Do you need a vapor barrier under a cold roof? Features of roof waterproofing for metal tiles: schemes, materials, installation technology Roofing film for metal tiles which is better

Nowadays, metal tiles are often used to decorate the roofs of buildings - the material is reliable and beautiful. However, the durability of any roof and its operational characteristics largely depend on how correctly the under-roof space is made. Roof waterproofing for metal tiles is one of the main elements that should not be forgotten during the construction of a building for any purpose.

Why is it so important to have a waterproofing layer under the roof, including under the one that will be formed with metal tiles? Is it really not enough just one finishing material to drain water? So, waterproofing performs several functions, providing reliable protection for the roof, the space under it and the inside of the structure.

The main function is protection of all elements located in the under-roof space from moisture... The roof is far from the easiest construction to perform, and its structure is multilayer. During construction, wooden boards, bars or metal elements are used as rafters and beams, as well as to create the lathing. Both materials strongly dislike excess moisture. And waterproofing will provide reliable protection of these elements from it.

Attention! If the roof is insulated, then inside its pie there are both heat-insulating and insulating materials. They also do not like moisture and only a waterproofing layer is able to provide them with protection from its effects.

Correctly installed waterproofing will also allow get rid of the accumulation of condensation moisture in the under-roof space... It forms due to the temperature difference between the inside of the house and the street and can also have a negative impact on all materials used in the construction of the roof. Condensation can gradually destroy them and cause leaks and reduce the life of the materials.

On a note! The waterproofing layer will make it somewhat easier to convert the attic into an attic space, if such a desire arises from the owners of the house.

Materials used

We have found out that waterproofing is the most important element of a metal roofed roof. But what should be a quality layer that protects from water? The requirements for waterproofing are as follows:

• it must have increased refractoriness;
• steam is good;
• strength and reliability indicators should be at their best;
• the material should not deteriorate during sudden temperature changes, be afraid of ultraviolet radiation;
• the layer must withstand a certain level of mechanical stress;
• waterproofing should not be afraid of pest attacks or be susceptible to mold development;
• also, she must cope well with her main tasks and not harm human health.

Various types of materials can be used for waterproofing. They all have a lot of differences from each other, including different resistance to light, strength, quality and durability.

For the most part, special under-roofing films that have several layers are used for waterproofing metal roofs. There are reinforcing and absorbent layers here. The first provides protection from precipitation, and the second is able to absorb moisture coming from the inside, due to which condensation cannot accumulate on the waterproofing and mold foci can form. Also on both sides, the material is usually polyethylene lamination.

Such a coating has special pores that allow the passage of vapors that form inside the house, but at the same time do not allow moisture coming from outside to spoil the materials from which the roof is made. This feature of the material, called vapor permeability, is especially important if the attic is converted into an attic and is used as a residential one.

Advice! When choosing a material for waterproofing, it is important to pay attention to its service life. It should coincide with the service life of the metal tile, so that you do not have to disassemble the roof and re-lay the waterproofing if it fails, and the main roofing material will still be usable. The service life of a special film used under metal tiles is 50 years.

Name	Short description
	A film with low vapor permeability, for which it is important to equip the so-called double-circuit ventilation, which will be located between the roofing and waterproofing materials, as well as between the film and the insulation layer of the roof. The gaps between them should be 3-5 cm. The material is ideal for the construction of a cold roof or a roof with a simple structure.
	Material that also requires the creation of dual-circuit ventilation. The film is equipped with a moisture-absorbing fleecy layer that perfectly retains excess water. This is a fairly dense material, rough to the touch, durable and not afraid of exposure to ultraviolet radiation. But the vapor permeability of such a film is low.
	The best material for roof waterproofing, as it has increased vapor barrier performance and does not require the arrangement of double-circuit ventilation. It is enough to leave gaps between the film itself and the roof covering. Installation of such a film is simple, it has a long service life. The main disadvantage is the high price.

On a note! Hydrobarriers that are widespread to this day, made on the basis of bitumen and bitumen mastic, should not be used for arranging a roof made of metal tiles.

Of course, for a temporary roof, you can use a cheaper film, but for capital construction it is better to take high-quality, albeit expensive, material. It is not worth saving here and it is better to buy a diffusion membrane coating. All indicators of the purchased film are shown on the edging tape that frames the material. The film is produced in rolls 1.5 m wide and 50 m long. The density of the material is about 140 g / m 2. A striking representative of the material optimal for laying under metal tiles is Izospan AM or AS.

