"Izospan V": instructions for use for walls, floors, ceilings. Izospan modification A - an innovative waterproofing material: amenities, benefits, purpose What types of isospan are used inside the house

Almost all heaters that are used in roofing cake today are hygroscopic. They quickly absorb water and immediately cease to perform their functions. And if no insulation for the ubiquitous water vapor is thought out in front of them, then things are bad: the material itself wears out, and the wooden elements of the roof become rotten and become infected with fungus. Therefore, roofers always face a double task: to provide a vapor barrier from the inside of the roofing pie and reliable hydro-wind protection from the outside.

But the wider the range of building materials becomes over time, the more difficult the roofing pies are, and the more individual their protection should be, which will take into account all the features and give the maximum effect. One of these is considered to be Isospan vapor barrier - the company has been operating for almost two decades, holds a leading position in the Russian market and pleases with a good selection of the right products. Let's study the features of such popular films and membranes, the subtleties of their selection and installation.

The domestic brand "Izospan" began to produce its products in the early 2000s. We are talking about the brand of the well-known Russian company Hexa, which now sells its products in all CIS countries. But it is most popular, of course, at home.

Which is not surprising, because the climatic conditions in Russia are such that throughout the year, with the exception of only 3-4 months, the temperature in the house is higher than outside. And this causes such physical processes as the constant movement of air with water molecules upwards.

And the main task of vapor barrier is to prevent the penetration of these molecules into the insulation. After all, if the climate of any region is more or less favorable, then at high outdoor temperatures, this water naturally evaporates from the heater and no one worries about the problems of dampness or fungus. If there is a cold season in the region, then the water remains inside the insulation and quickly destroys it from the inside. But this is already a problem.

That is why the modern choice of films for arranging a roofing pie is huge, and each of them is designed for use in a specific area of ​​construction:

Here is a complete overview of all the roofing films that Izospan produces:

But we note one of the most significant disadvantages of Izospan vapor barrier films: they are not suitable for insulating the roof with inflatable material, as they stretch too much and form pillows. In principle, there are no more negative reviews about Isospan, except for those cases when buyers simply ran into a fake, but more on that later.

Now we propose to carefully consider what roof options this manufacturer offers and for what solutions. Indeed, for each of them, the Isospan vapor barrier has its own technical characteristics and format:

Vapor barrier for insulated roof

We have prepared for you detailed illustrations and master classes of products of this brand. After choosing, the second step is to find out how the Izospan vapor barrier will be attached: instructions for use always come with the products, and each type of film has its own installation features, its own overlap and even its own laying side!

Cheap, but cheerful: universal Izospan V

Izospan B is the most economical material of all offered, it is also universal. He copes well with his main function: they prevent the saturation of the roofing cake with water vapor.

At the same time, Izospan B can be used both for the installation of insulated roofs and for vapor barrier between floors. It is also good in that it prevents the penetration of microparticles of insulation into the room:

For double-sided use: popular Izospan S

The Izospan C vapor barrier has a two-sided structure, where one side is smooth and leans directly against the insulation, and the second is rough and serves as an anti-condensation coating:

In fact, this is the same Izospan B, only more dense and durable.

Special strength: laminated Izospan D

Izospan D is a two-layer vapor barrier material with a laminated polypropylene coating on one side. In fact, this is a membrane with special strength, which is allowed to be used both outside and inside the roof.

Most often, Izospan D is used for waterproofing wet areas, such as a kitchen, sauna, bathroom or home laundry. The installation process of Izospan D looks like this: first you need to arrange a solid boardwalk on the rafters and install the membrane without any sagging (unlike films!), Then fix it firmly. It is necessary to lay such a vapor barrier on top of the insulation, or from the side of the attic, with the smooth side to the roofing.

Reinforced vapor barrier: three-layer Izospan RS and RM

Further, Izospan RS is a three-layer vapor barrier material, which is additionally reinforced with a polypropylene mesh or laminate for extra strength. The rough surface of such a vapor barrier serves as the basis for retaining drops of condensate.

Izospan RM is a reinforced hydro-vapor barrier with a three-layer structure, where polyethylene mesh or laminate is used as reinforcement.

Foil vapor barrier: reflective Izospan FB, FD, FS and FX

The new Izospan line is Izospan FB, FS, FD and FX, four-layer vapor barrier materials with a special effect of reflecting infrared heat radiation. They are great not only for protecting the roof from atmospheric moisture and condensation, but also from overheating of attic spaces in summer. Especially valuable in the arrangement of the attic, because they help to achieve the desired microclimate in them.

There are currently four types of them:

1. The leader in sales for insulated roofs is Isospan FB - foil vapor barrier based on kraft paper, on which metallized lavsan is applied.
2. Vapor barrier FS is made of non-woven polypropylene material and covered with a metallized layer.
3. The FD vapor barrier is a highly durable propylene-based woven fabric.
4. Similar quality FX reflective vapor barrier is made of metallized film and polyethylene foam.

