Waterproof vapor-permeable membrane for roofing. Roof waterproofing film: how to choose and install it correctly. Membrane Selection Criteria

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 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.

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< 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 technical characteristics, 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

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.

Dmitry BelozerovDuPont Technician

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

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.

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.

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

Dmitry Belozerov

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.

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

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.

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). Another important characteristic is the breaking load. The higher it is, the stronger the material.

Also, do not forget about the price. When comparing different types of membranes, it is best to focus on the cost of 1 sq. meters of film. Read more about the features of the choice of waterproofing in the article:

To protect the under-roof space from moisture, a waterproofing film for the roof is used for the construction of modern houses. The article provides information about the purpose, properties and varieties of this material. It also describes the main stages of installation and selection criteria. This information will allow you to choose the right material and avoid unnecessary costs.

Source baucenter.ru

Purpose of roof waterproofing

Moisture can penetrate under any roofing. Atmospheric precipitation finds cracks in the joints of slate and ondulin. Gusts of wind blow drops of water under the tiles. Condensation of vapors emanating from living rooms also significantly increases the moisture content of roofing materials. Even the most modern insulation is not able to protect the room from dampness, cold and other negative factors caused by wetting the coating.

The main purpose of the waterproofing film is to protect roofing materials from excessive moisture. The right choice and professional installation affects the safety of the entire coating, greatly increasing its wear resistance and durability. This is due to the fact that excess moisture can cause rotting of the wooden elements of the truss system, which can lead to the destruction of the finished roof structure.

Summarizing the above, the main functions of the film waterproofing of the roof are determined. They are as follows:

prevention wooden elements of the roof structure from the effects of moisture penetrating under the roofing outside due to atmospheric precipitation;

building impact protection vapor rising from within premises.

Source desktopwallpapers4.me

In the construction market, roll materials for roof waterproofing are presented in a wide range. To determine the best option suitable for a particular structure, it is necessary to clearly know the properties and conditions for the use of membranes.

Properties of waterproofing film

Some homeowners are intimidated by the rather tangible costs that accompany the installation of the material in question. However, the correct choice of film waterproofing can eliminate unnecessary problems arising from premature destruction of the coating. Particular attention is recommended to be paid to meeting the basic material requirements imposed by the conformity to a particular type of roof. When deciding which membrane to choose for a roof, the following qualities must be considered:

material must have moisture resistance- to protect against the effects of precipitation and condensate;

important property is resistance to ultraviolet, protecting the film from destruction by the sun's rays;

waterproofing material for roofing must be able to maintain its intended qualities, regardless of temperature regime;

The waterproofing film must have moisture resistance Source leksholding.ru

coating durability is increased due to increased mechanical strength film tested by tear resistance;

at the expense anti-condensation characteristics material provides protection for the roof structure from the negative effects of vapors rising from residential premises;

elasticity film waterproofing allows you to withstand significant loads caused by the installation and subsequent operation of the roofing.

The proposed list is only a short list of the necessary qualities that a roll material must have to protect the truss system of a building from moisture. Let us consider in more detail some of the properties that characterize the waterproofing film for the roof.

Criterias of choice

When building a house, each owner counts on the durability of the building. Therefore, it is important to pay due attention to the quality of materials, not paying much attention to their cost, so as not to become like a miser, forced, as the saying goes, to pay twice.

By purchasing cheap products, the risk of its rapid failure increases, entailing the need for unplanned repairs. Source doka-realty.net.ru

The waterproofing membrane for roofing has a number of specific characteristics that are recommended to be considered when choosing the right material. Some of them require detailed consideration.

Preservation of original properties under the influence of sunlight

The influence of ultraviolet radiation on many waterproofing films is expressed by the acquisition of increased fragility and brittleness. Therefore, one of the main selection criteria is the stability of the membranes under the influence of the rays of the merciless luminary.

Although in the final version of the finished roof, the membrane waterproofing of the roof is protected from direct sunlight by several layers of other materials, unforeseen situations occur during the installation process. So an unplanned delay in construction could result in the film being left uncovered indefinitely. Ultraviolet in combination with the wind can cause the destruction of the structure of some materials, which negatively affects their protective characteristics. First of all, the strength of the membrane and its resistance to moisture suffer.

Source pravozem.ru

Professional builders recommend choosing a film waterproofing that is resistant to ultraviolet radiation. This parameter is indicated on the packaging provided by the manufacturer. It should be noted that not all expensive membranes are characterized by a similar quality, collapsing in the sun.

