Selection and installation of waterproofing for metal tiles: an overview of the types of waterproofing and why do you need a hydro-barrier under the roof? Waterproofing for metal tiles: selection and installation How to make waterproofing for metal tiles.

In private housing construction, roofs made of metal tiles are considered the most practical solution, while they have a rather attractive appearance... But, any experienced roofer will confirm that without performing high-quality waterproofing, the roofing structure will not last long, that is, it is significantly reduced operational period.

Precipitation has a negative impact on the roofing material, insulation, and other structural elements, therefore, the arrangement of waterproofing the roof under the metal tile is a mandatory stage when installing the roof.

In this article

Consequences without the use of waterproofing

Consequences that can be in the case of installation of a metal roof without the use of a waterproofing layer.

• The rafter frame can become damp. When condensation enters the rafters made of wood, which absorbs moisture well, they accordingly begin to become covered with fungus, mold, rot and break down faster. As a result, the deformation of the entire roofing structure is gradually observed.
• Moisture can get on the insulation layer... Insulation that is not protected from moisture by a waterproofing film will dampen, accordingly, its thermal insulation capacity will significantly decrease. It should also be borne in mind that even after complete drying, the thermal insulation characteristics of the insulation material are not restored.
• Corrosionmetal tiles... In the absence of a waterproofing layer, condensation will collect on the inside of the roofing material, resulting in metal surface will begin to rust. The joints are most exposed to corrosion. roofing with a rafter system. As a result of corrosion of metal tiles, the reliability, the service life of the roof is significantly reduced.

Important! Waterproofing the roof of a house for metal tiles is an obligatory stage in the installation of the roof, which guarantees the reliability of the operation of the roofing structure and doubles its operational period.

Basic requirements for waterproofing a metal roof

Waterproofing made of anti-condensation membrane film must meet the following characteristics:

• Reliability, endurance.
• Resistance to mechanical, chemical influences, influences natural environment.
• Maintaining its original shape - resistance to deformation.
• Have a good indicator of hydrophobicity, vapor barrier.
• Avoid the accumulation of condensation.
• High quality workmanship, compliance with established building standards.
• The duration of the operational period.
• Resistance to ultraviolet radiation, temperature extremes, environmental influences (precipitation).

Important! Roof waterproofing for metal tiles must be equipped at a high-quality level, with maximum reliability for the entire roofing structure, otherwise its premature failure cannot be avoided.

A variety of waterproofing substrates

When arranging the waterproofing of the roof of a house, it is necessary to take into account the possibility of condensation forming both under the roofing and under the insulation material. Therefore, with inside waterproofing film an anti-condensation layer is performed, a ventilation gap must be left.

The formation of condensation depends primarily on the installed roof, which can be of a cold, warm type. That is, the intensity of formation, the volume of condensate completely depends on the temperature from below and from above the substrate.

Types of waterproofing films

• Classic. Using of this type ventilation films are arranged in two sections: insulation - waterproofing - roof covering.
• Anti-condensation. A fleecy moisture-absorbing layer is used as a base, double-circuit ventilation is arranged.
• Diffusion membrane. This material is characterized by increased vapor permeability, therefore, ventilation is arranged only between the roof covering and the waterproofing layer.

Waterproofing underlays can also differ depending on the type of roof. It is necessary to consider whether the roofing cake will be heated or not.

Heated roof underlay

If the arrangement of a heated roof is provided, for example, when a living room is equipped in the attic, the device roofing cake has a rather complex design, it is performed step by step.

How to waterproof a roof for metal tiles?

The sequence of arranging the roofing cake for warm roof from metal tiles:

• Lathing, counter-lathing.
• Waterproofing underlay... Provides protection of the roof structure from condensation, water vapor escape from the warm attic room. That is, the waterproofing material must additionally have vapor barrier properties.
• Air gap... The ventilation layer of 2-3 cm ensures that the waterproofing film performs its own functions.
• Thermal insulation... Installation of heat-insulating material is carried out in the rafter system, it is designed to retain heat in the attic. The thickness of the thermal insulation layer is selected depending on the characteristic temperature regime region in which the house is located.
• Vapor barrier... Prevents condensation from entering the living area into the roof space.
• Internal lining of the ceiling of the attic- this is the extreme stage of arranging the roofing pie on the roof.