Such a vapor barrier is allowed to be used even at temperatures above 100°C! It not only serves as a reliable vapor barrier, but also reflects heat indoors. At the same time, from the point of view of ecology, all four types are completely safe and have the necessary certificates:

Vapor barrier for non-insulated roof

A roofing cake without insulation also needs a vapor barrier, and the above-described vapor barrier films Izospan D and DM are excellent for this purpose. Such membranes should be fastened with panels across the rafters, and starting from the ridge knot. At the same time, each canvas should cover the second, and all the insulation should eventually form something similar to fish scales:

At this stage, you probably have a question: why in some cases films are needed, while in others the manufacturer recommends membranes? Now we will try to give you the exact answer.

You probably know that all heat-saving materials are divided into types according to the nature of their pores, which are closed and open. The difference is that in closed pores the air does not communicate with atmospheric air, but in open ones it does.

Therefore, if materials with open pores are used as thermal insulation, then it is enough to lay the simplest and most unpretentious vapor barrier (the same film) and to prevent the effects of wind on the other side of the insulation, apply a windproof coating - vapor-permeable membranes. We are talking about special perforated film membranes, which, on the one hand, allow water vapor to pass through, and on the other hand, retain water.

And even if you use a rather weak vapor barrier on open-pore insulation, but on the other side of the insulation there is a vapor-permeable membrane, then such a design can also be considered competent and reliable. It is only important, guided by modern SNIPs, to organize natural ventilation with the help of holes in the ridge.

But, if the construction of the roof of your house is quite complicated, then instead of Isospan D or DM, use the novelty of the market - Isospan AQ proff. This is a new vapor-permeable three-layer membrane, which is considered professional. It is laid on the insulation from the side of the street, as a hydro-wind protection that allows steam to pass through.

Vapor barrier for attic floor

Here are the main types of vapor barrier films that are used to insulate the ceiling:

These are membranes such as Isospan A, A AS and AM. They are not only waterproof, but also do not let steam through.

Lay Izospan B in the attic floor with the rough side down, between the finishing materials of the floor and the draft ceiling, or with the rough side up along the floor beams above the insulation. At the same time, be sure to leave a ventilation gap of 3-5 cm and glue the places where the vapor barrier adjoins other surfaces with special adhesive tape:

In a standard attic construction, you can also safely use such a vapor barrier from the same manufacturer as Izospan FD, FS or FX (we considered them above). These are also insulating materials, but they combine the functions of vapor barrier and reflection of heat flow. It is necessary to lay such materials between the ceiling finish and its rough design, overlapping from 15 to 20 cm, or back to back, if we are talking about Isospan FX.

The main thing is to put them on the right side: the reflective surface - inside the heated room. And overlap such canvases with the help of metallized tape Izospan SL. At the same time, it is necessary to leave a gap of 4-5 cm between the interior decoration material and the reflective surface of the material. And where Izospan adjoins a concrete or wooden surface, glue with Izospan ML proff tape.

Flat roof vapor barrier

In a traditional flat roof, the vapor barrier is placed on the base under the insulation, and its main task is to prevent either moist air or condensate from rising above:

Both Izospan D and Izospan RM are suitable for arranging a flat roof. The only difference is that Izospan D is a two-layer material, and Izospan RM is a three-layer and more durable, dense material. This is indispensable if mistakes were made in the construction of a flat roof and its base is not airtight.

The choice of isospan tapes for different tasks

To properly install the Izospan vapor barrier of this brand, you will need one of the special accessories from the same manufacturer. Most of these adhesive tapes are double-sided tape, which is quite simple to work with:

• Izospan SL is a vapor-waterproof adhesive sealant with a double-sided adhesive layer, which must be fixed with a metal bar.
• Izospan KL is an adhesive tape that has one side, with a metallized coating.
• Izospan ML proff is a one-sided super-adhesive tape, which is reinforced with fiber. It differs from others by especially high adhesion and is used for sealing vapor barrier on absolutely any surfaces: brick, concrete, metal, foam and plaster.

By the way, just at this stage of work, many are tempted to purchase the most ordinary adhesive tapes instead of branded ones. Why not, you ask? But in fact, such tapes can withstand no more than three days of frost or heat. Here is a good overview of professional vapor barrier tapes, among which Isospan ones take pride of place:

And now let's describe the whole process of installing a vapor barrier using such tapes in steps:

• Step 1. First you need to assemble a frame for insulation - from timber, boards, slats and plywood.
• Step 2. Next, we sheathe the frame with wind protection, especially paying attention to the knots around the pipes (if any).
• Step 3. We insert cotton wool (mineral or stone) between the rafters, which will be held in this position due to elasticity. At the same time, the height of the wool should be less than the height of the rafters by 4-5 cm.
• Step 4. After you insert all the insulation, fill up all the cracks, dents and gaps. It is very important! Make sure that there is no possibility of thermal bridges anywhere, and only then proceed to the vapor barrier.
• Step 5. Now we spread Izospan vapor barrier sheets on the insulation. The vapor barrier film itself must be fastened to the rafters without much stress, even with a sag of up to 2 cm, so that it does not tear further from temperature changes.
• Step 6. Stick a strip of cloth and tear off the protective layer. If you pass through a place where the integrity of the roof is broken, for example, a window or an antenna, then you need to cut a hole and attach the vapor barrier using Isospan double-sided tape.
• Step 7. Press the second sheet of vapor barrier on top, press down and iron. If you will meet two strips of vapor barrier, then it is better to glue two tapes on them - for reliability. But with Izospan FL metallized tape, you need to glue the joints of two layers of vapor barrier, right on top.
• Step 8. On the other side of the insulation, on top of the roofing pie, we stretch the hydro-wind protection right along the rafters, and press it with the bars of the counter-lattice.
• Step 9. We mount the roofing, observing the air gap between the top film and the roofing. These ventilation ducts must be open at the window and ridge assembly so that air can move freely there.
• Step 10. Inside, we close the vapor barrier with a finish. Also, if you are making an inner lining with a horizontal clapboard, then the vapor barrier can be mounted vertically, and the vertical canvases can be sealed with butyl rubber tapes. And do not spare the adhesive tape on particularly difficult areas!

During work, make sure that dust does not settle on the vapor barrier, it is better to carry out preliminary cleaning for this purpose, otherwise the isospan tape will not adhere well. And if you have worked with insulation before, you will notice that a lot of small particles and fibers always remain from it.

And the last step is to make a close inspection so that the tape fits snugly against the vapor barrier everywhere, there is uniform tension everywhere, and in general the work done should look neat.

We also present to your attention an unusual master class for installing Izospan vapor barrier, where two types of adhesive tape are used at once - Izospan KL and Izospan FL (just remember that you can work with such tapes only at a temperature of + 5 ° C):

And, finally, our last advice when working with Izospan products: if we are talking about the insulation of the attic, which is made on a wooden frame, vapor barrier must be arranged along the entire contour of the room: both along the roof and along the walls.

This is especially important if she has an open staircase, because then warm air from all over the house will accumulate in the attic, and it will become the warmest in the whole house. But in this case, the water vapor will just be drawn into the cooler lower floor (the air is always warmer in the attic), which is also not very good, although it is easier for the vapor barrier of the under-roof space. In this case, carefully consider the ventilation of the house, and in extreme cases, organize a separate staircase with doors for the stairs.

How not to run into a fake, or where do such different reviews come from?

You will be surprised how among the majority of positive reviews about Izospan there are single sharply opposite ones. Indeed, how can the same product perform wonderfully in the construction of one house, and completely disappoint in other hands?

In fact, the problem is not only whether the vapor barrier was laid on the right side and how tightly the joints were glued. Unfortunately, it happens that a person simply ran into a fake, and one such underground workshop was once discovered even in Moscow. Therefore, when buying, pay special attention to such markers:

A really high-quality product does not cost much more than conventional films, but it completely takes care of all the problems associated with vapor barrier!

Every person sooner or later you have to make repairs, and sometimes build a house. It is not worth spreading about the number of problems and questions that arise even during the first of the processes, since there are a huge number of them.

Now the conversation will go about one of the stages of building a house that you can’t miss in any way, and you might not even have heard about it until today. The topic of today's guide is isospan.

What it is, how to use it, what types of isospan are, etc. Below you will find answers to all the questions asked, as well as some useful tips that will be useful to you during your work.

Purpose and characteristics of vapor barrier isospan

Izospan- this is a vapor barrier material that is produced in rolls and is used to isolate the walls and roofs of buildings, floors and ceilings, from the ingress of steam and moisture from the inside. In addition, this film limits the occurrence of condensation on the surfaces of walls and roofs, which can significantly increase the life of the materials used.

If you do not use such material, then the insulation, which is usually placed in the layer between the roof, walls and the interior, will quickly lose all its heat-saving properties, and may even collapse.

However, call isospan a film- this is not entirely correct, because, despite the fact that the polymer film is the basis for its manufacture, after adding various minerals and substances, the polymer acquires much more useful properties.

Isospan today many different companies produce, and therefore it should not be difficult for you to find and purchase it.

Installation of material Izospan A

This material is mounted mainly for the vapor barrier of roofs and attics, as it is insensitive to ultraviolet radiation.

Required Tools

• metal profile and wooden slats;
• self-tapping screws;
• construction stapler and adhesive tape;
• scissors for cutting the coating;
• vapor barrier (calculate as follows: the sum of the surface area to be covered and overlaps of 15 cm on each side).

