Diffusion membranes for roof waterproofing. Waterproofing film for roofing, selection and installation: selection rules and price of waterproofing film

You will be interested to know that in Russia, in private housing construction, until the middle of the twentieth century, waterproofing materials were not used at all, or roofing material was a rare exception. And given that the foundations at that time were also built without waterproofing, it is surprising how some houses still stand? Later, glassine and its analogues came into play, which also did not do its job very well.

And now, from abroad, high-quality waterproofing materials began to be supplied, which immediately launched similar production on the spot. Therefore, modern waterproofing film for roofing is already far from its unpretentious predecessors.

Today it is a whole scientific achievement, which helps to keep the under-roof space from even the slightest drop of rainwater. Moreover: the right film is up to 50% guarantee of durable and trouble-free operation of the roofing "pie". And what are the types of such films, and how to fix them - we will now tell you in detail.

Let's immediately note the differences between the two roofing materials: waterproofing membrane and waterproofing film. Many believe that they differ in such parameters as vapor permeability, layering and price.

Yes, and manufacturers are also trying to convince everyone for marketing purposes that films are the past, and membranes are a completely new material, although they do not draw any clear boundaries between these two materials.

This is partly true, but in fact, if we turn to the world encyclopedia of knowledge, we will find out that the membrane is "a thin flexible film, usually fixed around the perimeter." Therefore, it is more correct to consider the membrane as new, more modern look films.

And the principle of operation for both films and membranes is practically the same - to protect the under-roof space from dampness and leaks:

Also, the installation of conventional and modern films remains similar to this day:

How to choose a film for roof waterproofing?

Let's now take a closer look at what assortment the modern market offers today, and what materials are popular with roofers. Moreover, there are a lot of types of modern roofing films, depending on what exactly you want to get in the final.

UV resistance

Have you ever noticed how fragile the film becomes, and what tatters it can turn into after being outdoors for just one summer? Especially if you bought the cheapest one on the market and just covered the bricks with it, for example.

And how much fresher can look almost the same, at first glance, greenhouse cover, although it has withstood the same number of sunny days. It's not about the thickness - it's about such a parameter of the film as resistance to ultraviolet rays.

Resistance to ultraviolet radiation only at first glance seems to be an insignificant parameter for a roofing film - after all, it will be hidden under the facing material! Yes, this is true, only many people forget about force majeure circumstances. For example, you bought a waterproofing film with low UV resistance and plan to spread and cover it in one to two days.

The team is in place, the film is quickly “stapled” along the crate, and only a simple installation of the roof remains. And then - unexpectedly - rain, thunderstorms, lack of material, loss of fasteners, power outages and much more. A few days of such downtime on hot days can reduce the strength of such a film by 50%! Now calculate how much its final durability will decrease accordingly.

So is it worth the risk? Believe me, completely removing all waterproofing, going for a new one and re-carrying out all the installation work is not a pleasant thing, especially pulling out pieces of an old (unexpectedly outdated) film from under metal brackets.

You will be surprised, but even quite expensive branded waterproofing films can have a very low UV resistance. It's just that they are intended for internal installation work, and not for roofing, which, unfortunately, not every seller will tell you about.

Life time

The second important requirement for a waterproofing film is durability. You don’t want to completely dismantle the roof every 5 years to re-lay the waterproofing, do you?

Therefore, most manufacturers add special components to the composition of such a film that enhance strength and wear resistance. Such, for example, are modern reinforced films for waterproofing roofs:

Water pressure strength

There is also such a characteristic of a waterproofing film as the ability to withstand the pressure of a water column. This is its quality, which allows for a long time to keep under the pressure of water and not let it inside.

Do you experience heavy or prolonged rainfall in your area? Then pay attention to this option. Or is your roofing material so arranged that snow flies under it and melts there, like a metal tile?

Those films that are mounted without joints, immediately with a whole roll, do well with such films:

For example, the most best option waterproofing for such roofs - a three-layer subroofing film with a load-bearing reinforced grating and lamination on both sides. This is an excellent water vapor barrier.

Base adhesion

There are two types of waterproofing film: welded or mechanically laid.

The deposited polymer film has a multilayer structure. The bottom layer is a thin film that melts easily at elevated temperatures. Such waterproofing is especially convenient for roofs. complex design, but close attention must be paid to the tightness of all its joints.

In the second case, the film is attached in the usual mechanical way - with staples or nails. This can be mounted on any base - concrete, wood or profiled sheet, it is only desirable that it be as even as possible.

Anticondensate

The so-called anti-condensation films are also good for roofing, which must be laid with two ventilated gaps. This is an almost indispensable waterproofing if the roofing material is metal, from which something always drips.

Anti-condensation films are distinguished by the fact that they contain a special moisture-absorbing material that retains a large number of moisture. Such a film is denser in thickness and has a roughness.

Non-flammable, durable and resistant to ultraviolet rays, however, has a low vapor permeability. If you like this option, then consider ventilation.

And the installation of such a film is no different from the usual:

Price and quality

Be wary of the cheapest films on the market. The fact is that those are almost always made from polypropylene wound on coils, and as a result, the roof then has no waterproofing or wind protection.

The advantages of more expensive and modern films are that such waterproofing not only protects the under-roof space from moisture getting inside, but also helps to evaporate it. About this - now in more detail.

And further. There is a common belief that the roofing film is easily torn already during the installation of roofing sheets, and in the future it requires replacement almost every year. Which is quite troublesome, of course.

In fact, the film is really not capable of serving as a separate coating due to its fragility (leave it for the winter - only rags will remain by spring), but as an important part of the entire roofing pie, it copes with its tasks 100%.

And even small breaks in the film from fastening with brackets are not really critical - this moisture will easily evaporate at the very first rays of the sun. Remember that it is always noticeably hotter on the roof than below.

Vapor permeability

And finally, one of the most important parameters of waterproofing films. The first thing you need to figure out is your roof will be "cold" or "warm". Those. insulated or not, which directly depends on whether you place a residential attic under the roof or leave a simple attic.

And do not rush to immediately choose the path of least resistance, leaving this area uninhabited - the fact is that over time, rooms “end” in any spacious house, and you want to equip at least some closet for the same billiard room, Personal Area or workshop. Therefore, if your budget allows, immediately do everything to the maximum.