If, when arranging the roof, you follow all of the above points, then it will reliably serve for a long time, attic room will be warm, comfortable to stay.

Unheated roof underlay

Do you need waterproofing under the cold roof metal tiles?

A more simplified scheme is used for the device of a roofing cake for an unheated roof:

• Lathing, counter-lathing.
• Waterproofing.
• Rafter system.

Accordingly, the installation is much faster.

As waterproofing material any film can protrude: diffusion, anti-condensation membrane, other waterproofing material that does not allow moisture to pass through.

Roofing material for waterproofing underlay

Roofing material is a building material consisting of fiberglass (cardboard) coated with bitumen. The guaranteed service life for roofing material, depending on the operating conditions, can be from 5 to 15 years. If this material use for a waterproofing substrate, then its service life will be longer, since it is limited from direct contact with sunlight.

Important! Roofing material can be used for arranging a waterproofing substrate only if the roof slope is no more than 25º.

Disadvantages of using roofing material

• The base of the roofing material, made of cardboard, quickly resists. Therefore, it is better to use fiberglass-based roofing material, but this material is also short-lived.
• Violation of the integrity of the bituminous coating as a result of exposure to moisture.
• Roofing material from the category of fire hazardous materials.

Important!Roofing material for waterproofing can only be used for arranging a cold roof structure.

Waterproofing laying technology

The main function of the waterproofing material is to protect the wooden truss system, insulation material from moisture and condensation.

The arrangement of the waterproofing layer is carried out after the installation of the rafter frame, but before laying the roofing material.

Waterproofing is performed according to the following scheme:

• The waterproofing film is cut into strips, the length of which should be 10-15% longer than the length of the roof slope.
• Waterproofing of a roof made of metal tiles is carried out with sagging to prevent rupture of the waterproofing material as a result of possible leaks.
• The waterproofing material is attached along the rafters, for which a mounting stapler with stainless steel staples is used.
• Roofing material is attached to the rafters with galvanized nails.
• The joints between the strips of waterproofing material are treated with a special sealant that is resistant to moisture (mounting tape can be used).
• After installing the waterproofing material along the rafters, a counter-lattice of slats is arranged to ensure ventilation.

It is important to remember the basic rule! Without high-quality waterproofing, the operating period for metal roofing is significantly reduced. A waterproofing coating will not only help extend the life of the roof, but also save cash for the premature completion of its repair.

Regarding the question, is it necessary or not to lay waterproofing under the metal tile, experts give only an affirmative answer. This categoricality is explained by the fact that during the operation of roofing decking made of this material from the side facing the inside of the attic, condensation forms. If there is no waterproofing, then the moisture that appears will penetrate into the insulation, which will soon become unusable.

Waterproofing materials for metal roofing

To provide waterproofing, a vapor-permeable under-roofing film is usually used under the metal tile, shown in the photo, which is placed under the roofing. designed to protect the premises located under the roof from precipitation, melt water, dirt and dust. Thanks to the film, moisture does not enter the thermal insulation layer from the outside of the building.

The product intended for roof waterproofing is a three-layer material with a woven reinforcing mesh made of polyethylene fibers. It has a polyethylene lamination on each side.

The variation of the film for waterproofing, depending on the type and thickness of the lamination, is different:

• with fire-resistant qualities;
• UV resistant;
• various colors, etc.

Typically, a roll of waterproofing film looks like a strip 50 meters long, 150 centimeters wide and specific gravity 140 g / m². It should be noted that the service life of this material is similar to that of metal tiles. Such a film does not lend itself to decay processes, fungus and mold do not form on it. In addition, it belongs to environmentally friendly products, does not affect the human body negative impact.