Step-by-step instructions for installing Izospan A material

1. When installing the Isospan A vapor barrier on an insulated roof, the material is cut into wide strips and overlapped. The smooth side of the vapor barrier must remain outside.
2. Installation of Izospan A should begin from the bottom of the roof. Izospan must not be allowed to come into contact with the insulation, as this can significantly reduce the waterproofing properties of the material.
3. It needs to be mounted directly on the rafters of the roof slope, you can strengthen the structure with guide rails or self-tapping screws. But this only applies if if you mount this film as the last layer of vapor barrier. In other cases, it will be attached directly to the roof from the inside.

• Between the film and the roof itself it is necessary to leave a ventilation gap, its thickness should not exceed five centimeters. About four would be perfect.
• Roll material, which means that joints will form. In such places, it is necessary to deploy isospan overlap.
• All joints– at the walls, in the corners, between the layers of the film, you need to glue it with adhesive tape. This will keep the tightness.

Vapor barriers for roofs and walls, its types

Vapor barrier required in every building, since it is one of the elements of moisture insulation, and none of the materials used today can boast of completely ignoring the moisture that has fallen on it. So it is strongly not recommended to ignore this stage.

Use vapor barrier, as it was already written earlier, to protect building structures from the ingress of steam and moisture from inside the premises. Thus, condensate does not accumulate, which means that damage cannot reach an alarming size.

In addition, on the walls and in the roof that are protected in this way, fungus will not appear, as well as various types of mold - this will also affect the life of the whole house. So these are not the distinctive characteristics of isospan, but just general functions that any vapor barrier will perform.

In order not to list the various materials that are used in production, it is better to divide the vapor barrier into several types, depending on its properties:

1. Standard vapor barrier film- it is used longer than all the others, and perform only one function, keeping steam and moisture out of the insulation and other internal layers, up to the wall or roof itself. It is the easiest to use - it is easier to find such materials, and they are much cheaper than their more modern counterparts.
2. The vapor barrier can be equipped with a reflective layer- it will not only protect the inner layers from moisture, but also reflect infrared radiation back into the room. In this way, heat is retained in the house, which greatly increases the value of such a film. You will pay more for the reflex layer than if it were not there - but you are unlikely to regret such a waste of money, since the efficiency of this method of preserving heat is more than just high.
3. Vapor-permeable films- it may seem nonsense to use a vapor-permeable material for vapor barrier, but everything is a little more complicated here. The condensate will still not settle on the insulation or anywhere else - the technology is such that excess moisture is simply removed outside the house. Naturally, the cost of such films is several times higher than conventional ones, but it's worth it. Although, if you do not plan to arrange a bath indoors, this may be an extra precaution.

So, as you can see for yourself, you have a fairly wide choice and there is really something to think about.

Isospan varieties

Izospan, as already mentioned, is a membrane film that provides the inner layers of the roofing and wall "pie" with protection from steam and moisture, which, condensing, can damage them.

Given the number of types of vapor barrier films, we can assume that isospan also gives its users some choice - and you will not be mistaken with the conclusions.

Izospan can be of several types, one might say, special modifications of the same film:

The first four types are designated by the manufacturer as wind and moisture protective films, the second four are designed for hydro and vapor barrier, but the latter are distinguished by a metallized structure - and it is they who have the necessary qualities to reflect infrared radiation back into the room.

Technical characteristics of isospan

It is rather difficult to answer this question unambiguously, since each of the species (and, as you can see, there are quite a lot of them), has its own characteristics that distinguish them from the rest.

It would be best to again divide all the views into groups, which will save you time:

1. Group A films, including all subspecies, they are distinguished by increased protection from the outside of the building, that is, they can be used not only as a vapor barrier, but also as a wind and waterproofing material.
   If the package says BUT, then this is a regular film without any additives. AM and AS, these are already films with increased protection - they are made up of three layers of material, the first being somewhat thinner than the second. Also in this group there is a fire-resistant film and professional, designed to work in all weather conditions.
2. The second type is intended mainly for interior wall and roof cladding. That is, this is exactly the vapor barrier in question. The first type is here AT- it is made up of two layers and has good properties for retaining moisture and evaporation.
   FROM intended mainly for concrete, cement and even earthen surfaces. Film option D has increased stability, since its basis is a woven polypropylene fabric. It is best used in rooms with high humidity.
3. The third group is the most special. For example, FD made with a duplicated metallized film, it can be used in roofs and walls, even if not insulated beforehand, which greatly increases its value. FS differs from the previous subspecies only in price - it is cheaper, because it is less durable.
   Facebook films are made from kraft paper, it is pre-coated with a special layer of lavsan, which will reflect heat. It is this material that should be used in baths and steam rooms. FX in turn, it can play the role of additional thermal insulation due to its large thickness (2 - 5 mm).

Installation instructions for other types of Izospan

Izospan V

Since the scope of this type of isospan is mainly indoors, you need to remember about the "pie" technology, that is, about the order, in which layers of material are to be laid:

1. Roof;
2. Izospan group A or its subspecies;
3. Reinforcing crate and ventilation gap;
4. Isospan itself;
5. Rafter;
6. Interior decoration and decor;

Thus, a multilayer structure is created, protected from harmful moisture vapors. Here you also need to remember about the tightness and overlapping of the film in difficult places.

