in advance based on the angle of inclination and the length of the slopes (but less than 4 cm);
• make additional holes along the bottom of the slope, tightening them with perforated tape, mesh, comb, lining the roof overhangs with breathable soffits;
• arrange gaps on the roof in the form of ventilated ridges or aerators for forced ventilation.

If the roof is not new, and the soft roof is being repaired, then look for places with the greatest swelling, and install aerators there.

Video: ventilation of the under-roof space in roofs made of flexible bitumen tiles

Hip roof ventilation

Ventilation hip roofs can be roughly divided into two groups - ventilation of a cold attic and an insulated attic.

Arranging ventilation for a cold attic space will not present any difficulties. Due to the large volume of the attic, there are practically no barriers to normal air circulation. Air exchange occurs through the eaves overhang, ridge and ridge. Dormer windows, covered with gratings and located on opposite sides of the roof, provide a draft.

When it is necessary to increase ventilation, aerators are installed along the passage of the valleys. But they make sense if the slope angle is more than 45°. Otherwise, in difficult areas in winter time Due to the accumulation of snow, the operation of aerators will be ineffective.

For small slopes, it is better to do forced ventilation using roof fans, inertial turbines or nozzles of sufficient height so that they are not covered with snow.

Video: how to eliminate condensation in the attic

Ventilation of insulated under-roof space (attic)

It is advisable to plan the ventilation of the attic during construction, since its arrangement is more labor-intensive than the ventilation equipment for a cold attic space. There is no free air circulation here, which is why the space for air exchange is created by the sheathing installed between the insulation and the flooring.

In addition, a gap of at least 2–3 cm between the hydro- and thermal insulation is required. If the depth of the rafters does not allow for the required gap, then they are built up using boards.

But this method of air exchange is quite difficult to implement on roofs of complex shapes with many kinks and junctions. Therefore, roofers advise installing diffusion membranes (vapor-permeable) directly on the insulation, which allow moisture to pass through only in one direction.

Video: ventilated ridge on an attic roof

Seam roof ventilation

A seam roof, like all other types of roofs, requires normal air circulation in the under-roof space. And this is ensured by a gap between the coating and the heat-insulating layer of at least 50 mm, for which a sheathing of 50x40 or 50x50 mm timber is assembled. In addition, for greater reliability, the insulation is protected with a vapor barrier film.

To remove moisture from the ventilation gap on the roof, install a ventilation outlet for a seam roof at a distance from the ridge of no more than 0.6 m.

A seam roof laid according to all the rules and well ventilated will last about 25 years without overhaul.

Pitched roof ventilation

To equip the ventilation of pitched roofs you need:

• inlet gaps in the lower roof area;
• channels for air circulation above the insulation (due to the sheathing);
• hoods at the top of the roof have an area of ​​15% larger than the area of ​​the supply openings, since good ventilation requires reduced pressure in the attic.

It is not difficult to arrange ventilation with your own hands. General scheme one is to provide gaps under the eaves overhangs, protect them with tape or mesh, and create a gap between the sheathing and the insulation.

Further work depends on the roof slope. When the slopes have a slope of 10–45°, the exhaust gap is located in the ridge and is covered ridge aerator with protective filter made of polyurethane foam. One such aerator, about 60 cm long, ventilates 25 m² of attic space.

Video: installing a ridge aerator

If the structure of the roof does not provide for a ridge or the slope of the slopes is from 5 to 12°, then it is necessary to increase the number of supply holes at the bottom of the roof, and install aerators in the upper zone at a distance of 0.5–0.8 m from the highest point of the roof.

With this arrangement, the aerator ventilates 5 m² of the attic space, but if the building is located in a well-ventilated area, then it throughput increases to 25 m².

Video: installation of a point aerator

Ridge vent size

The size of the ventilated gap depends on the slope of the slopes - the lower the roof slope, the greater the height of the gap. The type of thermal insulation material does not affect the size of the gap, but the type of roofing is very important. Under a hard covering (metal tiles, corrugated sheeting), you can use a counter lath for lathing a small section of 25x50 mm, since this is not a continuous covering, but has its own gaps and joints, through which air also circulates. Although experts do not advise experimenting and, for greater reliability and durability, they recommend using 50x50 mm bars for all coatings, i.e., making the optimal gap height 50 mm.

How to remove a pipe through a roof made of corrugated sheets

Any home heating system, with the exception of an electric one, requires chimneys to be vented onto the roof to release combustion products into the atmosphere. Let's look at how to remove a chimney through corrugated sheeting.