Prices for underlay waterproofing films

Roof waterproofing film

Preparation for work

Laying the waterproofing layer requires preparatory work. They include the creation of a rafter system, designed according to preliminary calculations, the installation of eaves and end boards. Only after that the waterproofing is laid.

Certain tools are useful for installing waterproofing. This is a tape measure, scissors, a hammer, a marker, a construction stapler, a screwdriver. You will also need to purchase bars and screws.

Styling process

The installation of the layer can be carried out in two ways: in the first case, the film is laid directly on the rafters in strips parallel to the cornice, and is attached with a slight sagging between the rafters. If it is necessary to leave a ventilation gap between the metal tile and the film, then the film is fixed on the overhead counter-lattice. Also, the film can be mounted perpendicular to the eaves strip. It fits here on the finished crate and is fixed in tension.

Let's consider how the installation of a waterproofing layer under a metal tile takes place using a detailed example.

Preparatory work

Step 1. According to the project of the house, a truss system is being built. In this case, it is made of wood, which especially needs protection from moisture, so the question of laying waterproofing is not worth it.

Step 2. Installation of a vapor barrier layer is in progress. The special film is attached with construction brackets around the perimeter of the building under the rafters and directly to them. Work is carried out on the inside of the roof. The roll is neatly rolled out and the film is mounted on its intended place.

Step 3. Separate strips of vapor barrier must be laid with an overlap on each other, while all overlaps, as well as joints of the material with all structural elements of the roof (pipes, ventilation, etc.) are hermetically glued with adhesive tape.

Step 4. On top of the film, counter-lattice slats are nailed to the frame - it is on them that the entire interior decoration of the attic space will be fixed.

Step 6. The thermal insulation is placed on the vapor barrier between the rafters. Laying is done very tightly in order to reduce the number of cold bridges. This concludes the preparatory work.

Prices for thermal insulation materials

Thermal insulation materials

Laying the waterproofing layer

After all the preparatory work, the waterproofing film is installed. In this case, the Tekafol Super membrane is used as a material that protects against moisture.

Step 1. A roll of membrane is rolled out on the surface of the insulation along the eaves of the roof. It is important to lay the material on the right side, which will be determined by the installation instructions for the selected type of film (usually the material is fixed with that side to the roofing, where the edge tape has a bright and saturated color). The film is laid with slight sagging (about 2 cm). This measure will allow you to get rid of excessive tension and tearing of the material in the event of a sharp temperature drop.

Attention! The film should be installed on the right side initially. It is impossible to twist and turn it over during installation, since it will lose some of its waterproofing properties.

Step 2. The foil is fixed to the wooden rafters with a construction stapler. You can use wide-headed nails instead.

Step 3. Next, a second strip of waterproofing is spread. It fits with an overlap on the first one (15 cm). If the slope of the slope does not exceed 30 degrees, then the overlap between the individual layers should not be less than 25 cm. The joints can be additionally glued with double-sided adhesive tape.

Step 4. The second strip of the waterproofing membrane is fixed. Thus, the film covers the entire heat insulation material. In places where pipes, hatches and other structural elements are located, it is required to securely fix the material. It is also important to remember that the waterproofing layer is not brought to the ridge of the roof - there should remain a ventilation gap of 5 cm. It will be covered with a ridge strip.

Step 5. Along the rafters, directly through the waterproofing film, lathing bars with a cross section of 4x5 cm are attached with self-tapping screws.They additionally fix the film on the rafters.

Step 6. Across the lathing bars, counter-lattice bars are attached with a step of 35 cm - it must correspond to the step of the metal tile. Further, the installation of the tiles itself is carried out directly.

It is worth remembering that a gap of 5 cm must be maintained between the tiles and the waterproofing. Otherwise, the required air circulation will not be ensured. There may be no gap above the insulation if a high-quality diffusion membrane is used.

Video - Installation of a hydro-barrier

Rules for installing a hydro-barrier film

When working with waterproofing, it is important to remember several installation rules:

Cold roofs - do you need waterproofing?

The answer to this question will be unequivocal - a waterproofing layer is needed in any case. But since in this case there will be no insulation in the roofing pie and good ventilation of the materials will be provided, you can use roofing material or glassine, which will cost less than expensive film. But in this case, the formation of a ventilation gap between the roofing material and the metal tile is required.

Waterproofing is a very important layer in the roofing pie of a metal roofed roof. They should not be neglected, so that later there will be no problems with leaks or a reduction in the service life of the materials used to create the roof.

Prices for metal tiles

Metal tile

Video - Installation of a roof made of metal tiles

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 the roofing decking made of this material from the side facing the inside of the attic space, 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. On each side, it has a polyethylene lamination.