Izospan C

Unlike other types, FROM it is used even in cases where the slope of the roof is quite small - up to 35 degrees. So, most attics are provided with protection from moisture with its help. In addition, this film is also used in basements to avoid condensation.

Mounting order:

1. A vapor barrier is stretched onto the roof from below. It must be remembered that strong tension is not needed - the isospan membrane needs free space.
2. The edges are fastened with a construction stapler, and for the sake of tightness, everything is also sealed with adhesive tape.
3. overlap in 15 - 20 centimeters is required.
4. Whole structure after tension, they strengthen it with a crate or simply with slats, all work is done with self-tapping screws or with a hammer and a handful of nails.

Izospan DM

Isospan installation of this type is also produced mainly on sloped roofs that have not been previously insulated. This is due to the multi-layer nature of the film itself and the presence of a powerful anti-condensate layer. All this protects the interior, as well as the roof itself from moisture.

Installation is carried out in the same order as described in the previous paragraph of the plan. Unless, in order to avoid sagging of the material, you can use a boardwalk or crate inside the roof - it is installed on the rafters.

Izospan AM

To properly install this film, you do not need to have professional skills, because the whole point here is to simply observe specific course of action:

1. Roll out the material over the insulation and cut it.
2. Lay the film overlap;
3. Strengthen the edges with a construction stapler;
4. Seal the joints with construction tape;
5. Nail the structure with rails;
6. From above, mount the crate or flooring;

Important! If the flooring is mounted, then a sufficient gap must be left between it and the isospan film. For this purpose, use the counter rails on which the flooring is attached, with a thickness of four to five centimeters.

Advantages and disadvantages of isospan vapor barrier

Preimu
Isospan's benefits are that:

• It is strong enough for its function;
• Has high ability to waterproofing;
• Resistant to various types of corrosion - including fungi and molds;
• The temperature regime of operation is extremely wide - from sixty to eighty degrees;
• Mounted extremely easily;
• Eco-friendly in production;
• Has a high warranty period;
• The price of isospan is about a third less than that of other vapor barrier materials;
• Easy enough to install following the instructions.

There are only a few shortcomings:

• Films are very unstable in case of fires(at least most species), and therefore you cannot work with open fire;
• The most inexpensive of films require careful handling, otherwise, you can be left with a “broken trough”, that is, with a torn film.

Izospan is a film coating used for insulation purposes. It is necessary so that the thermal insulation retains all its key parameters throughout its service life. Insulation materials actually provide protection for the home, keeping you warm in inclement weather and providing comfort in the heat of summer. It is 100% polypropylene.

Even at the construction stages, you can form a barrier, designed to ensure the preservation of heat, using Izospan in the arrangement of vapor barrier. There are several types of this material. The film is presented in a large assortment and differs in its purpose. Vapor barrier films and membranes are able to completely or partially pass moisture and air from one side. Some modifications are used to enhance the characteristics of the base materials.

What are the characteristics of Izospan:

For Izospan, a different scope is envisaged. The main area is still the construction area. The material has:

• unique structure;
• own marking;
• individual specifications.

Manufacturers use the letter designations of various modifications of Izospan. Sometimes these indices are combined in a number of models, due to which diversity is formed in terms of installation and scope of Izospan.

Model A

Izospan, And the technical characteristics are as follows.

First, by analogy with a check valve, the membrane easily passes water vapor that comes from thermal insulation. Thus, natural ventilation is provided. On the other hand, Izospan of this type is able to block the penetration of moisture from the outside and does not allow condensation to form. The structure of the insulation remains unchanged, even if there is a strong wind outside.

From the outside, Izospan is equipped with a layer of waterproof material. For this reason, it is often used in the arrangement of roof structures. It also finds application as protection for walls and ventilated facades. Due to the property of waterproofing, which is characterized by Isospan, its membranes increase the service life of thermal insulation. Even the best insulation is destroyed sooner or later due to the effects of wind. Izospan, A is ideal for outdoor protection of the home.

The membrane must be laid on the outside, on top of the insulation. That is, its smooth side should look out into the street, which can be quite easily determined by touch. The roll is divided into wide strips of suitable size. Following these, it is carefully spread with an overlap with the next layer over the entire area.

Roof vapor barrier

Arrangement of hydro and vapor barrier of the roof begins from the bottom. When laying out the membrane material, contact with thermal insulation should not be allowed. This will reduce the ability to resist moisture. To understand what is at stake, it is enough to imagine the following situation. Let's say a person goes on a hike. He took with him a canvas tent, which was used in Soviet times. If during the rain you run your finger along the roof while inside, then after a few minutes it will start to drip from this area. Izospan works in a similar way. It is always equipped with a double crate.