Lifetime

When building your own home, the owner has the right to count on its durability. When investing a lot of money in your future home, you should not save on waterproofing. Of course, you can choose a cheap membrane, which will collapse in a few years, thereby rendering the truss system unusable, subject to unplanned repairs. It would be much more expedient to purchase a waterproofing film from a trusted manufacturer with an impeccable reputation gained due to the high quality of the products supplied. Such manufacturers are not afraid to indicate on the packaging the approximate period of trouble-free operation of the rolled material. The absence of this parameter indicates the uncertainty of the manufacturer in the quality of the product, and such an acquisition will be an unreasonable waste of money.

Source www.krovkomp.ru

Anti-condensation characteristics

Laying a metal coating on a roof structure after preliminary insulation causes the formation of a large amount of moisture in the under-roof space. For such cases, it is recommended to choose a membrane waterproofing with an effect that prevents the accumulation of condensate.

This type of film has a special layer made of cellulose. Thanks to it, moisture is absorbed and reliably retained up to certain conditions. These are either an increase in wind strength or an increase in temperature, contributing to the evaporation of condensate. To facilitate the process by fixing the counter-lattice, special gaps are formed that separate the membrane from the roofing, as well as the waterproofing film from the insulation. Such ventilation accelerates the evaporation process.

The positive qualities of anti-condensate films include increased strength and resistance to ultraviolet radiation.

Source bprice.ua

Vapor permeability

This criterion must be taken into account during the capital insulation of the roof or during the construction of the attic with the subsequent planning of living rooms. The mold that has formed in the insulation layer due to accumulated moisture is a sufficient reason for the destruction of the wooden elements of the roof structure. In addition, the condensed liquid significantly reduces the thermal insulation characteristics of the material. Therefore, for such situations, waterproofing, the membrane of which has the property of vapor isolation, is best suited.

The cold roof protects only the roof structure and the attic, which has a separate ventilation system. For such cases, ordinary film waterproofing is sufficient, without special qualities that affect the cost of the material.

On our website you can find the most . In the filters, you can set the desired direction, the presence of gas, water, electricity and other communications.

The waterproofing film has the property of insulating steam. Source stroyday.ru

Types of roofing roll waterproofing

An interesting fact, but quite recently, during the construction of private houses in Russia, protection of the roof from moisture was not given due attention. The experience of using film waterproofing adopted from foreign colleagues is currently very popular with domestic builders, significantly extending the period of trouble-free operation of the roofing system. This is facilitated by an extensive selection of roll material offered by manufacturers.

Many owners of private properties are interested in a film for the roof of a house, which one is better suited to a particular building. Let's take a closer look at the most popular types of products in question.

Source bel-dom-stroy.ru

With the development of the chemical industry, polyethylene has firmly established itself in the domestic market. Many building materials are made on its basis. Roofing waterproofing, the film of which is made on the basis of polyethylene, has several modifications. Among them, the most widespread are the following subspecies:

a membrane made of high-strength polyethylene, which does not have vapor permeability, which prevents the penetration of air and moisture, requiring separate ventilation due to gaps separating it from the outer layer of the coating and internal insulation using a counter-lattice;

microscopic holes contribute to the excellent transmission of water vapor, protecting the insulation from unwanted moisture in a perforated film, which has the alternative name "hydrobarrier" or "anti-condensation membrane". The maximum period of trouble-free use of such material reaches 25 years;

fiberglass mesh, closed on both sides with high-density polyethylene, makes up the structure of a reinforced film characterized by high strength.

Source m.7ooo.ru

Such material is most widely used for waterproofing greenhouse roof structures. Reinforced membranes are more securely fixed to the truss system without causing excessive sagging. This contributes to an increase in the efficiency of moisture removal from the internal space of the roof, despite the absence of such quality as vapor permeability in polyethylene films of this subspecies.

Polypropylene membranes

More pronounced strength, complemented by UV resistance, which characterizes the material for the manufacture of such films, allows for a long time to protect the interior of the attic from precipitation. This allows you not to rush with the installation of the top layer of the coating, preparing for the most efficient implementation of the process.

Due to the hygroscopicity of the viscose-cellulose fiber applied on one side of such hydro-barriers, the condensate that accumulates near the surface of the insulation is completely absorbed. Further elimination of moisture occurs under the influence of natural air flows circulating inside the roofing pie.

Source goldkryshi.ru

When installing polypropylene membranes, the viscose-cellulose layer must face the insulation. In addition, to ensure ventilation, it is necessary to maintain a gap between the materials of at least 5 mm.

The unique properties of parchment allow it to be used for insulation against moisture and steam. Liquid bitumen used to impregnate the material prevents wetting. The natural ingredients used in the production of glassine contribute to the absence of the greenhouse effect. The main base component is cellulose.