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

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

Typically, a roll of waterproofing film looks like a strip 50 meters long, 150 centimeters wide and 140 g / m² specific gravity. 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 have a negative effect on the human body.

Metal tiles and decking are based on a metal sheet.

On both sides it is covered with polymer material, which is not able to improve the thermal insulation qualities of a thin roof. Therefore, such roofs are mandatory.

However, an ill-conceived and laid with errors insulating cake can lead to rapid corrosion of the metal.

Correctly selected and correctly applied waterproofing will help to avoid problems.

Qualitatively laid roof does not protect from moisture penetration under its sheets. Water will be inevitable seep through the overlaps at the joints and at the attachment points.

The appearance of moisture on the reverse side of the roofing sheet would not pose a danger if it had the ability to quickly evaporate from there, as it happens from the outside of the roof. However, a roofing cake implies a thick layer of porous insulation that perfectly absorbs and retains a significant amount of water.

Therefore, the underside of the roofing material will be continuously exposed to fumes from the slowly drying insulation. And this will greatly accelerate corrosion even in the presence of a polymer coating.

Waterproofing helps to reduce the amount of moisture in the roofing cake. Water penetrating under the roof will simply flow down and out. At the same time, the insulation will remain dry and not only will not turn into a corrosion catalyst, but also will keep its thermal insulation qualities.

What types of waterproofing materials exist

Among the methods of waterproofing roofs (), the following are most common:

• Oleechnye... The first options were glassine and roofing felt, but now they have been replaced by polymer bituminous coatingssupplied in rolls. Stick them heating or using binders;
• Painting... The method consists in applying viscous materials directly to the roof surface. Layer thickness - about 2 mm... More often used on flat concrete roofs;
• Sheet waterproofing... It is used on roofs with heavy loads. The method consists in welding of waterproofing sheets into a single canvas. Both metal sheets and plastic can be used;
• Film waterproofing... The most rational way to waterproof pitched roofs. Consists of the installation of sheets of moisture-proof film or membrane. The film is located between the roofing material and the insulation layer.

Due to the successful combination of low cost, durability and excellent waterproofing the latter method is most widespread in both industrial and residential construction.

Waterproofing the roof of the house for metal tiles

Roof waterproofing for metal tiles begins with the choice of waterproofing material. What is the best waterproofing for metal roofing? When laying metal tiles, the following types are used film waterproofing:

• Classic polymer films... Relatively cheap, but during installation they require the arrangement of double-sided ventilation: the film should be at a distance of several millimeters both from the metal tile and from the insulation located below;
• Anti-condensation films... They differ from ordinary ones by the presence of fine pile on one side. The villi help to absorb steam from the space between the film and the roof, thereby preventing it from condensing on the metal. During installation, they also need a double-sided ventilation device;
• Auperdiffusion membranes... Their main difference from classic films is the ability to pass a certain amount of steam through themselves, while maintaining impermeability to condensate drops and water penetrating from the roof.

What kind of waterproofing to choose for a metal roof is up to you. The choice between these materials depends on the installation conditions, i.e. from the ability to arrange double-sided ventilation. The financial factor also affects: classic films are always cheaper superdiffusion membranes and anti-condensation films.

Roof waterproofing for corrugated board

Owners often ask themselves - is it possible to cover the roof with corrugated board without waterproofing? In general, the corrugated board often overlaps, with an approach of 10-15 centimeters, which helps to avoid moisture penetration.

But these joints are still not tight and moisture penetration is only a matter of time. Therefore, roof sealing is mandatory.

What kind of waterproofing to choose for roofing from corrugated board?

There are no fundamental differences in the requirements for waterproofing roofs made of corrugated board and metal tiles. Therefore, it is allowed to use exactly the same materials. However, some peculiarities should be considered:

• sheets of corrugated board are much easier to seal together, therefore less moisture penetrates under them;
• there are fewer attachment points, which also reduces water penetration;
• service life of high-quality corrugated board is longerthan metal tiles. Accordingly, it makes sense to focus on a more durable waterproofing.

What is the difference between cold and mansard roof waterproofing?

Often the owners have a question - do you need waterproofing for cold roof sheeting? The answer is yes, we do., but there are a few nuances.

If the attic is not heated, then in this case only one function is assigned to waterproofing - to prevent water leaks from the side of the roofing material. Therefore, only one layer of waterproofingfixed between the battens and the roof counter battens.

In order for the water rolling down the film to escape outward, a overlap of waterproofing on the eaves. The size of the overlap is 40 mm.