Izospan is equipped outside, laying on a crate of slats. The membrane structure increases the degree of insulation. At the same time, it contributes to the increased life of the structure as a whole. It is very important to prevent all kinds of swelling and sagging during the operation of the roof. Otherwise, you will have to listen to the sounds of the wind with characteristic sounds when the membrane knocks on the roof. The use of thin rails is enough to fix Isospan, leaving 3 cm to the insulation.

Thus, the previous view of Isospan is able to protect from the wind. In addition, it acts as a reliable hydro-barrier for the insulating material. But it does not solve the problem in the form of condensate. It must be prevented from entering through the membrane in the form of vapor. If the thermal insulation is saturated with at least 5% moisture, the thermal insulation performance of such a roof will drop by 2 times. In the future, the condensate will fall on the metal tile. The roof will turn into a kind of colander.

Specifications Izospan B has the following:

• ability to resist condensate;
• excellent waterproof properties;
• vapor barrier effect.

Carrying out the installation of various materials during the arrangement of the roof, it must be understood that even the highest quality roof insulation is saturated with water vapor at some point.

Izospan B forms a barrier to internal steam. Its structure consists of two layers:

• the first has a smooth surface and is adjacent to the insulation during installation;
• the second, fleecy to the touch, absorbs condensate.

The installation of the coating is carried out in all cases with the fleecy side down. There must be a gap between Izospan and finishing materials so that air circulates freely in space. It also prevents the accumulation of moisture. Izospan B is overlapped. At the same time, a capture of 10 cm from the side of the insulation is observed, at least. Secure it with a construction stapler.

Izospan C

In its structure there are two layers: smooth and fleecy. The latter is responsible for the retention of condensate. Later on, it fades away. Modification A forms a vapor barrier for the insulation, preventing the evaporation of water particles formed in the room from being absorbed. The material is used for:

• building walls;
• installation of sloping and insulated roofs;
• arrangement of interfloor ceilings.

Vapor and waterproofing is installed in various cement screeds, and Izospan C is also used for laying flat roofs. Thus, in terms of characteristics and structure, this material is in many ways similar to Izospan D. At the same time, it has an increased margin of safety. Accordingly, it is possible to obtain, thanks to it, a very dense panel with increased reliability indicators. . At the same time, Izospan C is about 60% more expensive in price..

Specifications:

• maintains temperature range from - 60 to + 80 degrees Celsius;
• impervious to steam;
• has the ability to resist water. This figure is 1 thousand mm of water column.

Izospan C is sometimes used for arranging concrete floors. It is placed smooth side down. It finds application for laying horizontal type wooden floors and similar structures in the attic. In the latter case, the vapor barrier is spread over the insulation.

On sloping roofs, the canvas is laid in the direction from the bottom up. The material is overlapped by 15 cm. To avoid depressurization, the joints are glued with adhesive tape on 2 sides, by analogy with double-sided tape. To fix the structures, slats with a diameter of 5 cm are used. Between the vapor barrier and the tiled roof, the gap should be at least 5 cm.

Izospan is spread over the insulation. It is necessary to provide a special gap of 50 mm in diameter to ensure ventilation. It is about the distance between the thermal insulation and the cloth. When arranging a concrete floor, Izospan C is overlapped. After that, a cement screed is applied to the canvas. Only after this is the flooring installed..

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Izospan D

Suitable for the construction of various types of structures. Able to withstand moderate mechanical stress. At the same time, it demonstrates good resistance to tearing and withstands the effects of wind. In winter, it can cope with loads in the form of snow accumulated on the roof. It is considered one of the most reliable and durable options.

Its characteristics:

• completely impervious to water;
• has high strength;
• It has a laminated one-sided coating based on polypropylene.

Can be used on all types of roofs as it forms a barrier to condensation. It is used for various buildings and structures in order to form hydro- and vapor barriers. Able to largely withstand adverse weather events. It is often used on construction sites for temporary roofing. It can play the role of a protective wall in facilities under construction. Such a roof can last up to 4 months. Izospan D is popular for arranging concrete floors that require a waterproofing layer, protecting against moisture from the ground.

Thus it is used:

• to protect wooden structures if an uninsulated roof was used;
• as protection against condensate forming under the roof;
• when arranging the basement;
• during the installation of concrete floors;
• for protection from adverse weather conditions.

If it is necessary to protect the internal parts of the house from exposure to vapors that are the result of vital activity, and to extend the life of the insulation, then it is better to use Izospan D. It can be spread immediately on the rafters, having previously insulated the surface of the pitched roof. The layers of material in this case are the same, and therefore you can not figure out which side to lay Izospan to the insulation.

Mounting is done in a horizontal orientation, overlap. The material is cut into sheets of the required size. Start work from below. In the process of laying, bayonets are glued with tape. Surfaces that are adhesive on both sides connect two sheets of hydro- and vapor barrier between themselves. Izospan is fixed on the rafters with staples of a construction stapler or wooden slats.