1. First you need to make sure correct location chimney pipe - the exit point should be in the darkened northern side, where little sun reaches.
2. The shape of the pipe and the size of its cross-section are selected, taking into account the climatic conditions of the area, the topography and the temperature of the outlet gases.
3. Then they are determined with the height of the pipe according to SNiP.
4. They make the pipe themselves, or buy a ready-made one and install it.

Video: pipe passage through a corrugated roof

Height of ventilation shafts according to SNiP

When calculating the height of ventilation shafts, take into account:

• the elevation of the pipe relative to the highest point of the roof and adjacent buildings;
• total length of the smoke channel;
• head size;
• design height.

Requirements and standards according to SNiP:

If there are outlets of other ventilation ducts nearby, the height should exceed the others by 20 cm.

Video: how to calculate the height of the chimney

Ventilation aerators are special devices for ventilating the under-roof space and removing moisture and water vapor to the outside. Used on flat roofs, preventing swelling of the covering roll material due to temperature changes, and on pitched roofs for effective ventilation and removal of condensate.

Vanes (aerators) are produced in different sizes and designs. They are considered the most effective elements of ventilation systems. On a flat roof, they are installed evenly over the entire surface at the joints of the slabs. On pitched structures placed closer to the ridge (0.6 m from it) or in places where valleys pass (on complex roofs).

The manufacturing material is AISI 316 stainless steel or durable polypropylene, thanks to which they can withstand a wide temperature range from -40 to + 90 °C.

Installation of aerators on a flat roof

When covering with two layers of rolled materials, aerators are installed in the bottom layer:

1. A hole along the diameter of the aerator tube is cut through the screed and layers of insulation.
2. Cover with gravel and attach the aerator to hot mastic.
3. After cooling, fix with self-tapping screws.
4. The top layer of the roofing is fused in such a way that the aerator is at the point of overlap (15 cm) of the sheets, and the junction points are sealed.

Video: DIY aerator installation on a two-layer soft roof, part 1

In single-layer flooring, aerators are installed on the screed, making a hole up to the vapor barrier. The coating is laid on the skirt of the aerator, hot mastic and a patch are applied on top, covering the skirt and extending about 15 cm onto the coating. The aerator is then secured with self-tapping screws, and the joint is treated with sealant.

Video: installation of an aerator on a two-layer soft roof, part 2

Installation of aerators on metal tiles and corrugated sheets

The installation of ventilation outlets on roofs made of metal tiles and corrugated sheets is the same and is associated with damage to the roofing covering, so it must be carried out especially carefully so as not to have to change damaged sheets of covering material.

1. Apply the template (included in the kit) to the installation site, outline and carefully cut a hole along the intended line.
2. The seal is secured with screws and sealant is applied.
3. Install the aerator, secure it with hinges and additional screws.
4. From inside the attic, the passages of ventilation pipes are puttied with sealant.

When installing ventilation elements, you must use proprietary fasteners, which are included in the kit.

Video: installation of ventilation on metal tiles

Main mistakes in installing a ventilation system: how to avoid them

Considering that today many people install the roof of their home on their own, let’s look at the most common mistakes when installing ventilation systems.

1. SNiP standards are not taken into account.
2. Unsuitable ventilation elements selected.
3. The ventilation ducts are not located symmetrically.
4. The system throughput was incorrectly calculated and the heat balance was not taken into account.
5. Installation work was carried out incorrectly.

The basic rule when designing ventilation systems is that the more proportional and shorter the ventilation is, the more efficiently and with less noise it will work.

Overview of ventilation systems

When setting up ventilation, sometimes it becomes difficult to select components. Let's look at the most popular manufacturers whose products deserve attention.

Roof ventilation "Virplast"

WirPlast equipment is used for various purposes - installation of ventilation of rooms or fan exits ( sewer system), as a kitchen hood, for installing antennas or constituent elements solar panels.

Advantages:

• easy installation due to the built-in spirit level, which eliminates any errors;
• complete tightness on the roof;
• stylish design;
• a variety of models for all types of coverage;
• 10 year warranty.

Roof ventilation "TechnoNIKOL"

TechnoNIKOL ventilation systems are available in two variations:

• for ventilation of the under-roof space;
• for forced air circulation in attics and attics.

Advantages:

• aesthetic design and affordable price;
• increased reliability and impact resistance of all elements. Achieved thanks to additives introduced into the composition of the base material HDPE;
• easy installation with detailed instructions.