And, if the attic of your house is likely to be insulated, then a simple vapor barrier film for such a roof can no longer be used: firstly, it is not suitable for these purposes and will not last long, and secondly, there will be problems with the insulation itself.

The fact is that a standard waterproofing film has two-circuit ventilation: between the roofing and waterproofing, and between the insulation and waterproofing. With the help of this material, the so-called "cold" roof is arranged.

But for a “warm” device, the moment is important that the steam from the insulation comes out, and the waterproofing film does not interfere with it:

Of course, modern films already have this property more:

What does the modern market offer?

And it offers many options. Therefore, let's first of all learn to understand the markings and take a closer look at some of the most popular brands.

Marking

So, the AM marking denotes a film, which is a breathable membrane.

Films A and AM are designed primarily to pass steam well.

But films of class A and B are real blotting papers from a notebook, the main task of which is to absorb and then quickly weather moisture. And they do a really good job with their work, if only the ventilation gap is thought out and equipped.

Brands

So, firm Yutafol. These are high-quality waterproofing and vapor barrier films, accessories for installation and a guarantee. Such films are made of durable polymers:

Waterproofing vapor-permeable membranes Tyvek. This material can be called "smart": it removes excess steam, prevents moisture from entering the under-roof space and lasts a long time.

Tyvek membranes have been in production for decades. Their main advantage is the possibility of laying directly on the insulation, without an air gap. Thanks to this, you can refuse the crate and save a lot on it.

The Delta membrane is used for waterproofing under roofing, and is especially invaluable for roofing made of piece materials and metal rebate. It can be safely used on roofs with a very small angle of inclination - 10 ° less than recommended.

And among domestic films Izospan are especially popular:

How to properly install waterproofing film?

Let's start with the construction of the crate. When installing rafters, do not allow the distance between them to be more than 1.2 m. The optimal distance between the waterproofing film and the roof insulation is 40-60 mm.

Remember: you can work with a waterproofing film on the roof only in dry weather, as soon as the rafter system is fully installed and insulation is laid, if any, is planned.

We spread the film

Laying a waterproofing film has its own technology: from the eaves to the ridge, overlapping, and only this way. Mounting the film is simple: we do it in such a way that rainwater always went beyond the roof. It is only important to prevent water from flowing into the roof space. And the lower edge of the film ensures the removal of dripping drops into the gutter.

Unlike dense membranes, the usual waterproofing film should be spread along the roofing cornice so that it sags between the rafters by 1-2 cm. Such sagging is also necessary so that condensate does not collect on the rafter system:

But the anti-condensate film is spread on the rafters down with an absorbent surface. Secure it with either a construction stapler or special galvanized wide-head nails. Make sure that its lower surface does not come into contact with the insulation anywhere.

We make the right overlap

The overlap of the waterproofing film is made different, depending on the slope of the roof:

With a slope of less than 30 °, the overlap should be within 15-20 cm.
With a slope of 12-30 °, an overlap of 25 cm is required.
If you are waterproofing pitched pitched roofs, increase the overlap on the ridges by another 5 cm.

We fix with slats

And after you have spread the waterproofing film, fix it additionally with 3x5 cm slats, nailing them over the rafters with the same galvanized nails. And on top there is already a crate, which has its own parameters for each roofing material.

We seal the joints

For all film waterproofing materials, the rule is the same: all joints of waterproofing materials must fall on the rafters. But adhesive materials for different types use their own.

For example, ordinary films are simply glued with adhesive tape, and additionally sealed with a dispersion.

Installation technology of modern membranes

If your roof has a relatively low slope or a long valley, we recommend that you put two layers of membrane.

Modern volumetric membranes must be laid strictly parallel to the cornice overhang. Each next roll should overlap the attachment points by at least 7 cm, and glue the overlap area with special glue.

Apply the membrane around the chimney 5-10 cm above the future roofing. Be sure to seal the cuts at the corners.

To seal modern membranes, whole sets of adhesives are used. Although some of these films already have sticky edges that do not require tape.

Apply the membrane to the valley sheets with the same overlap, and fasten with staples or nails. Glue all overlaps in the valley.

If you get in the way of skylights, bypass them in the same way as pipes, taking into account the recommendations of their manufacturers. Basically the rules are: when working with a roof window, apply the membrane to the window frame 5 cm wide. Fasten and seal all connections, as in the picture. By the way, special seals are often provided for such windows.

How to check the reliability of waterproofing?

OK it's all over Now! You can check how correctly your roof waterproofing is done in the end, according to the following three points:

Point 1. Waterproofing is laid under all roofing elements, cornices and gable overhangs.
Point 2. The bottom sheet of waterproofing is out of bounds eaves plank- to the frontal board or to the drainage system.
Point 3. The waterproofing film adheres securely to the walls and pipes on the roof.

Everything is just like that? Congratulations! You will not have problems with roofing waterproofing, and this is already half the battle!

The construction of the roof is a crucial moment, from which the entire structure of the house consists. Therefore, roof waterproofing is one of the necessary goals during roof construction. Properly carried out roofing waterproofing will provide the roof structure with the necessary parameters, as well as increase the operational life of the structure.

Roof waterproofing will protect the roof from rain and condensation. We will answer the questions: what materials are used and why is roof waterproofing needed? What waterproofing is best?

Today, the construction market provides a huge selection of materials for roof waterproofing. All materials are divided into:

film;
membranes that "breathe";
hydrophilic rubber that perfectly absorbs water;
synthetic polymers containing urea fragments in the main chain (polyurea);
silicate resins;
acrylate compositions, consisting of two components.

Let's consider each in more detail.

Membranes and films

Which film or membrane to choose for the roof of your house? These materials are also divided into:

Diffusion - this type is suitable for a roof with absolutely any design. Thanks to the micropores that are in the membrane or films, drops of moisture are absorbed. After that, moisture droplets evaporate with the help of a ventilation gap. Diffusion membranes are fire resistant. They are also environmentally friendly material that does not cause any harm to the human body. The membranes have long term operation, and they also differ in the effectiveness of protection against rain and other precipitation.
Superdiffusion. This type differs from diffusion membranes in that they do not have a ventilation gap. Thanks to this membrane, the structure remains dry. Thanks to superdiffusion membranes, heat is practically not lost, and steam is also perfectly passed through. This film has a high level of UV resistance. This type membranes are applied when it will be covered with a metal tile.
- PVC films - a membrane, at the base of which is polyvinyl chloride. The material is flexible, as it contains plasticizers. This material has several advantages:
- The PVC membrane has a high level of resistance to various types of exposure (chemical, mechanical, and so on).
- The material is elastic.
- Excellent maintainability. Waterproofing can be repaired.
- Huge service life.
- This type of film is an environmentally friendly material.
Film EPDM membranes. The composition of this material is synthetic rubber with polymers. This material is great for roofing houses in areas where poor climatic conditions. Several advantages:
- The original characteristics of EPDM film membranes are retained even at very low temperatures.
- Excellent physical and mechanical parameters.
- Installation is carried out in a short period of time and is easy. It can be quickly performed on any roof structure.
- The material is completely waterproof.
- There is a high level of resistance to various climatic precipitation.