Izospan is a non-woven building material that is used for insulation of residential and non-residential premises. In addition, it is necessary to protect against moisture and water. This is especially important when creating a house plan with an attic and a garage, which must be insulated with high quality water and heat.

The reader will learn in this article what types of isospan exist, what advantages this material has.

Isospan film is now very common in the construction market. It is used as the first barrier layer during the installation of insulation: it prevents moisture from entering the main heat-insulating layer of expanded polystyrene or other insulation. The material consists of pure polypropylene, fully synthetic, therefore it does not completely absorb water. When creating an insulation plan, isospan should be taken into account in the work.

Attention! Izospan is recognized as a very effective material for insulating attics, garages, one-story buildings.

An attic is an attic space that can be used for storage or as living space. The roof itself becomes the walls of this room, which should be well insulated. Izospan insulates and protects against moisture and wind, maintaining a comfortable temperature inside the attic and the whole house.

Similarly, isospan coating is used to insulate garages and other one-story non-residential premises:

• protects metal from corrosion, wood from decay;
• prevents the occurrence of condensate and moistening of the insulation, which reduces the thermal insulation properties;
• reflects air currents, protecting the room from cooling and drafts;
• maintains a stable temperature inside the room, does not release heat.

The following advantages of isospan can be distinguished:

• waterproof;
• durable and environmentally friendly (does not emit harmful impurities);
• has high elasticity;
• protects from ultraviolet radiation;
• protects from the wind;
• does not release, reflects heat;
• withstands high pressure;
• durable (serves about 50 years);
• retains its properties in the range from minus 60 to plus 80 degrees Celsius.

In terms of creating comfortable conditions inside residential premises, isospan plays an important role, especially when equipping a house with an attic, a garage and other one-story outbuildings in the Russian climate.

Varieties of material, their technical features

Now high-quality manufacturers create pure polypropylene and a film from it using high-tech equipment, controlling the quality of production. In Russia, domestic companies are opening that offer building materials similar to foreign companies in quality and more favorable in price.

When choosing products, you need to focus on the presence of isospan quality and safety certificates. Well-known manufacturers coordinate their production plans with legal requirements.

Now, when decorating houses and non-residential premises, 4 main modifications of isospan are used, which have their own characteristics.

Isospan A

This is a film (membrane), which perfectly waterproofs and helps to eliminate moisture, its vapors, from the insulation. This modification is used to protect against wind and water, increases the life of the insulation. It is applied to isolation of private houses, penthouses, garages and any other rooms.

This isospan is resistant to mechanical stress and pressure, completely neutral to bio-impact (mold, bacteria, etc.). Can stretch:

• longitudinally by 190 mm;
• transversely by 140 mm.

The material is fixed from the outside of the insulation as an additional barrier. For example, when insulating an attic, it is mounted on the roof with an overlap in wide strips.

Important! The smooth surface should remain outside, the film itself should not come into contact with the insulation material. Otherwise, isospan will not be able to qualitatively waterproof the room and the insulation.

It is necessary that the membrane lies flat, does not protrude, swell or sag. Izospan A is fixed with wooden slats and nails.

Izospan A can be seen in the photo:

Izospan V

This modification perfectly blocks the way for water vapor, which eliminates the impregnation of the insulation with steam.

Important! When creating a garage plan, this can be very important to keep the room where the car is stored from getting damp.

Izospan B is two-layer, used:

1. On pitched roofs.
2. On the walls: external and internal.
3. To save floors in the basement, attic (attic).
4. In garages and other non-residential premises.

The vapor permeability index is 7, the material can also be stretched: in the longitudinal direction by 130 mm, in the transverse direction - at least 107 mm.

Each layer of this material has its own functions:

• fleecy layer retains moisture and condensate;
• the smooth part allows you to firmly fix the film with insulation.

Unlike the previous modification, isospan B is attached to the inside of the insulation. Fastened from the bottom up and overlapped. In order for the film to capture vapors, condensate, there must be a free space of at least 5 cm above the fleecy layer.

The appearance of the packaging of isospan B can be seen in the photo:

Izospan C

It also consists of two layers, but is used to protect an uninsulated roof, floors between floors, floor insulation. Has high strength.

The film is used for steam and water insulation:

• uninsulated pitched or flat roof;
• frame, load-bearing walls;
• wooden floors parallel to the floor;
• concrete floor.

1. Installation of non-insulated roofs (slopes) is carried out with an overlap (with a depth of about 15 cm), also fastened with wooden slats. When arranging the attic at home, this material perfectly isolates the room from moisture from the environment.
2. If we talk about wooden floors, then here the film is attached directly to the insulation with a small free space from the floor (4-5 cm).
3. When insulating a concrete floor, isospan C is placed directly on the floor and pulled together on it.

Izospan C can be seen in the photo:

Izospan D

This modification is very durable, able to withstand great pressure and loads. It is used in roofing. In terms of waterproofing and protection against condensation, it perfectly withstands even a large crust of snow on itself.