In the case of a heated attic, there is also a warming cake under the roof. not only from moisture coming directly from the roof, but also water vaporacting from a warm attic. Therefore, here you will need an additional one, placed between the insulation and the room.

Cold Roofing Pie

Fastening the insulating membrane with a construction stapler

Waterproofing technology

The process of laying waterproofing begins with the preparation battens for battens and counter battens... To do this, a timber with a section of 20-30 mm is cut into pieces of the required length and treated with a fire retardant compound and an antiseptic. Further, the sequence of actions will be as follows:

1. over rafter structures horizontal crate is stuffed;
2. the overlap is actually laid waterproofing material... In this case, one should be guided by the markings applied to the film, which indicate the upper and lower sides of the waterproofing. Laying starts from the bottomso that the top sheets can form a waterproof overlap... If there are dormer windows in the roof, they will be bypassed with additional fasteners with a stapler and sealing with tape;
3. the vertical counter-lattice from a bar of a slightly smaller sectionthan the main crate. We recommend reading a more detailed article about.

Counter-lattice slats are nailed not close to each other, and with small gaps between them. In this case, they are guided by the rule: one centimeter of free space should fall on one meter of the rail. This will allow air circulate freely under the surface of the roof and carry away the drying moisture.

Do you need waterproofing for cold roof metal tiles? As in the case of roofing sheeting, the installation of a waterproofing membrane is required, because roof joints are not tight and can leak water.

For the insulated attic, you will need to perform more a series of steps:

1. after laying the insulation on the inside of the rafters, the entire pie is covered. To seal the seams of the vapor barrier, they are glued with tape. The canvas is attached to the rafter structures with a construction stapler;
2. the roof is sewn up from the inside with plywood, moisture-resistant plasterboard, PVC panels, etc.

Then proceed to the interior decoration of the attic.

Skylight Roofing Pie

Laying the waterproofing membrane

Useful video

We bring to your attention a video on sealing a metal roof:

Conclusion

From quality waterproofing metal roofs in many ways its service life depends... This is especially important in cases with insulated roofs, where double-sided waterproofing of the insulation is required. Therefore, it is necessary not only to choose the most suitable material, but also not to deviate from the technology of its installation.

Metal tiles - 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.

The device of a roof for metal tiles provides for the correct laying of vapor barrier, heat insulation, waterproofing layers. Each material should be laid in accordance with the installation rules. Then the roof will last a long time, and the house will be warm and dry.

If you have not yet decided on the choice of coverage, you can read the article in which we compare the characteristics of metal and soft roofing.

Waterproofing a roof made of metal tiles is one of the most important stages in arranging a roof.

Types of waterproofing materials

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.

• 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. Painting 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. Usually such insulation is suitable for soft roofing.

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 a cold and hot way application. 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 rafter system in front of the decking of the roofing cake or covering.

Suitable for flat roofs. The roof is covered with roofing felt or a 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 laying a waterproofing layer under the metal tile. It is advisable to use membrane or anti-condensation films.

Is it necessary to install waterproofing under the metal tile

Condensation will form inside the building without waterproofing. This applies to both the insulated metal roof and the 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 out 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 increases the service life and ensures the functional loads of the roofing cake.

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 a house for metal tiles in steps:

1. roofing film under the metal tile is laid from eaves to ridge with 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, leave slight slack (about 2 cm)... This ensures the integrity of the film during sudden changes in temperature;
3. if an anti-condensation or diffusion film is used, then the height of the rafter system should exceed a heat-insulating layer by a few centimeters. Sometimes, 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. along the ridge part, the ventilation gap 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. fasten the film with a special adhesive rubber tape;
8. the overlap of the film at the pitched joints should be 15-20 cm;
9. when equipping furnace heating pipes 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 the rafter system. When the rafters are greater than the thickness of the insulating layer, then the membrane is laid, laying it along the rafter profile;
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 tipsguided by which, you can avoid common mistakes when working:

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

Vapor barrier for metal tiles

Vapor barrier layer - a necessary stage in arranging 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

The films must be laid in the 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 thermal insulation layer, which reduces the quality and service life of the roof structure.

Waterproofing for metal tiles: the choice of an anti-condensate under-roof film and its installation

Details about waterproofing for metal tiles: the choice of waterproofing for the roof, laying and installation of the under-roofing film. Do I need an anti-condensate hydro-barrier under a metal roof and advice from experienced craftsmen.