These are the most common types of membranes or films that are used during roof waterproofing. One roll is enough for 20 m2.

Liquid waterproofing

Today, liquid rubber has become widespread. This material is applied to the surface using airless spraying. If you are using liquid rubber to apply a waterproofing layer, then two workers will be enough for this procedure. But for installation work, you will need specially designed equipment. Roof waterproofing with liquid rubber is a great option.

This material has the following advantages:

Effectiveness. The roof will have perfect water protection.
No seams. After applying this material to the surface, no seams are formed. Due to this property of liquid rubber, a continuous monolithic coating is formed.
Excellent adhesion to absolutely any surface (adhesion). This factor does not even depend on the age of the old coating.
Liquid rubber is perfect for a roof with absolutely any configuration (waterproofing flat roof and roof waterproofing). Thanks to airless spraying, liquid rubber can cover every corner of the roof.
The material perfectly tolerates strong changes in air temperature.
There is a high level of UV resistance.
Liquid rubber does not contain toxic substances. Liquid rubber will not harm your health.
Installation on the application of liquid rubber on the roof surface can be carried out even at low temperatures.

These are the main advantages of liquid rubber, but not all. Consider the following material.

Waterproofing film or vapor barrier

Using a waterproofing film (or hydro-barrier film) is the easiest way to waterproof a roof. It creates a hydro-barrier and a vapor barrier. What is a vapor barrier? A vapor barrier is a roofing film that is installed to protect against vapors.

This material is best suited for pitched roof, which is made of metal tiles or slate, as well as for roofing under corrugated board. Waterproofing under corrugated board is also carried out using this material. The main functions of the waterproofing film:

The waterproofing material has good protection against condensate that forms from the inside of the roof.
prevents the penetration of moisture into the insulating material. Moisture degrades the performance of the insulation.
These waterproofing materials for roofing remove steam to the open air (vapor barrier film).
Roof waterproofing is underway.
Waterproofing can be repaired.

If you are performing waterproofing using a film, then some nuances must be observed. If the slope of the roof is more than thirty degrees, then the waterproofing film is overlapped by twenty centimeters. Do not stretch the waterproofing film.

Penetrating waterproofing

Penetrating waterproofing is used for roofs that have a porous structure. Concrete has a porous structure. The principle of penetrating waterproofing is that the material fills all cracks and crevices, including small ones. After the material penetrates into the cracks, it hardens, creating a durable coating.

Most often penetrating waterproofing is liquid glass. Liquid glass is a solution that consists of sodium silicates. Liquid glass does not contain toxic substances. This material protects the coating not only from moisture, but additionally from corrosion and alkaline environment. Bitumen can be used as a penetrating waterproofing, but this is done extremely rarely.

2.5 kilograms of the mixture is consumed per square meter. This is quite a lot for 1 m2.

Gluing waterproofing

This method of waterproofing is known. Roll roofing and waterproofing materials (or sheet) are used here:

ruberoid;
only;
glassine;
ecoflex;
vinyl plastic

There are other materials of roll or sheet type.

Installation in this case is complicated. Before installing roll or sheet material, a bituminous mixture is applied to the surface. Next, the roll or sheet is installed on the roof surface with an overlap. The installed material is then glued. In the end, the coating must be sprinkled with stone chips.

In addition to all the listed materials that are used for roof waterproofing, other materials are also used, for example, emulsions, polymer varnishes. They have great features. They must be applied in several layers to increase the strength of the surface. At the end, they must be sprinkled with sand, which is fine-grained.

Step by step instructions for roof waterproofing

First, let's see what a roof waterproofing device should look like:

Installation work on waterproofing the roof requires care and accuracy from the worker. You also need to have some experience and knowledge in order to do the installation yourself.

Installation begins with the installation of rafters. The waterproofing and roofing material in this case is rolled waterproofing for the roof (roofing membrane). Therefore, consider step by step instructions using membrane material. Consider the following algorithm of actions:

The roll is installed across the rafters. smooth side should stay at the top.
From one end, the material is fixed with a construction stapler. Then there is tension and fixation along the entire length of the roll hydro insulating material.
Then you need to cut off the edge of the membrane.
Next is the installation of the counter-lattice. Thanks to the counter grille, a ventilation system is provided.
After that, the covering is stuffed from the battens (battens).
Similar procedures are carried out around the entire perimeter of the roof. The membrane is installed with an overlap (one hundred millimeters).
Joints must be sealed with adhesive tape (roof sealing).

That's the whole process of waterproofing the roof.

Roof waterproofing with liquid rubber

What is the technology for applying liquid rubber? What to do to get a "liquid roof". If you are using liquid rubber for roof waterproofing, you must first carefully prepare the surface. The preparation of the surface includes the dismantling of the old coating, cleaning from dirt and dust. After the surface must be primed and apply liquid rubber. A "liquid roof" is formed.

The quality and the desired result depends on the correct waterproofing. Therefore, for independent work you need to follow some rules and nuances:

Areas where joints are formed must be carefully repaired.
Installation work on applying a waterproofing layer should begin at the place where the drainage system is located.
If several layers of waterproofing material are being laid, then one rule must be observed. The offset between the top and bottom material should be fifty centimeters.
The waterproofing membrane must be fastened with a construction stapler. This is the most the best way mounts.
Use diffusion films for metal roofing.
If a specific roll material is used as waterproofing, then installation should be carried out at a time when the temperature is not lower than ten degrees Celsius.
If liquid rubber is used, then it must be sprayed in uniform stripes. The width of such strips should be one and a half meters.
If the roof has a complex configuration, then the waterproofing membrane must be glued.

It is necessary to carefully listen to these advices of professionals, because the final result depends on it.