Many owners involved in the construction of their own houses are attracted by the ecological cleanliness of parchment roof insulation. Also, the advantages of this roll material include ease and accessibility of installation, supported by low cost.

Source tah-heetch.com

In the modern construction market, glassine is represented by three modifications. They differ in the quality of the raw materials used, which affects the final cost of production, and in the abundance of impregnation with bitumen. The most expensive is the "breathing" parchment, represented by the P-350 brands. It is he who is involved in the formation of a ventilated roofing pie.

breathable membranes

They are the most expensive material of all the films under consideration. However, the costs are offset by the quality and durability of the products. In addition, the absence of the need for a counter-lattice is attractive, since the perforated membranes allow fixing directly on the insulation layer.

Source palagkas.gr

The synthetic fibers that make up the basis of the non-woven fabric serve as an excellent protection against wind and moisture. Unlike single-layer membranes, two-layer "breathing" films can be fixed on the insulation on either side.

The division of the considered type of roof waterproofing into three categories is justified by the different level of vapor barrier. Manufacturers provide the following types of breathable membranes:

have the lowest vapor permeability pseudo-diffuse films. Such material requires the arrangement of a ventilation gap between it and the insulation;

characterized by an average level of vapor permeability diffuse membranes;

high vapor permeability is a hallmark super diffuse films.

Pseudo-diffuse films have low vapor permeability Source stroytorgk.ru

Video description

The following video will help you make the best choice of film coating suitable for waterproofing a particular type of roof.

Mounting Features

First of all, it is necessary to observe increased safety measures, since roofing work is carried out at a height. Extreme care is the key to maintaining health.

In general, the process of laying the hydro-barrier of the truss system is not particularly difficult. Even a novice master will cope with such work. The main condition for the successful completion of all manipulations is the presence of a construction stapler and a certain number of metal staples.

Like all construction activities, the installation of a film sheet for roof waterproofing requires preliminary preparation. A good result is guaranteed if the following rules are observed:

minimum distance between adjacent rafters should be 1.2 m;

work is prohibited in wet weather;

required to form gap with a minimum size of 40 mm between the hydrobarrier and the insulation;

the film web is fixed in the direction down up with a slight overlap of about 15 cm;

finally, the laid film should sag slightly to a depth of about 20 cm.

Source lit.sciences-world.com

On the construction market, there are self-adhesive membranes fixed by heating with a burner. All measures for the installation of a profile film web can be divided into several main stages. Each of them requires separate consideration.

Stage 1

The roof surface is free from foreign objects. The rolled web is evenly distributed on the plane, taking into account the overlap. Strips of the required size are measured, after which the film is cut.

Video description

In the video you can see the installation of a waterproofing membrane:

Stage 2

The membrane is fixed with a construction stapler. Thin slats are fixed on top with nails, providing better contact of the roll web with the base.

Film mounting Source thisbuildis.com

Video description

In the video you can see the installation of a waterproofing film:

Stage 3

Since the roof is not a perfectly flat plane, and additional elements are located on it, such as chimneys and ventilation pipes, it is impossible to evenly distribute the entire sheet of the hydro-barrier. Therefore, the film is cut in the required places. To seal the edges, a special paste-like agent is used. The same purpose is served by a special adhesive tape used in the area of the valley and other complex elements of the roof structure.

Video description

The following video shows the installation of Tyvek waterproofing membrane:

Conclusion

Having familiarized yourself with the variety of waterproofing films, having studied their qualitative characteristics, you can make the right choice of material that meets the requirements of a particular structure. A useful recommendation is to ignore cheap products. All costs, of course, are compensated by the long-term trouble-free operation of the roofing system, providing peace and comfort to your home.

A few decades ago, the roof was not supplemented with a waterproofing layer, and it is not at all strange that houses built in the 20th century were so often destroyed. Today, roof waterproofing is one of the most important stages in the structure of premises. The duration of the operation of the roof, and the whole building, directly depends on the correct choice of waterproofing material. The building materials market offers an extensive range of waterproofing for the roof, but the waterproofing membrane for the roof has proven itself better than the rest.

The roofing waterproofing membrane came to us from Western countries, where it was discovered much earlier, and is already successfully used in the construction of new structures. This type of waterproofing material is so advanced that it is able to completely protect the roof from the slightest drops of water. Membrane film is used in all types of premises, including household, industrial and residential.

In fact, membrane films are the same polyethylene options, the difference is that this material for waterproofing consists of many small holes through which steam is removed. The membranes are able to perform the function of not only moisture protection, but also protect the roof from gusts of wind, remove excess moisture from the heat-insulating layer, preventing the insulation from getting wet and rotting. The material can even be used as a temporary roof, the membrane film will protect the room from rain and snow for two months. Among the positive qualities of membranes, one can note their high strength, they are able to withstand 10 kg per 5 cm of film, and stretch well. They do not break during installation, and also have an optimal level of fire resistance, are not susceptible to sunlight.