Roof ventilation Vilpe

Vilpe products are developed by the Finnish company SK Tuote Oy. Excellent as forced ventilation systems installed both during the construction stages and during renovation.

Advantages:

• made of impact-resistant polypropylene and therefore not subject to corrosion;
• resistant to ultraviolet radiation and climatic changes;
• environmentally friendly material, withstands constant temperature changes from -40 to + 80 °C and occasional surges from -55 to +120 °C;
• Wide variety of colors and modern design.

Roof ventilation Kronoplast

The success and demand for Kronoplast products is due to the fact that the company produces almost all parts for the ventilation of a private home - under-roof ventilation, kitchen outlets, vacuum cleaner outlets, sewer risers, etc.

The main feature of this product is 100% impermeability of all exits on the roof, without which full ventilation is impossible. Roofing elements Available for any coating in six basic colors.

Video: installation of ventilation on an ondulin roof

Installation of roof ventilation is an important and necessary process that requires attention and responsibility. It is not difficult to do it yourself, observing the mandatory rules and regulations. Only in this case the roof of the house will never “cry”. Good luck to you.

Despite the hype around some roofing materials, the comfort and warmth in the house is influenced not so much by them as by competent installation of the roof. If the construction was carried out professionally, observing existing standards, then any coating will be a reliable barrier to nature’s surprises, be it cheap slate or expensive metal tiles, and the entire roofing structure will save heat in the house and eliminate excess moisture. But the presence of condensation and high humidity “hints” that not everything is going smoothly with your roof. Well, to be more specific: during installation, the roof ventilation was created incorrectly (if it was created at all!).

And there are several reasons: either the roof was laid by non-professionals, or vapor barrier or waterproofing films were applied incorrectly, or the ventilation system was created without taking into account the type of roofing. There is only one result: you will have to disassemble the roofing pie and reinstall it.

What layers should a roof ventilation system be made of?

Roof ventilation consists of three components, each with its own function:

1. Ventilation between the roofing and the waterproofing layer. Its task is to remove condensation from the roof that forms on the back side of the coating.
2. Ventilation between waterproofing and insulation. It is needed so that moisture that has entered the insulation from the air has the opportunity to leave the roof. If this layer is not created, the insulation can absorb water as a result of roof leaks or during the rainy season and cease to function as a heat insulator.
3. Ventilation of the internal under-roof space. This layer is responsible for removing vapors from the premises and preventing them from settling as condensation on the inside of the roof.

In this roof, the ventilation of the under-roof space is not thought out, so there is a lot of condensation on the roof

What laws of physics should be taken into account when installing ventilation?

Steam and water will seep into the roofing pie from both sides. The ventilation system should either prevent this from happening, or, if it gets in, allow the moisture to evaporate. It should be remembered: the steam does not flow perpendicularly upward, but slightly deviating to the side. The water does not go perpendicularly down, but also deviates slightly.

This deviation is not always taken into account when forming a roofing pie, and the following installation errors are made:

Ventilation of the under-roof space. Errors in ventilation installation will lead to destruction roofing structure

Mistakes in using vapor barrier and waterproofing films

Even if all the necessary air gaps are created in the roofing pie, ventilation will not be able to ventilate all the moisture if the waterproofing or vapor barrier films were installed incorrectly. They are often confused due to their external similarity. But these films have different tasks, and, accordingly, a completely different structure.

Let's consider what problems will fall on the head of the owner who has mixed up the purpose insulating materials:

1. If you laid a vapor barrier film instead of a waterproofing film. The vapor barrier film completely eliminates the ingress of moisture from both sides. If you lay it on top of the insulation, then the moisture that gets from the air into the heat-insulating material (and it will definitely get in, especially during seasons of high humidity!) will remain in it, because it will not find a way out. As a result, every year the insulation will become more and more moistened until it finally loses its properties completely, and the owners will be faced with high heat losses.
2. If you laid a waterproofing film instead of a vapor barrier. Waterproofing films (also called diffusion membranes) have special properties: one side “breathes”, and the other is waterproof. They are laid under the roofing, turning the breathable side towards the heat-insulating layer. In this case, there should be a ventilation vent between the layers. Then the moisture from the insulation will partially escape through the air gap, and the rest will seep through the funnel-shaped holes of the film under the roof and evaporate. If water accidentally gets through the roofing (as a result of leaks, through cracks, etc.), it will settle on the film and will not be able to penetrate deeper. And in the same way as moisture from the insulation, it will go home.