Outcome

Let's summarize. If you correctly and efficiently carry out waterproofing of the roof, then completely protect this part of the house structure from leakage. To do this, you need to do the work carefully, because it is painstaking.

For installation work, you need to have certain knowledge and experience. Do not forget that the roof is one of the main parts of the house, on which the overall comfort and coziness depends. Therefore, the waterproofing of this part of the room must be approached responsibly.

Do not save on the purchase of quality materials, because they have a higher cost in the construction market. Choose the material that can be repaired waterproofing. Used for repair gas-burner. It is necessary to immediately calculate: what will be the consumption of propane.

There is reinforced waterproofing. Reinforced waterproofing is used most often as an additional protection. During installation, a reinforcing mesh is used.

Roof protection from moisture - important aspect, which must be taken into account when arranging the roof. For this purpose, various types of waterproofing membranes are used.

What is a roof waterproofing membrane

When building a house, it is important to use not only high-quality materials, but also protective layers that prevent deformation of the load-bearing elements of the building. The waterproofing membrane is one of the important elements roofing coatings.

Its main function is to protect truss system roofs from moisture and precipitation. This prevents rotting wooden rafters, the appearance of cracks in concrete slabs and other unpleasant consequences.

The waterproofing membrane is an obligatory part of the roofing pie, designed to remove moisture from the under-roof space to the drainage system.

Often membranes are confused with waterproofing films for roofing. When choosing a material, it is worth considering that the membrane is an improved version of the film and has better technical characteristics than film sheets.

Characteristics and properties

Membrane materials for roof waterproofing are diverse, but have common features. Their important advantage is that they are saturated with flame retardants and enhance the fire protection of the roof. A high degree of elasticity makes it easy to lay membranes on any surface. This is ensured by the presence of plasticizers, stabilizers and other fillers in the composition.

Waterproofing membranes are laid immediately before installation of the roofing material

Many characteristics of waterproofing membranes differ depending on their type, but a number of important qualities are present in all such products:

light shade of the canvas to prevent heating of the membrane;
frost resistance and the ability to operate at temperatures below -18 ° C;
resistance to mechanical stress and stress;
service life of about 30 years, depending on the type of material.

Types of membranes

The basis for the manufacture of waterproofing sheets are different structures, and therefore there are several types of membranes. Material characteristics, installation features and other parameters differ significantly.

Membranes vary in appearance, characteristics and installation methods

When choosing a particular option for waterproofing for a roof, it is worth considering the task that the material must perform. Moisture protection is the main function, but installation features, cost and other parameters should also be taken into account. Therefore, you first need to study the main types of waterproofing membranes:

PVC sheets, which are based on plasticized polyvinyl chloride film. The material is reinforced with polyester mesh and therefore withstands stretching up to 200%. The technical characteristics of the membrane are maintained at an operating temperature of -40 to +60 °C. PVC sheets are supplied in rolls with different widths and lengths;
PVC membrane is dense and tear resistant
EPMD membranes are made from synthetic polymerized rubber, stabilizing additives and reinforcing mesh. The service life is from 50 years, while the coating is environmentally friendly and harmless to human health and condition environment. Stretching can reach 400%, but the structure is also resistant to higher loads;
Synthetic membranes based on polymerized rubber are highly elastic and environmentally friendly
TPO structures are made from thermoplastic type olefins, which are based on rubber and polypropylene. The material has a very high resistance to abrasion and mechanical stress, therefore it is durable - its service life is more than 50 years. Compared to other membranes, TPO sheets have less elasticity, but are compatible with any roofing materials based on bitumen and polystyrene;
TPO sheets have a very high resistance to mechanical stress, therefore they serve more than 50 years
profiled membranes for roof waterproofing are made from high-strength polyethylene and have a surface with many protrusions. The canvas can consist of three layers of film. The material is suitable for waterproofing roofs and other building elements.
Profiled sheets are used for waterproofing any building elements, including the roof.

How to choose a roof waterproofing membrane

The range of waterproofing materials includes various options with different characteristics, appearance, quality level and other parameters. Therefore, before choosing, you need to determine the key factors that are taken into account when determining suitable option material. When choosing a waterproofing membrane, you should pay attention to the following parameters:

On the market building materials products of several manufacturers stand out in particular. Products of such brands are in demand as:

Jutafol - manufacturer of a wide range of materials for hydro and vapor barriers for roofs different type. Membrane films in the Utafol assortment are distinguished by their compliance with current quality standards, as well as durability, strength and resistance to temperature extremes;
Waterproofing membranes "Yutafol" are especially in demand and are durable
Tyvek. The company specializes in the manufacture of roofing materials, and membranes occupy one of the main positions in the brand's assortment. Vapor and waterproofing membranes withstand operation at low temperatures, contribute to the removal of steam to the outside and prevent the penetration of moisture inside the room;
Modern waterproofing membranes manufactured by Tyvek are highly moisture resistant and elastic
"Technonikol". A well-known domestic manufacturer of building materials produces goods focused on Russian climatic zones. Waterproofing films and membranes are suitable for regions with harsh winters and high humidity, as they are resistant to ultraviolet radiation, aggressive substances and high tension.
TechnoNIKOL profile membranes are designed for use in conditions of low temperatures and high humidity

Preparation and installation rules

The installation of the membrane is simple technology, but to achieve a good result, it is important to consider the following simple rules preparation:

the distance between the rafters should not be more than 1.2 m;
the gap between the waterproofing and the roof insulation should be from 40 mm;
all work must be carried out only in dry weather;
films or membranes need to be spread from the eaves to the ridge, overlapping about 15 cm;
the fabric should not be stretched too much. The optimum sagging depth is about 20 mm.

The amount of overlap is determined depending on the angle of the roof:

if the slope is 30 °, then the canvases are laid on top of each other by 15–20 cm;
at an inclination of 12–30 °, the overlap is made equal to 25 cm;
for steep four-pitched roofs on the ridges, the overlap is increased to 30 cm.