Metal tile - wavy metal sheets of various configurations, can be copper, aluminum, steel. Due to its qualities ( strength, durability, lightness, low price ), the material ranks first among roofing coatings.

Metal roof waterproofing is one of the most important milestones arrangement of the roof.

Roof waterproofing should always be done. Depending on the purpose of the room, the shape of the roof, the cost of materials and other indicators, waterproofing materials are classified into several groups.

Waterproofing membranes

Polymer membranes are a modern waterproofing material with microscopic perforation, which makes it possible for air to pass through the material, but not water.

There are membranes:

• anti-condensation(able to absorb moisture droplets, prevent the formation of condensation);
• diffusion(one side of the membrane absorbs moisture, the other prevents the passage of water droplets);
• superdiffusion(multilayer membranes).

Paint shop

Refers to external waterproofing. Paint waterproofing is a roof covering with paints, varnishes, various emulsions. This ensures that the roof is protected from water entering the roof. The service life of such insulation is short - up to five years. Typically, such insulation is suitable for soft roofs.

Coating

Most commonly used for flat roofs... Such insulation in the form of a bituminous mixture is applied to the roof surface in a thick layer. There is cold and hot wayapplication. The coating insulation has the property of cracking under the influence of temperature extremes, and therefore requires replacement after five years. Bitumen-polymer mixture is more stable and may not lose its properties up to 15 years.

Waterproofing film

The most common waterproofing method. Installed on the front of decking or covering.

Okleechnaya

Suitable for flat roofs. The roof is covered with roofing felt or similar material made of vinyl plastic, polyethylene, isoplast, mostoplast, polyvinyl chloride, isoelast, ecoflex. This method of waterproofing is quite economical and has a long service life.

Sprayed

It is used for surfaces with a porous structure: cement or concrete. Using a spray gun, a special impregnation is applied to the porous material, filling the smallest pores.

Under the metal tile, the most suitable waterproofing method is to lay a waterproofing layer under the metal tile. It is advisable to use membrane or anti-condensation films.

Is it obligatory to install waterproofing under metal tiles

Condensation will form inside the building without waterproofing. This applies to both an insulated metal roof and a cold one. The inner surface of the roof will start to deteriorate, leaks will appear, which will destroy the roof frame.

The main reasons on which it is imperative to lay a hydro-barrier under the metal tile are:

• preventing dust and moisture from entering the room;
• preventing the formation of condensation in the insulation layer;
• ensuring the thermal insulation properties of the roof.

Do-it-yourself waterproofing for metal tiles

Important steps in preparation for laying a waterproofing layer are:

• correct and reliable installation of the roof frame- rafter system;
• installation of the cornice and installation of the frontal board to the end of the rafter legs;
• attaching hooks gutters for gutters.

Installation of waterproofing can be done two ways:

In the first case, the film is rolled parallel to the cornice. The film is laid in such a way that it can sag to the strips of the crate. The overlap must be at least 10 centimeters wide.

To provide ventilation between the metal tile and the film, the film is fastened using a counter lattice.

The second case - laying a waterproofing film perpendicular direction of the eaves. The anti-condensation film under the metal tile is stretched over the prepared crate. With this option, the overlap should not exceed 10 centimeters.

Correctly executed waterproofing of the roof under the metal tile directly contributes to an increase in the service life and ensuring the functional loads of the roofing cake.

NOTE!

Waterproofing for metal tiles provides ventilation gaps and free movement of air flows from up to the cornice, and found an outlet in special ventilation pipes. To calculate the amount of roofing, you can use ours.

While maintaining the moisture protection of the roof, the protection of the under-roof space and the protection of the entire house are preserved.