If secured correctly waterproofing material on a skate, then the steam will not find a way out

When installing a waterproofing film, it is the other way around, i.e. on the “breathing side” of the insulation, water and moisture entering from the outside will easily enter the insulation through the funnels, and will no longer be able to get out. As a result, the entire design of the roofing pie loses its meaning.

Another option is when instead vapor barrier film lay waterproofing. If you place it with funnels inside the house, then all the steam will instantly seep into the insulation, if on the contrary, then the moisture from the insulation will return back into the under-roof space, although not much.

Errors in a ventilation system created without taking into account roofing material

Some owners, out of ignorance, create not as many ventilation layers in the pie as a certain roofing requires. For example, metal tiles and euro slate are afraid of condensation on the back side, so a ventilation gap must be provided between them and the waterproofing layer. Those. They fill not a solid sheathing, but a lumber one, leaving gaps for air to circulate. If water gets under the roof from the outside, then with the help of this layer of ventilation it will be able to evaporate through the ridge.

The grille paired with the counter-lattice will create an air gap sufficient for condensation to find its way out

At the same time, anti-condensation films are used as waterproofing, which do not release vapors from the insulation under the roof, thereby relieving the roofing of additional condensation. But here is the second point: where will the moisture go from the heat-insulating material if it is not released under the roof? To do this, create a second layer of ventilation, leaving an air “cushion” between the insulation and the anti-condensation film.

You cannot lay diffusion and superdiffusion membranes as waterproofing, because they are designed to allow steam to pass under the roof, and in such roofs this can lead to corrosion of the metal tiles.

Only a properly created ventilated roof will retain heat and remove excess moisture from the house.

In the roof pie, the waterproofing material is surrounded by a double ventilation gap

Soft tile roofs

And these roofs are not afraid of condensation, so they do not require a serious air gap between the coating and the waterproofing. A continuous sheathing of plywood, boards, etc. is installed under them. Wooden materials themselves allow air to pass through well, so natural ventilation will work in any case.

Creating an air gap between the waterproofing and insulation will depend on which film you choose:

• Anti-condensation films are not installed on soft roofs. Diffusion membranes are used here. But to prevent the funnels from becoming clogged with insulation particles, an air gap must be left.
• If you plan to lay a superdiffusion membrane, then it does not need an air gap. The level of moisture passage is high and allows you to do without a ventilation layer. Such a membrane is laid directly on the heat-insulating material.

In this cake, the waterproofing layer is created using a superdiffusion membrane. It does not require a ventilation gap, but lies directly on the insulation

Having created all the necessary ventilation gaps, it should be remembered that steam will tend upward and water downward only when there is air movement. Don’t forget to make a ventilated underlayment and install aerators on the upper edge of the roof or on the ridge. Otherwise, the roof will not be properly ventilated.

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

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

1. Reliably seals the ridge connection of pitched roofs so that leaks do not occur through it. The triangular shape of the ridge complicates the sealing of this weak spot of the roof made of corrugated sheets and corrugated sheets, through which melt and rain water can leak.
2. Allows access to air. The ventilation gap that is formed when installing a ridge of this design opens the way for heated air inside the room to the street, which creates a kind of draft and forces the air to circulate inside the house.
3. Closes the ventilation gap from the penetration of insects and snow sweeping. The design of the skate is designed in such a way that water cannot flow into it, snow or insects cannot fly into it.
4. Allows excess moisture to evaporate. Vapors saturated with moisture are a product of human activity. They, together with the air, rise upward, cool and condense on the elements of the rafter frame. The thermal insulation layer of a roof made of corrugated sheets, soft tiles or metal tiles loses most of its heat-saving properties when wet, and the wood of the frame rots and becomes moldy. Installing a ventilated ridge solves this problem by opening the air to oxygen and allowing excess moisture to evaporate.

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

Installation of a ventilated ridge does not spoil appearance roof, with high-quality installation this element of the ventilation system cannot be seen. To make the installation site look more aesthetically pleasing, a strip of soft tiles or a metal profile is fixed on top of it, which protects the aerator from exposure to sunlight and the penetration of atmospheric moisture.

Operating principle

In the old days, builders did not even think about installing a ventilated ridge, since air naturally circulated through cracks or gaps in building materials and designs. or corrugated sheeting requires almost complete tightness; installation is carried out in the form of a kind of “pie”, in which there is a layer of insulation, waterproofing and vapor barrier.