Membrane sheets are laid with an overlap, the value of which depends on the angle of inclination of the roof

Installation steps

The method of installation of waterproofing films varies depending on the type of material. Self-adhesive sheets do not require mechanical fasteners, as they are fixed to flat surfaces by heating. Profile membranes, on the contrary, do not have an adhesive base, therefore they are fixed with nails or staples. The installation sequence of the profile membrane is as follows:

The roll is rolled out on the surface of the roof and strips of the desired length are cut off.
At the joints of roof slopes and the passage of chimneys and ventilation pipes, the film is carefully cut, and the edges are fixed with adhesive tape

Video: installation of membranes on the roof

Waterproofing membranes are necessary to protect the load-bearing elements of the roof from precipitation, which ultimately ensures the durability of the entire structure. To achieve this effect, it is important to choose the right material and perform installation in accordance with the recommended technology.

What are waterproofing membranes, production technology, scope, how to choose a membrane

Article prepared with input from Tyvek® experts

Modern roofs are a complex system in which both the reliability and durability of the structure as a whole depend on each layer. And if the decorative effect of the “fifth facade” is largely determined by the type of roofing, and the reliability is determined by the compliance of the rafter system with the expected loads, then under-roofing waterproofing is responsible for the tightness and safety of the insulation and rafters, and, consequently, for the service life of the roof. Nevertheless, for some, the need for its use is still in doubt, and even with the choice there are often difficulties. Finally, the experts of DuPont, the manufacturer of Tyvek® building membranes, will help to dispel doubts about the appropriateness of using the material, together with which we will consider the main aspects related to roofing waterproofing.

Why Do You Need a Waterproofing Membrane?
Raw material base and production technology.
Features of the choice of membranes in questions and answers.

Functions of the waterproofing membrane

Membranes are called vapor-permeable, but moisture-impervious "breathing" films - they protect structures from moisture penetration, but freely pass steam. It is vapor permeability, that is, diffusion, of membranes that distinguishes them from impermeable waterproofing (anti-condensate) films.

Although a vapor barrier is used when constructing roofs, it is unrealistic to completely prevent the entry of vapors into the insulation, and a certain amount penetrates into it one way or another, but it is brought out through the diffusion membrane and does not settle on the surface in the form of condensate. Also, moisture enters the under-roof space as from the atmosphere, through leaky areas in the finish roofing, and is formed in the form of condensate due to the temperature difference. But, regardless of the source of moisture, its presence in the roofing "pie" is fraught with a number of problems:

humidification of the insulation - with an increase in humidity at thermal insulation materials the characteristics of thermal resistance deteriorate significantly;
moistening the wooden elements of the truss system - the appearance of mold, fungus, rotting, loss of strength, shortening of service life.

In addition, the membrane protects the insulation from the wind, preventing convective heat transfer (convective heat loss). As a waterproofing and wind protection membranes are used in pitched and sloping metal roofs, mainly in low-rise and private construction.

The main characteristics of high-quality membranes include high vapor permeability, strength, water resistance, wide temperature range, and resistance to ultraviolet radiation.

Vapor permeability - from 600 g / m² in 24 hours (Sd Lover of Apples Member of FORUMHOUSE

Tell me which films to use for the pie of the insulated residential attic. On the rafters 50x200 mm with a pitch of 630 mm, the waterproofing membrane overlaps from above, glue the joints. On it, along the rafters, there is a counter-lattice of a bar 50x50 mm, on it a crate with a step of 25 cm, a board 25x100 mm or 25x150 mm (along the wavelength of the MCH 35 cm). Inside the rafters are stone wool, vapor barrier, lining. It seems to have heard that there should be a gap between the waterproofing and the insulation, but I do not provide for it. This is bad? The gap will be along the counter-lattice and the exit through the ridge.

When used as waterproofing impervious (convective) films, to remove condensate from the surface of the insulation, their installation is carried out with an additional ventilation gap. But modern concepts of energy-efficient construction provide for the creation of a sealed thermal circuit, and this is possible when waterproofing is installed directly on the insulation. You did everything right, the ventilation gap between the insulation and the wind-water protection of the diffusion-open film is not needed.

Raw material base, production technology, features

The diffusion membrane market is represented by several varieties, the differences in the characteristics of which are due to both the raw material base and the production technology.

Microperforated membranes - made from non-woven polypropylene, vapor permeability is ensured by punctured cone-shaped holes (pores). They are characterized by relatively low diffusion (about 40 g/m² per day), which is why they belong to the type of pseudo-diffusion membranes and are mounted only with a ventilation gap. And according to modern SNiP, microperforated membranes are not allowed to be used as waterproofing, because due to the size of the pores, they are not able to effectively retain water.

Microporous membranes made of polypropylene fibers - permeability is achieved by a large number of interfiber pores. Due to the characteristics of polypropylene and the characteristics of the production cycle, such films are produced in multilayer to protect the working layer (part of the membrane that allows steam to pass through but retains water) from mechanical damage.

Polyethylene membranes high density(HDPE) - are made from the finest continuous fibers by super high speed molding at high temperatures.

High-tech diffusion membranes made of thermoset polyethylene have a unique structure that is stably vapor-permeable and waterproof. For this material, the thickness of the working layer is 6-8 times greater than that of multilayer analogues. This thickness, coupled with high UV resistance, guarantees the membranes longevity and performance over the entire service life, which is about fifty years according to the results of laboratory studies. Also, high-density polyethylene membranes are superior in terms of water resistance, as the following table illustrates.

How to choose the right membrane

So, waterproofing membranes in a roofing pie are needed - we determine the selection criteria. The functionality of the membrane consists of a set of characteristics and the optimal ratio of density, vapor permeability and waterproofing properties.

Also, in addition to vapor permeability and strength, the thickness of the working layer is important.

The thicker the working layer of the membrane, the greater its service life, therefore, it will not be necessary to overhaul the roof in a few years due to leakage, after the thin membrane becomes unusable. In comparison, the thickness of a human hair is about 80 microns, while the working layer thickness of a standard roofing substrate is about 30 microns, and the rest is protective layers.

The specifics of the application are also of great importance - specialized membranes are produced for cold and insulated roofs, and there are also universal ones. If you have not finally decided on the status of the attic or attic, you should not choose specialized waterproofing.

We are installing a roof made of metal tiles, now we plan to leave it cold, but in the future, perhaps, we will insulate it. Question to the experts - what kind of roofing material is better to use, so as not to redo it later?

It is important not only the presence or absence of insulation, but also the slope - some modern technologies assume only sloping roofs.

I'm a little confused as to which film to put where. There is a SIP roof, and on top of it the would-be builders simply put a metal tile, now dripping from the ceiling, most likely, condensate. Could you please explain what to fasten indoors on the panel and what to fasten under the metal tile on the panel?