Waterproofing the roof of the house for metal tiles in steps:

1. the roofing film under the metal tile is laid from the eaves to the ridge, observing the overlap... The film is attached to the rafters with a stapler. The overlap should fall on the rafter boards;
2. in the intervals between the rafters should be left slight slack (about 2 cm)... This ensures the integrity of the film during sudden temperature changes;
3. if an anti-condensation or diffusion film is used, then the height of the rafter system should exceed thermal insulation layer by a few centimeters. Sometimes, in order to achieve the desired height of the bars, they have to be increased;
4. waterproofing is not laid on the formwork... In this case, logs are laid along the slope at a distance of more than 1 meter;
5. on the ridge part must be at least 5 cm. The edge of the film must reach the lower groove;
6. ventilation gaps must be arranged in such a way that prevent insects and birds from entering the roof;
7. the film should be fixed with a special adhesive rubber tape;
8. film overlap on pitched joints should be 15-20 cm;
9. when equipping pipes stove heating or ventilation outlets, the film is laid with an overlap of 5 cm;
10. when laying a superdiffusion membrane, it is not necessary to provide gaps between the insulating layer. This material is laid on rafter system. When the rafters are greater than the thickness of the insulating layer, then the membrane is laid, laying it along the profile of the rafters;
11. attic windows are equipped with a waterproofing layer according to the rules of the constructive guidance of the window.

Roofing pie cutaway

Installation of waterproofing film

After laying the waterproofing, proceed to the installation of the next layer.

Experienced craftsmen share tips, guided by which, you can avoid common mistakes during work:

Guided by the rules for laying the waterproofing layer and the recommendations of specialists, it is possible to ensure high-quality performance of waterproofing works independently.

It is better to check any moments of laying with professionals who know firsthand the rules and subtleties of work.

Vapor barrier for metal tiles

Vapor barrier layer - necessary stage arrangement of a roofing cake for metal tiles.

The vapor barrier protects the penetration of vapors into the under-roof space from the side of the room.

The material is laid according to the principle of laying a waterproofing layer.

Vapor barrier film for tiles

Films must be placed in correct sequence and according to the rules for overlapping layers of the roofing cake. Replacing the steam and waterproofing layers in places ensures the ingress of moisture into the rafter system, into the heat-insulating layer, which reduces the quality and service life of the roof structure.

Useful video

DIY waterproofing installation:

Thus, the roofs of their metal tiles require the installation of waterproofing and vapor barrier layers, which ensure the reliability of the roof and dryness in the room.

All developers are wondering what to put under the metal tile in order to preserve for many years wooden elements roof structures, and the roof itself. The durability of the rafters and longitudinal beams, the air temperature in the attic in summer and winter, directly depends on the choice of the substrate for the tiles. First of all, it is necessary to follow all the recommendations of the tile manufacturer.

Of the metal tile, it includes several insulating layers, which have an important function of protecting the entire house from the negative effects of cold, moisture, and noise.

What is the role of the substrate in the operation of the house, what types of substrate are there, and in what cases is one or the other used? We will try to understand these issues.

Varieties of substrates

The substrate for the metal tile must be chosen depending on the purpose of the attic space.

There are underlays for cold rooms and there are underlays for residential, that is, heated rooms. Some requirements are imposed on substrates for residential premises (such as an attic), and others for a cold attic.

The underlayment for a cold attic is much easier than for a heated one. A counter-lattice is attached to the rafters, and a lathing is attached to it. Between them they leave free space for air circulation.

A film is placed on the crate to protect wooden structures from moisture, which penetrates into the attic through leaks in the tiles.

For a warm attic, the backing design looks different. The lathing and counter-lathing are also attached. But more stringent requirements are imposed on waterproofing. In this case, it must not only protect the attic from the ingress of moisture from the outside, but also from condensation that forms on the inner surface of the metal tile due to the temperature difference between the outside air and the inside.

On top of this, the waterproofing film must ensure the removal of water vapor rising from the lower rooms so that the insulation remains dry and does not lose its qualities.

An air space of 2 to 4 cm is left between the waterproofing and the insulation for air ventilation.