When using a metal roofing carpet, condensation forms on the inside of the covering. And this process does not depend on the person in any way. There will be condensation anyway. Correct placement of waterproofing underneath the metal tile will help prevent its formation. And, at a minimum, it will prevent moisture from seeping into the roofing carpet.

Characteristics of a waterproofing film

Roofing film, whatever it is made of, should protect the attic space and the thermal insulation layer. In other words, so that processes do not begin under the metal tile that will eventually destroy it and have a detrimental effect on the base of the roof, special protection is needed.

A priori, the properties of waterproofing for metal roofing are microperforation to ensure ventilation of water vapor. To achieve this result, the substrate under the metal tile must

• Consist of several layers
• Have a reinforcing polyethylene grid

The thickness of each layer varies depending on the type of film. Moreover, in addition to removing moisture, a protective waterproofing film may have

Each manufacturer indicates what qualities are inherent in its material.

Types of waterproofing substrates

In a high-quality roof, it is necessary to provide for the formation of condensation not only directly under the metal tile, but also on the side of the insulation. For this, first of all, an anti-condensation layer is applied to the film from the inside and a gap is left for ventilation.

The formation of condensation depends on whether the roof is warm or cold. Its intensity and volume are directly related to the temperature at the top and bottom of the substrate.

In total, there are three types of films:

• Classic film. It is important to observe ventilation in two circuits:
  • Between roofing material and waterproofing
  • Between waterproofing and insulation
• The membrane is diffusion. She has a high vapor permeability. Therefore, the ventilation gap should only be between the membrane and the roof covering.
• Anti-condensation film. Here, the basis of the material is a fleecy moisture-absorbing layer and double-circuit ventilation is important for it

It is also accepted to separate the substrates directly from the type of roofs. In this case, the following is taken into account, whether the roofing cake

Underlay and "warm" roof

If the roof is heated from the side of the attic (most likely, this is a residential area), the roofing cake is constructed in stages and is quite difficult. So, how to install waterproofing under metal tiles? Installation consists of the following steps:

Substrate and cold roof

The roofing cake for cold roofs is made in a more simplified way, which means it is done faster. The layers in this cake will be like this:

1. Creation of lathing and counter lathing
2. Laying the waterproofing layer
3. Creating a rafter system

If there is an unheated attic under the roof, almost any film can be used as waterproofing:

• Anti-condensation
• Diffusion membrane
• Any material that can keep moisture out, including roofing material or greenhouse film

Roofing material substrate

Roofing material is understood as a material that consists of cardboard (fiberglass or fiberglass), coated with bitumen or polymers. The service life of such a material as a roofing covering is from one to three five years. As a substrate, it can even last a little longer, since it will not be in contact with the sun.

Roofing material is a fairly popular material for creating a primitive waterproofing layer in a "cold" roof.

The disadvantages of roofing material, which even a low price cannot neutralize, include the fact that

• Over time, moisture will damage the integrity of the bituminous coating
• The cardboard base will resist (fiberglass will withstand more time than cardboard, but it is not durable without a top coating)
• Refers to the category of fire hazardous materials

As a waterproofing layer, roofing felt and its analogs can only be used in the "cold" roofing cake.

Tips for installing waterproofing under metal tiles

The selected roof waterproofing for Country or Rukki metal roof tiles must be fixed so that air flows can easily pass through the ventilation openings. They must be installed at the highest point on the roof.

To avoid material rupture at low temperatures, the film must be laid so that there is a sag of 2 centimeters between the rafters.

The film must be laid from the eaves to the ridge, making an overlap of 1.5 centimeters at the joints. Fasten the joints with either adhesive tape or a construction stapler.

Insulation and vapor barrier for the roof

Insulation in the roofing cake, regardless of whether the roof is heated or not, should always be present. This material, even of the smallest thickness, has low thermal conductivity.

Moreover, the farther north the region, the greater the thickness of the insulation, as well as the possible number of its layers. All of them must be performed in a checkerboard pattern. And the joints must be foamed.

The insulation will be able to perform its functions of retaining heat only when there is waterproofing in the roofing cake (as described above), and for a "warm" roof and vapor barrier.

We are talking about film-type materials. Their task is to maintain the required level of thermal insulation background.

In other words, they are an important participant in the ventilation system of the roofing cake with moisture-blocking functions.

The roof must be strong, capable of protecting the house from snow, wind, rain. The metal tile can perfectly cope with such functions, but provided that the roofing cake is made in compliance with the technology. This means that it necessarily contains waterproofing, as well as insulation and, in some cases, vapor barrier.