And this is not the case for a universal membrane.

A vapor barrier film is installed in the room. Under the MP (a specialized wind-water-protective diffusion-open film of increased strength (functional layer thickness 450 microns) is laid on the surface of the OSB).

Also, almost always, when choosing a particular building material, one of the decisive factors is its price. However, do not forget that the roof, like a house, is a capital structure and, subject to technology, including the installation of a membrane, should not require substantial investments for as long as possible. Given that the savings from purchasing budget material in the general mass is unlikely to be significant, quality should be the decisive factor.

A high-quality waterproofing membrane is a dry insulation and rafters, a reliable and durable roof.

When you like how tiles look on the roof, but there is no financial opportunity to use this roofing, you can make an imitation of slate. If the preference is metal, but the metal tile is set on edge, you can try corrugated board. In the video - about the rules for installing a roofing pie and the features of using membranes.

Properties and application features of roof waterproofing membranes

Protecting the roof from moisture is an important aspect that must be taken into account when arranging the roof. For this purpose, various types of waterproofing membranes are used.

What is a roof waterproofing membrane

Its main function is to protect the roof truss system from moisture and precipitation. This prevents rotting of wooden rafters, the appearance of cracks in concrete slabs and other unpleasant consequences.

The waterproofing membrane is an obligatory part of the roofing pie, designed to remove moisture from the under-roof space to the drainage system.

Characteristics and properties

Waterproofing membranes are laid immediately before installation of the roofing material

Many characteristics of waterproofing membranes differ depending on their type, but a number of important qualities are present in all such products:

light shade of the canvas to prevent heating of the membrane;
frost resistance and the ability to operate at temperatures below -18 ° C;
resistance to mechanical stress and stress;
service life of about 30 years, depending on the type of material.

Types of membranes

Membranes vary in appearance, characteristics and installation methods

PVC sheets, which are based on plasticized polyvinyl chloride film. The material is reinforced with polyester mesh and therefore withstands stretching up to 200%. The technical characteristics of the membrane are maintained at an operating temperature of -40 to +60 °C. PVC sheets are supplied in rolls with different widths and lengths;

PVC membrane is dense and tear resistant

Synthetic membranes based on polymerized rubber are highly elastic and environmentally friendly

TPO sheets have a very high resistance to mechanical stress, therefore they serve more than 50 years

Profiled sheets are used for waterproofing any building elements, including the roof.

How to choose a roof waterproofing membrane

The range of waterproofing materials includes various options that differ in characteristics, appearance, quality level and other parameters. Therefore, before choosing, you need to determine the key factors that are taken into account when determining a suitable material option. When choosing a waterproofing membrane, you should pay attention to the following parameters:

composition - the waterproofing film must be impregnated with fire retardants, which increase protection against fire;
service life - the material must perform its functions for at least 30 years;
fastening method - it must be borne in mind that some membranes are designed for fusing installation, which is suitable for flat roofs;
the cost of the material - it should not be too low compared to the average market price, because this may be an indicator of poor quality or marriage.

Different types of films are stacked and fastened in different ways: they are nailed with a stapler, glued with mastic or a special composition, or fused with a gas burner

In the building materials market, the products of several manufacturers stand out in particular. Products of such brands are in demand as:

Jutafol is a manufacturer of a wide range of materials for hydro and vapor barriers of various types of roofs. Membrane films in the Utafol assortment are distinguished by their compliance with current quality standards, as well as durability, strength and resistance to temperature extremes;

Waterproofing membranes "Yutafol" are especially in demand and are durable

Modern waterproofing membranes manufactured by Tyvek are highly moisture resistant and elastic

TechnoNIKOL profile membranes are designed for use in conditions of low temperatures and high humidity

Preparation and installation rules

Mounting the membrane is simple technology, but to achieve a good result, it is important to consider the following simple preparation rules:

the distance between the rafters should not be more than 1.2 m;
the gap between the waterproofing and the roof insulation should be from 40 mm;
all work must be carried out only in dry weather;
films or membranes need to be spread from the eaves to the ridge, overlapping about 15 cm;
the fabric should not be stretched too much. The optimum sagging depth is about 20 mm.

The amount of overlap is determined depending on the angle of the roof:

if the slope is 30 °, then the canvases are laid on top of each other by 15–20 cm;
at an inclination of 12–30 °, the overlap is made equal to 25 cm;
for steep four-pitched roofs on the ridges, the overlap is increased to 30 cm.

Membrane sheets are laid with an overlap, the value of which depends on the angle of inclination of the roof

Installation steps

The roll is rolled out on the surface of the roof and strips of the desired length are cut off.

The rolls are spread on the roof, taking into account the overlap and the canvases of the required length are cut off.

On top of the waterproofing, a crate for roofing material is mounted

At the joints of roof slopes and the passage of chimneys and ventilation pipes, the film is carefully cut, and the edges are fixed with adhesive tape

Video: installation of membranes on the roof

Materials for waterproofing pitched roofs

The waterproofing of a pitched roof prevents the negative impact of high humidity on the condition and physical characteristics of the truss system and other materials that make up the subroof structure.

An increase in humidity is caused by precipitation and condensate formed from water vapor coming from residential or technical premises.

The choice of waterproofing material for a particular roof structure should be made based on the type of other underlay materials: sound and heat insulating, vapor-tight, etc. Only the correct combination of all elements of the roofing pie will make it possible to build such a roof that would satisfy all the requirements of the owner of the house.

deposit photos

Diffusion membranes

This type of waterproofing provides, in addition to the main function (preventing the penetration of moisture into the heat insulator), the possibility of removing water vapor formed in the premises of the house. Vapor permeability is achieved by a special technology for the production of non-woven fabric from synthetic polymer fibers.

Diffusion membranes also contribute to the preservation of the internal thermal energy of the house. This possibility is achieved by the anti-wind properties of the material: heat is not blown out of the under-roof space by cold air flows. For greater efficiency, multilayer membranes (up to 4 layers) can be used.

During installation, diffusion membranes are laid directly on the surface of the insulation - no ventilation gap is required between them. This achieves the optimal distribution of space between the rafters during the installation of thermal insulation materials.

A ventilation gap must be provided above the membrane. The junction of adjacent membranes must have an overlap of at least 10 cm and, for tightness, be glued with adhesive tape that is resistant to low temperature and humidity.