Depending on the climate in your region, choose the insulation material and its thickness. A film for insulation is laid below. And already on top of the film, the living space is sheathed at the request of the developer. This design is called "roofing cake". It is optimal for protecting the roof structure from external and internal adverse conditions.

Roofing material substrate

It fits only if there is a lathing and only with a cold roof.

Roofing material is used as a substrate only for cold attic spaces... To put or not to put roofing material under the metal tile, each developer decides for himself. It should only be noted that if the roof is cold and the attic is well ventilated, then roofing material can be put, but in this case it is necessary to provide an air cavity between the roofing material and the tiles.

If the roof is old and already covered with roofing felt, then in this case it is possible on top of it, having previously mounted the crate for the air gap.

But most experts are skeptical about such a device and believe that it is best not to put roofing material under the metal tile, because, in the end, this will lead to damage to the roof.

Roof waterproofing

A layer of waterproofing protects thermal insulation material and the entire wooden roof structure from the effects of rain and snow that fall inside when strong wind... In addition, the film prevents condensation from the inside of the tiles from entering the thermal insulation.
can be done in two ways:

1. Mount the crate on the thermal insulation and put the film on it, thereby providing a 2-4 cm gap between them for ventilation.
2. Or you can put the film directly on the thermal insulation without a gap. But at the same time it is necessary to use a special membrane-diffuser. Such a film will not allow moisture to pass from the outside and at the same time will absorb the moisture that rises from the lower rooms in the form of wet vapors.

And although the membrane-diffuser film has a higher cost compared to conventional film, it has undoubted advantages... It is laid directly on the insulation, and there is no need for an air gap. In strong winds, it significantly reduces heat loss.

Being waterproof on the outside, the film is capable of absorbing vapors from the inside, that is, such a roof will "breathe". As a result wooden structures roofs will stay dry and last much longer.

Warming and vapor barrier

The thickness of the insulation depends on climatic conditions region and reaches 20 cm.

Depending on the climatic conditions in your area, thermal insulation under the metal tiles are chosen with a thickness of 15 to 20 cm.

Insulation is made from mineral wool... It is produced in rolls or pressed plates.

The insulation is cut 10 mm wider than the distance between the rafters. During installation, it is inserted into place and, starting from the middle, gradually pressed in, trying to avoid crushing and deformation. In this case, the insulation must fit snugly to the rafters, the joints must be sealed.

To protect the insulation from moisture that rises from the lower rooms in the form of vapors, you need to put last layer from the so-called roofing cake. This layer consists of plastic film reinforced with mesh. It should be laid with an overlap of 10 cm, starting from the bottom.

To finishing material did not touch the film, the strips are attached to it and the trim is already attached to them.

Ventilation under the roof

The waterproofing film / membrane protects against moisture from the outside, the vapor barrier protects against internal moisture. Installing this double-circuit insulation provides top and bottom air inlet / outlet.

There must be ventilation under the roof. This is due to several reasons:

1. Ventilation removes moisture from under the roof. Moisture leads to corrosion metal structures and to the destruction of concrete and brick parts.
2. Ventilation evens out the temperature under the entire roof and thereby prevents the appearance of ice, as it damages the roof and the drainage system.
3. V summer time the temperature in the attic room decreases.

Ventilation air enters through the cornice lining and exits through the ventilated roof ridge. If the air outlet is not provided in the ridge, that is, a "dead ridge", then in this case, roof valves are installed.

They are used both on cold and insulated roofs for metal tiles. There are also valves that can be installed on the roof ridge.

Roofing errors

Typical mistakes that must be avoided when constructing a "roofing pie":

1. In no case should you put a vapor barrier film instead of a waterproof one. In this case, moisture that has got into the insulation will remain in it;
2. Also, you cannot put a waterproofing film instead of a vapor barrier. In this case, the roof will not "breathe".
3. Do not put the membrane-diffuser film on the contrary. And in this case, moisture gets into the insulation and remains there.
4. It is imperative to observe the number of all ventilation gaps in the "roofing pie". Since the metal tile is very afraid of the appearance of moisture on its back.
5. Don't skimp on roofing. It has long been known that the miser pays twice. By purchasing cheap substandard goods, in the future this will result in expensive repairs.