Types of membrane waterproofing

Waterproofing membranes can be divided into several types:

diffusion;
superdiffusion;
anti-condensate.

Each of the options has its own characteristics and technical characteristics. For example, the diffusion version of the film is characterized by the presence of many holes that do not allow water to pass through from the outside, clearly isolating the room from the liquid, and from the inside, they perfectly pass steam. During installation, the film should be pressed very tightly against the roof, as the pores can become clogged and the steam will not go out well. The diffusion material is environmentally friendly, does not emit toxic substances when heated, and is resistant to the harmful effects of bacteria and fungus. The scope of this type of membranes is very wide, the material is used for waterproofing:

polymer tiles;
slate;
ceramic tiles;
ondulin;
metal tiles.

Diffusion membranes can also be divided into low diffusion membranes - their permeability is less than 300 mg of steam per 1 m2 per day, medium diffusion options carry out from 300 to 1000 mg / m2 per day, and high diffusion material, it has a vapor permeability of more than 1000 mg / m2 / day.

The latter option is also called the superdiffusion membrane. This is a new generation of waterproofing, it is used in areas with a harsh climate and high humidity. Roof waterproofing from this material can last 100 years. The main difference from diffuse membranes is the rate of water and moisture removal. The difference also lies in the manufacturing technique. Superdiffusion materials are made from 4 layers of polypropylene. Such multi-layering gives strength to waterproofing, but at the same time flexibility and stretchability are fully preserved. Unlike most film coatings, superdiffusion options do not require gaps that are left for better ventilation. They can be mounted directly on the insulation, without the use of a wooden lattice.

It is important to note that superdiffusion type cannot be used when covering the roof with a metal seam roof, efroslate, and metal tiles without an acrylic ball. These types of roofing material get very hot in the sun, and when the temperature changes, they form a lot of condensate. To cope with such an amount of moisture, only anti-condensation films are capable of.

The waterproofing of a roof made of metal tiles has its own characteristics, to ensure reliable protection against moisture, anti-condensate membrane films should be used. They do not release excess moisture to the outside, but instead, retain water from the back of the villi. This allows moisture to escape through the air currents of the ventilation gap, the installation of which is mandatory.

It will be interesting to know that, according to laboratory studies, due to moisture retention, condensed heat can increase the insulation of a house by 40% and reduce the cost of heating it.

The anti-condensate film, unlike roofing material and bituminous waterproofing, has a small weight and does not load the rafter system. It is very easy and quick to install and functions well even in full sun.

Trademarks manufacturing membranes

Today, many companies are engaged in the production of materials for roof waterproofing, but, as elsewhere, there are leaders among them that have proven themselves well and there are outsiders, you should not buy goods from which you should not. In the ranking of the best manufacturers of membrane films, the championship belongs to the company Yutafol. The durability of the product has been tested by independent experts, the products have the best performance, are produced in small rolls, and cost $ 1 per linear meter.

In second place is Tyvek, which has been manufacturing roofing building materials for many years. The company's assortment includes "smart" membranes that remove accumulated steam, preventing moisture from seeping under the roof. Membrane-type film can be used for different types of roofing, in addition, there are options that have an anti-reflective coating. They are great for waterproofing residential attics or mansards.

The third place belongs to the company TechnoNIKOL, the products of the campaign are focused not on Europe, as in the previous two cases, but on our climatic zone. The film has a high resistance to tension, is not exposed to ultraviolet radiation and aggressive substances, and is inexpensive from $ 25 per roll.

If you want to provide your home with reliable waterproofing, remember that the choice of membrane film is only half the battle, much more attention should be paid to its installation. If the installation is not done correctly, then even the most expensive waterproofing material will not meet the requirements placed on it.

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

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

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 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

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.

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

How to choose the right membrane

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

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 involve 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. Considering that the savings due to the purchase of budget material in the general mass are 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

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 of the coating used in the arrangement of the roof.

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.

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

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 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.

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

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.

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.

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

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.

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

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

Anti-condensation membrane

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

Also, do not forget about the price. When comparing different types of membranes, it is best to focus on the cost of 1 sq. 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 to fix the membrane with wooden blocks and install the outer 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, compared 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 a 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 commonly used for metal roofs, such as non-acrylic metal roof tiles. 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 - leather. 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.
Double-sided membrane waterproofing 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, the working condition of the roof and the duration of the maintenance-free period largely depend on the competent choice of insulating material and its correct installation.

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