Before doing further installation work, think about how to cut the metal tile. The wrong tool can shorten the life of the material. Three options are suitable for cutting: die-cut or electric scissors, as well as a drill attachment. It is prohibited to cut metal tiles with a bulgakro!

For cutting other elements that are needed for the installation of metal tiles, the use of a grinder is also prohibited. For example, metal scissors are suitable for a valley. Read more about the installation of metal roof valleys here. This element must be performed as correctly as possible so that the roof does not leak.

Laying waterproofing under metal tiles

When making a roof from metal tiles, it is very important to lay a waterproofing layer.

It protects the rafter system and insulation from moisture.

If this is not done, then after a while the quality of thermal insulation will decrease and the rafter system made of wood will begin to rot.

Roof device

When installing a roof made of metal, as a rule, a vapor barrier film is used, laid on the rafter legs. It is attached with a construction stapler.

If a layer of insulation is fixed from the inside of the attic space, then such a film provides protection against condensation accumulating on the inside of the metal roof.

Waterproofing for metal tiles is a non-woven material with microscopic holes. These openings do not release warm air from the inside of the room, and at the same time, they prevent moisture from entering the room.

The vapor barrier under the metal tile has three layers: a two-layer coating of perforated polyethylene and a base.

There is also a vapor barrier material coated with aluminum foil. It has several layers:

• Reinforcing mesh;
• Aluminium foil;
• fire-resistant paper;

This film provides wind protection and reflects heat. It is perfect for creating a vapor barrier in insulated pitched roofs.

Before laying the waterproofing under the metal tiles, read the instructions for its use.

The fact is that for some films, the outer and inner sides work differently: at the steam inlet and at the outlet. Therefore, it is very important not to confuse the sides.

Laying the waterproofing layer

Almost all vapor barrier films are laid using the same technology, since they protect the thermal insulation layer from condensation.

But at the same time, vapor barrier materials are made by various methods and have certain differences in their design.

Therefore, they require a different styling technology.

If the vapor barrier has one side smooth, the other rough, then in this case it is laid with the smooth side to the heat-insulating layer.

First, the vapor barrier is fixed with galvanized nails or a stapler. However, the final fixation is performed with counter-lattice slats. These slats create a ventilation gap.

It is desirable that the cross-section of the bars of the counter-lattice be 4x5 centimeters.

In any case, the ventilated space under the metal tile must have a height of at least 4-5 cm.

Waterproofing for metal tiles is mounted in horizontal rows. It is fixed from bottom to top parallel to the roofing ridge. The overlap of the panels should be 10-15 centimeters. Some manufacturers recommend laying the vapor barrier in vertical rows. In this case, the overlap of the panels should be 15-20 centimeters.

It should be noted that the joints must be glued with a special adhesive tape or double-sided tape, regardless of the order of laying the vapor barrier.

It is necessary to pay particular attention to the places where the roof adjoins to chimney or ventilation pipes, parapets, dormers and other elements of the roof. In such places, it is imperative to glue the joints of the vapor barrier with adhesive tape.

Waterproofing the roof of the house for metal tiles

The main task of waterproofing the roof of a house for metal tiles is to protect the rafter system and the installed thermal insulation material from the harmful effects of moisture. Moisture can penetrate under the roofing material both from the outside (rain, snow) and from the inside in the form of condensation.

An example of a roofing device.

There is an opinion that the waterproofing in the roofing cake is an additional layer, that is, it is not necessary to install it. However, this statement is fundamentally wrong. A hydro-barrier can be dispensed with only if the attic space is unheated. In the case of a residential attic, waterproofing is a must.

Some developers use ordinary roofing felt instead of a special film. Although it is less expensive, its performance and service life leave much to be desired. Therefore, it is better to make a high-quality hydro-barrier right at the stage of roof construction and forget about it than to constantly have problems with roofing material.

Waterproofing functions depending on the purpose of the attic space

Waterproofing film properties.

Despite the use of various materials, waterproofing for metal tiles is designed according to the same principle. Only the constituent elements of the roofing pie may differ, the installation of which depends on the purpose of the attic: whether the attic will be used as a living space or not.

If the attic is uninhabited, that is, it is not planned to heat it in the cold season, then only the rafter system, hydro-barrier, counter-lattice and the roofing material can be included in the roof structure. The air gap obtained between the metal tile and the film performs the function of natural ventilation, preventing the formation of condensation. In this case, waterproofing is a reliable protection of the attic space from precipitation.