One of the parameters of diffusion membranes is vapor permeability, which is the ratio of the amount of water vapor (in grams) to the area of the material (in square meters) through which a given amount of water vapor passes in 1 hour. The lower the vapor permeability, the better the membrane performs its functions.

DELTA membranes (Dorken, Germany)

TYVEK membranes (Dupont, France)

Membranes Yutavek (JUTA, Czech Republic)

Membranes Izospan (Geksa, Russia)

Waterproofing films

Conventional waterproofing films require two ventilation gaps on both sides during installation. This requirement is due to the low vapor permeability in addition to high moisture resistance. The gap between the film and the heat insulator is designed to remove condensate from the roofing cake.

It is advisable to use waterproofing films for the construction of cold attics and mansards.

An important characteristic of a waterproofing film is water resistance, measured in millimeters of water column. Higher water resistance provides better waterproofing properties.

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waterproofing membrane

A waterproofing membrane is a material that is used to protect a building from moisture, condensation and precipitation.

The waterproofing membrane protects roofs, floors, walls and other parts of the house from the negative effects of moisture. Without a waterproofing membrane, the insulation will quickly get wet and lose its heat-insulating properties. This will directly affect the temperature in the house and heating costs.

In the article we will talk about the features of the waterproofing membrane, its types, the basic rules for choosing and laying.

How a waterproofing membrane works

Often people confuse waterproofing membranes and vapor barrier films. Despite their similarity (production material, thickness, density), they have one fundamental difference. Namely, the principle of action.

The vapor barrier film protects the insulation from the internal moisture of the house. This is especially true in rooms with high humidity. For example, in the bathroom.

The vapor barrier film does not allow steam and moisture to pass through. Waterproofing is another matter. In addition to moisture and windproof properties, it has vapor permeability. This is necessary to remove moisture, which still seeped into the insulation. The membrane has microscopic pores that allow water molecules to pass through.

Characteristics of waterproofing membranes

The waterproofing membrane belongs to a large group of polymeric insulating materials. The membrane is strong enough, not afraid of temperature changes, flexible and easy to use.

The main properties of waterproofing membranes:

elasticity;
strength;
good weather resistance;
not afraid of temperature changes;
durability.

Where are waterproofing membranes used?

Membranes are used in the following areas:

Types of waterproofing membranes

Waterproofing membranes are of the following types:

Diffusion membrane

It has a more complex structure than conventional film. The pores of the membrane resemble microscopic funnels. Due to this property, it does not allow steam to pass from the outside, but perfectly removes moisture from the inside.

When installing such a film, the narrow part of the pores is laid out to the roof, and the wide part - to the insulation. Requires a ventilation gap on both sides of the membrane.

Super diffusion membrane

According to the principle of operation, it is similar to a diffusion membrane. The main difference lies in the speed of moisture removal - superdiffusion film does it much faster. As a result, ventilation gaps are not needed.

Anti-condensation membrane

Some types of roofing (for example, metal tiles) are very sensitive to condensation on the inside. To solve this problem, an anti-condensation membrane is used. It does not let excess moisture out. Instead, the membrane retains water from the back with its tiny villi. Thus, moisture can escape through the air currents of the ventilation gap.

The shape of the membrane is of the following types:

Waterproofing membrane Ondutis D (RV)

Ondutis D (RV) is a gray fabric with a protective layer and an additive of a UV stabilizer, which withstands direct solar radiation for 1.5 months. Can serve as a temporary roof.

The Smart D (RV) base has a self-adhesive tape. This greatly simplifies the installation process. It can also be used as a hydro barrier in basements.

How to choose a membrane

The main function of waterproofing is water protection. Therefore, the most important parameter is water resistance (measured in mm of water column - the higher, the more effectively the membrane retains water). One more important characteristic- breaking load. The higher it is, the stronger the material.

Also, do not forget about the price. Comparing different types membranes, it is best to focus on the cost of 1 square. meters of film. For more information about the features of the choice of waterproofing, read the article: How to choose a waterproofing film.

Proper installation of the waterproofing membrane

The method of installation of waterproofing membranes differs depending on where it fits - on the roof or on the walls. But the general steps for laying waterproofing membranes are as follows:

The waterproofing membrane is always laid on the insulation, which is pre-mounted on the roof and walls.
The membrane is cut into pieces of the required length and spread on the surface.
The membrane is mounted from the bottom up with horizontal panels of the required length.
For fixing on wooden elements, you can use a construction stapler.
Subsequent layers of the membrane are applied with a mandatory overlap of approximately 10 cm.
For reliable protection of joints, a special mounting tape is used.
The next step is fixing the membrane wooden blocks and installation of cladding for walls or roofing materials for the roof.

Installing a waterproofing membrane is a simple process that does not require special skills. Read more in the article "Mounting a waterproofing film" and watch the video clips.

Roof waterproofing - roofing films and membranes

The main task of roof waterproofing is to protect the under-roof space from moisture penetration from the outside. Water causes rotting of wooden roof elements and a decrease in the performance of wet insulation. Let us consider in more detail the tasks that waterproofing measures and their technologies should solve, depending on the materials used.

The feasibility of roof waterproofing

In addition to the direct fall of precipitation under roofing materials, there are other options for the appearance of moisture drops on the elements of the roofing pie:

Due to the difference in temperatures outside and inside the insulated roof, condensation forms on the inner surface of a number of roofing materials. Roof waterproofing protects the insulation from condensation.
The "dew point" can be formed directly in the insulation itself. Therefore, a ventilation circuit is required on the roof, the type of which depends on the material used for waterproofing. There can be two such ventilation circuits - between the roof and waterproofing and between waterproofing and insulation material. With good vapor permeability of the waterproofing material, the gap between it and the insulation is not required.

Properly arranged waterproofing must meet the following requirements:

The hydroprotective layer is located over the entire area of the roof together with the eaves and overhangs of the gables.
The lower sheet of waterproofing is displayed in the drain.
The roofing waterproofing material adheres tightly to the walls and pipes located on the roof.

Before starting waterproofing work, it is necessary to select the material that is optimal for a particular type of roof. General requirements for waterproofing - moisture resistance combined with vapor permeability, resistance to mechanical damage and elevated temperatures, elasticity. Consider modern materials used to protect the roof from moisture and meet the listed requirements - under-roofing films and membranes.

Types of waterproofing films for roofing

For roof waterproofing, perforated films are used, which are laid between the top coating of the roof and the insulation material.