• This design does not leave a single chink for air, which is why a stuffy, humid microclimate is established inside the house. To solve this problem, it is necessary to develop high-quality ventilation at the project approval stage. Depending on the type of roof, there are 2 options for ventilation systems: Natural. Natural ventilation is equipped for houses with “cold” roofs in which the attic is not heated. With this design, dormer windows are made in the roof slope, necessary for air circulation. In this case, the unheated attic acts as an “air cushion”, isolating heated rooms from cold roof
• . Installing a ridge with ventilation holes is extremely rare under such circumstances. roll materials equipped with a ridge aerator, as well as eaves vents to force air masses to circulate between the room and the atmosphere. The air flow penetrates the roof structure through the vents, heats up and rises to the ceiling, exiting through the ventilated ridge and making room for fresh air.

Important! Forced ventilation was developed based on the physical properties of gas. Its operation does not require power sources, since the draft is created according to the law of convection: warm air rises up and cold air falls down. To achieve maximum efficiency of the ventilation system, its elements are placed evenly over the entire area of ​​the roof made of corrugated sheets, metal tiles or rolled materials.

Types of aerators

The design of the ventilation system depends on the area of ​​the slopes, the nature of the use of the under-roof space and the type of roofing material. Installation of ventilation for “warm” mansard roofs more difficult and more expensive than for cold ones. To determine the optimal composition and relative position of the elements, installation is performed based on determining the volume of air in the attic. The following types of aerators are used to equip a ventilated ridge:

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

Functions

To a non-professional craftsman, ridge ventilation may seem like an unnecessary extravagance and additional cost, but experienced roofers know that this simple measure increases the life of the rafter frame and roof covering.

1. A properly designed and installed ventilation system performs the following tasks: Optimizes the microclimate in residential premises
2. . Thanks to the constant flow of air saturated with oxygen, the house is always fresh, not stuffy, and a comfortable temperature is maintained.
3. Maintains the healthy condition of the rafter frame and sheathing. Thanks to the aerator, excess moisture evaporates, and the wood of the roof frame does not suffer from rot, mold and mildew.
4. Does not allow the insulation to get wet. Due to constant air circulation, the insulation is ventilated and remains dry, which maintains the thermal insulation qualities of the material at a high level.
5. Makes the use of bitumen-based materials safer. Air circulation through aerators eliminates the possibility of penetration of bitumen vapors, which are considered harmful to human health, indoors.

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

Video instruction

When constructing private buildings with a small number of storeys, it is important to draw up a design of all engineering systems and components that ensure the functionality and durability of the object. It is imperative to consider where the ventilation outlet to the roof will be located, since without this component the building will not meet regulated sanitary and hygienic requirements.

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general information

If you plan to build a turnkey private house or cottage from scratch, you need to determine the optimal place where you can install a ventilation outlet. This type of natural ventilation does not require the purchase of expensive devices and systems, and there will always be a comfortable microclimate inside the room, enriched with fresh air.

In addition, you can equip the structure with a small fan operating on the principle forced exhaust. But if you correctly install the fungus on the roof structure, then you simply won’t have to buy additional devices.

The effectiveness of natural ventilation directly depends on the location of the pipe. Accordingly, the higher the unit is installed, the stronger the thrust in it.

Very often, designers do not draft the installation of risers well enough and select the height above the roof structure. In this regard, various problems may arise in the future. Among them:



If the ventilation pipe is installed incorrectly on the roof structure, the rafters and sheathing may be deformed. Moreover, there will be gaps where the shaft cover is installed, which will increase the risk of rainwater entering the room. Therefore, in order to avoid such consequences and keep the roof in good condition, it is necessary to responsibly approach the issues of arranging ventilation outlets to the roof.

Installation of a ventilation duct in a private house, calculation of the cross-section, diameter and height of the ventilation ducts above the roof



Drafting

You need to begin work on installing a fungus for ventilation on the roof with a preliminary drawing up of the project. It is important to carefully consider the fundamentals of the entire construction, and only after that begin installing the components.

If there is a need to replace the roof as part of the reconstruction, and through the roofing structure it is necessary to remove hoods from all parts of the house, then many may have a question : Is it possible to combine all channels into one? and not separate them into four separate passes?

But experienced experts They argue that this approach will not do anything good, so it is much more reasonable to arrange a separate ventilation passage for each of the air vents. In this case, the problem is with unpleasant smell in living rooms it will simply disappear when weather conditions change.



Purpose and main types

When arranging an exit, you should know about the main subtleties of the upcoming work, understand the types of structures and their purpose. Roof penetrations can be used in different types ventilation systems:

1. 1. In interior rooms cottage
2. 2. B fan pipe sewer riser.
3. 3. In the attic.