In the case of a heated attic, the main elements of the roof are:

• vapor barrier - protects the insulation from condensate rising from the inside;
• thermal insulation - reduces heat loss through the roof;
• waterproofing - prevents moisture penetration through metal tiles;
• rafters, lathing and counter-lathing are not only the load-bearing elements of the roof, but also create a ventilation layer between the insulation, the hydro-barrier and the metal tile;
• roofing material.

Film waterproofing properties

Roof device diagram using waterproofing film.

In most cases, a special three-layer laminated film is used as a waterproofing material for metal tiles, which has the following advantages over other types of waterproofing:

• excellent moisture resistance;
• vapor permeability;
• high strength and wear resistance;
• fire safety;
• environmental safety;
• resistance to temperature changes;
• protection from mold, fungi and other harmful microorganisms;
• simple installation;
• long service life.

The vapor permeability of the material is considered to be no less important quality than moisture resistance, especially when using a waterproofing film under a metal tile for heated attics. Water vapor, which is formed in the process of human life, rise to the roof and accumulate in the insulation. Due to the difference in temperatures outside and inside the room, steam is converted into condensate, which not only increases the thermal conductivity of the insulation, but also leads to its destruction. To prevent this process, ensure that vapors escape freely to the outside.

The film hydro-barrier is produced in rolls 50 m long and 1.5 m wide. At the same time, its density is not less than 140 g / m 2.

Varieties of roofing waterproofing for metal tiles

Waterproofing for metal tiles.

Today on the market you can find materials for roof waterproofing, both domestic and imported, differing in technical characteristics and cost. The most popular materials are:

• glassine;
• polyethylene and polypropylene films;
• polymer membranes.

Let's consider each option in more detail.

Glassine. In the recent past, roofing material and glassine were widely used as a roofing hydro-barrier. However, these materials are characterized by fragility and low strength, so today they are used only in the case of a very limited budget or when designing temporary overlaps.

Polyethylene. A sufficiently strong and dense material, which is one of the most popular waterproofing agents not only for roofs, but also for floors, foundations and other structural elements of a building.

Chimney duct waterproofing.

Polyethylene film is produced in the following types:

1. Perforated. Has micro-holes, due to which the vapor permeability of the material increases. Its use is associated with some difficulties:
2. with high dust content of the air, micro-holes are clogged, as a result of which the throughput of the film decreases;
3. with mechanical damage, its moisture resistance is lost;
4. installation of the film involves the creation of a ventilated gap.
5. Non-perforated. They differ in lower cost and worse vapor permeability, therefore they are recommended for use in unheated rooms.
6. Reinforced. They are characterized by increased strength and throughput, so that they are successfully used when installing waterproofing under metal tiles in rooms with a high level of humidity (for example, in baths).

Polypropylene. It is used for the same purposes as polyethylene films, but it has greater strength, as well as resistance to sunlight. Some brands of polypropylene films have an anti-condensation layer. In this case, one surface of the material will be smooth and the other fibrous. This film should be installed with the smooth side up.

Polymer membranes. Refers to a relatively new waterproofing material. According to their characteristics, they resemble natural leather. The membranes have a non-woven structure and perfectly pass all the steam from the inside to the outside. At the same time, external moisture cannot seep through them. This material can be laid directly on the insulation, that is, without creating an air gap. However, an air gap must be mandatory between the metal tile and the hydro-barrier, otherwise the roofing material will begin to rust.

Installation of waterproofing film for metal tiles

The connection of the sheets of the vapor barrier film to each other.

It is necessary to lay the film horizontally, moving from the eaves to the ridge of the roof. In this case, the cornice and the ridge must also be covered. Installation is carried out directly on the rafter system, to which the hydro-barrier is attached using a counter-lattice. This allows you to create the required air gap of about 5 cm between the metal tile and the film.

The roll is rolled without stretching. The material should sag by about 25 mm between the lags. This approach will protect the film from damage during severe temperature changes. The overlap of the material during installation should be at least 15 cm. It is done along the colored strip on the film. To fix the waterproofing film, it is recommended to use a construction stapler and special waterproof staples, although you can also use stainless steel nails.

The logs to which the film will be attached must be installed in increments of no more than 120 cm. If the finishing surface is flat, then you will additionally need to lay the logs, allowing you to get a ventilation gap and the desired degree of sagging of the material.

If the roof is equipped with skylights, then the hydro-barrier near them must be mounted so as to exclude the appearance of non-ventilated areas.

This is achieved by drilling side holes in the rafters above and below the window or by installing special ventilation holes for metal tiles in these places.

Correctly executed waterproofing for the roof under the metal tile is the key to reliable protection of the heat-insulating material and the rafter system from the destructive action of moisture. Remember to run the film with the bright side of the tape facing up. Otherwise, the effectiveness of the hydro-barrier will be reduced.