Features of using perforated waterproofing films:

The increased degree of vapor permeability, in comparison with non-perforated specimens, is still insufficient for the full removal of steam from the premises. Therefore, at the slightest damage to such a film, moisture will accumulate in the insulation.
In dry weather, the micro-holes of the films become clogged with dust, due to which the vapor permeability of the material decreases. The polymers used in the production of films are prone to electrification, which causes a rapid accumulation of dust. Colored films are less electrified.
Installation of waterproofing films in residential buildings With warm roof requires the creation of a lower ventilation gap.

Waterproofing films are divided into polyethylene, polypropylene, with an anti-condensate layer. Polyethylene and polypropylene waterproofing materials are divided into reinforced and non-reinforced.

Utafol D films consist of three layers - two outer ones made of polyethylene film and the main one in the form of reinforcing mesh, can be used for all types of roofs

Anti-condensation waterproofing films are usually used for metal roofs, for example, from metal tiles without acrylic coating. On such roofs, there is a high probability of condensation, leading to the occurrence and development of metal corrosion.

The anti-condensation film has no perforation and is not breathable.

This film does not allow steam to pass from the heat-insulating material to the lower surface of the roofing material and settle on it. All steam is absorbed by the textile waterproofing layer. Therefore, the lower ventilation gap between the film and the thermal insulation is mandatory for weathering the settled condensate.

Polymeric membranes - implementation of innovative technologies

Membranes are relatively new materials and their properties resemble natural material- skin. The membranes have a non-woven structure, which has the ability to pass all the steam accumulated inside the room, but prevent the penetration of external moisture into the under-roof space. Such waterproofing can be placed directly on the insulation material without organizing a ventilation gap. Condensation will not form on the thermal insulation.

Membranes are widely used in houses with heated attics, especially with attics. These are the best materials for converting cold attic spaces into heated attics without changing the truss structure.

A large number of names are used for membranes, but several main types can be distinguished by vapor permeability:

Pseudo-diffusion membranes are perforated roofing films. The level of vapor barrier of such materials is insufficient for their laying without a ventilation gap.
Diffusion and superdiffusion membranes can be installed without a ventilation gap.

For slate roofs, you can use both a cheaper film and a superdiffusion membrane. A gap is required between the film and the insulation, so an additional crate will be required. The superdiffusion membrane is laid directly on the heat-insulating material. The total cost of an effective waterproofing device will be approximately equal. But the membrane is a higher quality material.

According to the installation technology, the membranes are divided into the following types:

Single-sided materials are rolled across the rafters with a certain side up.
Membrane waterproofing of double-sided application can be mounted on the crate (for pseudo-diffusion modifications) or directly on the insulation of either side.

One of the ways of laying membrane material on the roof

Main characteristics of diffusion and superdiffusion membranes

General properties of vapor-permeable membrane materials:

Waterproof and vapor permeable, which is not reduced in dusty environments due to the absence of holes.
The membrane for insulation additionally plays a windproof role, preventing heat from escaping to the outside.
Installation of membrane waterproofing directly on the insulation saves under-roofing space and funds for additional lathing.
The membranes are used in combination with roofing materials, the inner side of which is not subject to corrosion - ceramic, bituminous, cement-sand tiles and metal tiles with a polymer base. The membrane allows steam to pass to the inner surface of the roofing and, with a difference in external and external temperatures, condensate forms on it, causing corrosion of the metal.

Properties of separating diffusion membranes

This class of membrane waterproofing occupies a separate niche and is used for metal roofing - steel, aluminum, copper, galvanized steel.

Separating diffusion membranes are optimal for low-pitched roofs, the roofing of which is made of zinc-titanium alloys. Also recommended for complex roofs with domes and towers.

This waterproofing material is a non-woven membrane made of polymeric materials. The structure is a volumetric three-dimensional lattice with a height of 8 mm.

The cost of under-roof waterproofing and vapor barrier protection is up to 5% of the total cost of the roof structure. At the same time, from a competent choice of insulating material and its correct installation the working condition of the roof and the duration of the repair-free period largely depend.

We invite you to discuss the issue of composition selection and roll materials to protect the roof from the penetration of precipitation and the effects of condensate.

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Article prepared with input from Tyvek® experts

Why Do You Need a Waterproofing Membrane?
Raw material base and production technology.
Features of the choice of membranes in questions and answers.

Functions of the waterproofing membrane

Although a vapor barrier is used when constructing roofs, it is unrealistic to completely prevent the entry of vapors into the insulation, and a certain amount penetrates into it one way or another, but it is brought out through the diffusion membrane and does not settle on the surface in the form of condensate. Also, moisture in the under-roof space comes both from the atmosphere, through leaky areas in the finishing roofing, and is formed in the form of condensate due to temperature differences. But, regardless of the source of moisture, its presence in the roofing "pie" is fraught with a number of problems:

humidification of the insulation - with an increase in humidity, thermal insulation materials significantly deteriorate the characteristics of thermal resistance;
moistening the wooden elements of the truss system - the appearance of mold, fungus, rotting, loss of strength, shortening of service life.

The waterproofing membrane prevents the insulation and elements of the roof system from getting wet due to steam, due to atmospheric moisture, and due to the formation of condensate on the roofing.

The main characteristics of high-quality membranes include high vapor permeability, strength, water resistance, wide temperature range, and resistance to ultraviolet radiation.

Vapor permeability - from 600 g / m² in 24 hours (Sd< 0,03 м).
Strength - from 117 N / 5 cm.
Water resistance - from 1 m of water column.
Operating temperature - from -40 to +100⁰С.
Resistance to UV radiation - from 4 months.

In addition to outstanding specifications, one of the advantages of diffusion membranes is simplified installation and significant space savings due to the elimination of the lower ventilation gap.

Apple Lover FORUMHOUSE Member

Dmitry BelozerovDuPont Technician

Raw material base, production technology, features

Diffusion Membrane Market Represented several varieties, the differences in the characteristics of which are due to both the raw material base and the production technology.

High Density Polyethylene (HDPE) membranes are produced from the finest continuous fibers by ultra high speed molding at high temperatures.

Dmitry Belozerov

How to choose the right membrane

First of all, these parameters must meet or exceed the given ones, since the lower limits allowed by the standards are indicated.

Also, in addition to vapor permeability and strength, the thickness of the working layer is important.

Dmitry Belozerov