Moreover, sometimes these passages are necessary for laying smoke shafts and television antennas. At the end of the air exhaust system there is a special ventilation outlet, which is equipped taking into account all the requirements for the system.

The purpose of such a design is to ensure effective exhaust of air from the room and prevent any leaks. At those points where it is necessary to make a ventilation passage through the roof, special passage elements are placed that correspond to the specific roofing material.

Currently, it is possible to buy ready-made sets of ventilation outlets for their further installation on roofing structures made of hard and soft materials. Such products allow you to quickly and efficiently build a ventilation riser to protect the roof from possible leaks, as well as maintain its aesthetic appeal. Moreover, such devices are a natural protection of ventilation ducts from the penetration of various dirt and precipitation.

The height and shape of the passages through the roof are determined by the individual characteristics of the roof structure. In addition to pipes with a round cross-section, rectangular structures are used.

To ensure that the ventilation pipe does not lead to a violation of the roof’s tightness, it is necessary to follow a certain sequence of actions and take into account the established requirements.



Node device

If we consider the simplest ventilation outlets on the roof, they are a small metal pipe, which is located in a pre-made hole and fixed with fasteners. The roof penetration itself can be equipped with a locking valve and a ring that collects condensate.

At the bottom of the pipe, an outlet channel is connected using a flange, and on top there is a deflector or a regular protective umbrella. You can also consider an option with insulation, which uses mineral wool.

On modern market More advanced types of roof ventilation systems are offered that meet a new level of quality. At the same time, in terms of design features and operating principles, they practically do not differ from traditional solutions, but have a lot of advantages.

Ventilation. Roof outlets and aerators.

Lids from the manufacturer “Vlipe Vent” are in particular demand. The list of advantages of such products includes the following points:



In some circumstances, when the passage element is not included in the kit and is purchased as an additional unit, the type and profile of the roofing covering must be carefully assessed in order to select the optimal unit. A high-quality passage element will become the best solution to ensure design versatility on any type of roof. Such products guarantee maximum stability and tightness of the ventilation outlet.

INSTALLING AN AERATOR FOR ROOF VENTILATION

The task of aerators

It is no secret that during the cold season there is a possibility of condensation forming inside the roof structure. To prevent the penetration of dampness into the room, to avoid the formation of fungal manifestations and mold, it is necessary to properly arrange internal ventilation under the roof.

The roof ventilation device looks very simple: air masses should naturally move in the direction from bottom to top. To supply new portions of fresh air, special openings in the eaves are used, while the flows exit the room through aerators with a lid. They are located in the roof directly at the ridge.

To prevent precipitation from penetrating under the roofing pie, it is necessary to find suitable type pipe covers. The best option is a ventilation fungus on the roof, which performs not only a practical function, but also a decorative one. There are a lot of varieties of such structures on the market, so choosing a beautiful and effective fungus for roof ventilation is not difficult.

Guest house, ventilation

Optimal location

Professional builders recommend placing the pipe directly above the riser. In this case, the productivity of the system will be maximum, which is due to the absence of bending of the channel. If it is not possible to make such an installation, for the correct connection of the nodes it will be necessary to use special corrugated adapters.

On pitched roof made of metal tiles, it is better to install the penetration near the ridge itself. So the long part of the pipe will be under the roof, insulated from external influences. The remaining short element will be able to withstand any wind blows and other processes.

At the installation stage, it is also important to consider the height of the shaft above the roof. An indicator that is too small will negatively affect traction, and one that is too high will be exposed to gusts of wind and quickly deform. In addition, it will have to be additionally secured with guy wires and other fasteners.




According to current construction standards, the optimal height of the shaft above the sloping roof should be no more than 50 centimeters. If the roof is flat, the height indicator is 30 centimeters. When using the roof to create open areas for recreation, the ventilation outlet must rise at least 2 meters.

House ventilation, roof ventilation. VILPE ​​ventilation solutions. how to make ventilation in the house

By following the above guidelines, you can perform high-quality, reliable and durable installation of the ventilation outlet. In this design, it will serve the owner of the premises for a long period of time.

Based on the above, there are practically no difficulties in installing a ventilation duct on the roof. If you draw up the correct project in advance, carry out calculations and study the installation instructions, the future ventilation system will work the best way. At the same time, the service life of the roof, which has gone through a lot of changes due to the appearance of a new unit, will not be reduced in any way. But for this you need to take the upcoming work responsibly and follow the basic installation rules.