It is much easier to do well right away than to fix it later.

If you equip the roof according to all the rules, then it will serve you for many years, keep warm in your house in winter bad weather and give coolness in the summer heat.

Metal roofs are a practical and attractive solution for a private townhouse, country cottage or small apartment building. However, each roofing master will confirm that the use of this material without the organization of competent waterproofing will lead to a decrease in the life of the structure, problems with the rafter frame and the roofing itself. To protect the rafters from the ingress of atmospheric moisture and condensation, waterproofing is laid under the metal tile. In this article, we will tell you what waterproofing materials exist, how to choose and apply them correctly.

Metal tile - a material for roofing on the basis of galvanized steel, covered with paint or polymer with a wavy relief. It has a high thermal conductivity, therefore, due to the temperature difference inside and outside the house, it becomes covered with condensation, which significantly reduces the service life of the roof. If you do not install the waterproofing film, the following occur unpleasant consequences for the roof:

1. Dampness of the rafter frame. If condensation gets on the rafters, the wood will absorb excess moisture, which leads to the spread of mold, mildew and decay of the frame elements. Ultimately, this results in irreversible deformation of the roof structure.
2. Moisture penetration on the thermal insulation material. If the insulation does not protect the waterproofing film or membrane, it damp over time, which reduces its effectiveness by half. It should be borne in mind that the properties of the thermal insulation material are not restored even after complete drying.
3. Corrosion of roofing material. If you do not install waterproofing, condensate accumulates on the inner surface of the metal tile roof, from contact with which metal cover starts to rust. The most vulnerable areas for corrosion are the places where the roofing material is attached to wooden rafters... Rust, gradually corroding the metal tile, significantly reduces the durability and reliability of the roof of the house.

Important! Waterproofing for metal tiles - prerequisite durability, reliability and quality of the roof made of this material. If no waterproofing sheeting or membrane is used to protect the rafters and insulation, the lifespan of the roof covering is more than halved.

Views

Modern construction market offers a wide range of waterproofing materials that differ in price, properties and application. The choice depends on the type of roofing cake of the house and the financial capabilities of the buyer. To protect the rafters, insulation and roof covering from condensation, installation is carried out:

Note! If the roof structure is of the warm type, then only vapor-permeable materials can be used as waterproofing. In addition, the installation of the waterproofing film is performed so that between it and roofing material there was a ventilation gap. Waterproofing under the metal tile should not come into contact with either the roofing or the insulation.

Installation technology

Waterproofing material is used to protect the rafters and roof insulation from contact with condensation or atmospheric moisture. Installation of waterproofing is carried out after the assembly of the rafter frame, but before the roof covering is laid. The technology for laying waterproofing material is as follows:

1. The film or membrane is cut into strips, the length of which corresponds to the length of the slope plus 10-15%.
2. Waterproofing under the metal tile is carried out with sagging, so that in the event of a leak, water pressure does not lead to rupture of the film or membrane.
3. The film or membrane is laid in strips perpendicular to the rafter legs of the roof with an overlap of 10-15 cm.
4. The waterproofing film or membrane is fixed along the roof rafters with construction stapler with high quality stainless steel brackets.
5. Roofing material is nailed to the rafters with ordinary or galvanized nails.
6. The joints between the strips can be glued with a moisture-resistant sealant, construction tape, or left as is.
7. After laying the film or membrane along the rafters, the counter battens are installed to create a ventilation gap.

Please note that without properly organized waterproofing, the service life of a roof with a metal roofing is significantly reduced. This simple, inexpensive measure allows you to maintain the performance of roofing and insulation for longer, which will save a lot of money usually spent on repairs.

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