Waterproofing the roof of a house for metal tiles: installation, how to choose (video)

The main task of waterproofing the roof of a house for metal tiles is to protect the rafter system and the installed thermal insulation material from the harmful effects of moisture.

The use of metal roof tiles will be a practical and attractive solution when arranging a private, country or apartment building. Nevertheless, every craftsman knows that laying such material without thoughtful waterproofing will reduce the service life of the entire structure, as well as the roofing itself.

In this material, we will talk about how to protect the rafters from moisture penetration by laying roof waterproofing under the metal tile.

What functions does roof waterproofing perform?

Metal tile is a galvanized material for roofing. To protect against corrosion and give the material an attractive appearance, the metal tile is coated with paint or polymer. She has a high thermal conductivity, which quite often becomes the reason for the appearance of temperature drops from the outside and inside of the house. Because of this, condensation appears, which significantly reduces the life of the roof.

Without laying a waterproofing membrane under the metal tile, the following problems may arise near the roof:

1. Damage to the rafter system... When condensation enters the rafters, it is absorbed by the tree, which causes mold and rotting of the entire frame.
2. Ingress of moisture on thermal insulation... If the insulation is not protected with a water-repellent layer, then after a while it begins to damp, which greatly reduces its effectiveness. Also keep in mind that the properties of the insulating material will not recover even if it is allowed to dry.
3. Rusting roofing... Without waterproofing, on the inside of the roof, condensation accumulates on the metal tile without obstacle, which causes slow metal corrosion. The fastest and most damaged places are where the material is attached to the wooden rafters. Rust, as everyone knows, significantly shortens the service life, as well as the reliability of the roof.

You should definitely take into account the fact that the installation of waterproofing under the metal tile should be done in any case, if you are going to achieve maximum durability and reliability of not only the roofing, but the roof as a whole. Without the installation of moisture-repellent material, the service life of the roof is at least halved.

Types - which is better to choose for the roof

Currently, on the market you can find a huge assortment of waterproofing materials that differ in cost, properties and scope. What is the best waterproofing for metal tiles to choose will depend on the type of roofing pie erected, as well as on the finances that you are willing to spend on this material.

For waterproofing, you will need to install one of the following materials:

• Roofing material... Lining roofing felt is considered the cheapest, it has high water resistance and strength. It is used, as a rule, if a cold roof is installed, since the material is also a barrier for steam. Experts advise laying roofing material under the metal tile only in cases where there is no other way out.
• Film... They make a polyethylene construction film - it perfectly protects from moisture. It is used most often because it is inexpensive and lasts long enough. The film for moisture insulation is afraid of ultraviolet radiation, which makes it vulnerable to the sun - it starts to deteriorate.
• Membrane... It is a thin moisture-trapping film made from more technologically advanced polymers. These materials have a complex structure with many layers. The membranes have a long service life, they are not afraid of water pressure and ultraviolet radiation.

What is the best waterproofing for a roof under a metal tile to choose if you have a warm type of roof? It must be a material with vapor-permeable properties. In this case, it must be laid in such a way that a ventilation gap remains between the roofing material and the insulation.

How to properly install waterproofing under metal tiles

When deciding which waterproofing to choose for a metal roofing is best in one case or another, it should be borne in mind that its laying begins after assembling and installing the rafter system, but before laying the roofing material. Let's see how it is done, in what sequence.

The moisture-repellent material is laid using the following technology:

1. The material is cut into strips, while their length should be equal to the length of the ramp plus 10-15 percent.
2. The waterproofing is laid with sagging so that during the leakage the water pressure does not cause the material to burst.
3. The waterproofing strips are laid at right angles to the roof rafters with an overlap of 10-15 cm.
4. The membrane or film is attached along the entire length of the rafters using a construction stapler.
5. Fastening of roofing material to the rafters should be carried out using galvanized nails.
6. The joints of the strips can be glued with a moisture-repellent sealant, construction tape, or you can leave everything unchanged.
7. After fixing the moisture-repellent material along the entire length of the rafters, a counter-lattice is installed, which forms a ventilation gap.

Above, we have analyzed in detail which membrane to choose for metal tiles. Keep in mind that without a well-designed waterproofing, the service life of a metal roofed roof will be significantly reduced. This simple and at the same time inexpensive material will make it possible to extend the service life of insulation, roofing material and the entire roof. As a result, the roof will last as long as possible, and you will not need to spend money on repairs again and again.