Great for arranging the attic of a house or garage in regions with heavy snowfall. The material protects wooden structures and non-insulated roofs. Isospan D is insulated:

• flat and pitched roofs;
• concrete floors and ceilings at the basement level of the house.

The high strength of the film allows you to protect the living area from wind and moisture, even in cases where the roof passes moisture.

It is also mounted with an overlap horizontally in strips, fixed on the rafters of the roof of the house with the help of rails. Installation on a concrete floor is similar to the previous modification of isospan, because in many respects isospan C and D are similar in their characteristics.

Izospan D can be seen in the photo:

The main modifications of the building material are described above, there are also varieties of these modifications that have different densities or additional qualities, for example, fire retardant additives, which provide greater fire safety and protect against fire.

Also, manufacturers took care of the creation of additional consumables in time, which allow isolating seams and minor damage. We are talking about isospan adhesive tapes - these adhesive tapes allow you to isolate seam lines, uneven surfaces. It is enough that the work surface is dry and clean - isospan FL, SL adhesive tape will provide good impermeability of such places. There is even a metallized tape that has a high resistance index.

Important points for installing isospan

In the instructions for the use of isospan, the following points can be distinguished:

1. Laying this insulating material does not require any special knowledge, it can be done by hand, taking into account the individual characteristics of the membrane.
2. The sales kit is always accompanied by instructions, which must be read carefully and acted according to the instructions. For example, if you fix isospan with the reverse side, then all the work will be meaningless - no isolation will occur.
3. Fastening to the tree occurs with the help of a stapler, one should not forget about sealing the seams, possible cracks with the help of isospan adhesive tape.
4. When a heat-insulating film is mounted, the metallized part should look inside the room, and the laying work itself is carried out butt-to-butt, without overlap. The seams are also sealed.

Izospan allows you to make life in your home comfortable and warm. The use of this film in the basement or in the attic prolongs the service life of the truss system, wooden floors, creates a stable microclimate in residential premises. Isolation of the garage from moisture and condensate, allows you to make the room dry and safe for the metal coating of the car and other equipment.

Modern technologies greatly simplify the arrangement of your home. Approaching the issue responsibly, each person will be able to not know the problems in his home for a long time!

Izospan is an insulating film coating. The main purpose of the film is to ensure the preservation of the original characteristics of thermal insulation throughout the entire service life. It is difficult to imagine a modern construction site without the use of various types of thermal insulation. Mineral wool, Penoplex, Isolon, Izover, various polystyrene foams and just polystyrene - all these materials require their own protection.

Thermal insulation materials practically envelop our house, retain heat on frosty and rainy days, create comfort in the hot summer season, preventing the penetration of heat flows. But how to protect the thermal insulation belt from negative atmospheric phenomena? Reliable protection against moisture, rain, destructive wind, is designed to provide 100% polypropylene, with a proud name - Izospan.

To create a barrier even at the stages of the construction process, to perform the function of protective insulation for thermal insulation, this is the true purpose that isospan vapor barrier successfully performs. Despite the apparent simplicity, the material varies by type.

We bring to your attention - Izospan instructions for use. Understand: isospan which side to lay. Consider isospan technical characteristics, and isospan laying method.

Worthy competitors isospan:

• Vapor barrier Tyvek;
• Vapor barrier TechnoNIKOL;
• Vapor barrier Nanoizol;
• Vapor barrier Ondutis;
• Vapor barrier Yutafol.

Before proceeding to a detailed review, it should be clarified that the films are presented by the manufacturer in a wide variety and have different purposes. Vapor barrier films and membranes are divided into absolutely vapor and hydro-impermeable and partially moisture-permeable only in one direction. Some of the materials successfully complement the thermal insulation, enhancing its characteristics.

Izospan vapor barrier technical specifications

• The material is waterproof;
• Elasticity is beyond praise, the most difficult sections and bends are easy to bypass;

• Resistance to influence of ultra-violet radiation;
• Resistance to negative atmospheric phenomena;
• Does not emit harmful substances. Safe for human health. Does not harm the environment.

• Withstand temperature differences in the range from – 60 °C to + 80 °C
• The refractory elements added in production determine the G4 combustibility group, according to fire hazard, which is confirmed by the relevant certificates.

Izospan has various applications, given the area of ​​\u200b\u200bbuilding use. Izospan insulation, unique in its structure, has individual technical characteristics and its own marking.

Manufacturers classify their products with letter indices A, B, C, D, F, R. The combination of letter indices adds numerous variety, applications and installation of isospan. Each new designation implies its own isospan application. This fact must be taken into account in the construction of your home.

roof vapor barrier isospan

Isospan A

The membrane, like a non-return valve, freely passes water vapor from the thermal insulation side. Does not interfere with natural ventilation of the insulation. On the other hand, it reliably blocks the penetration of moisture from the external atmosphere, prevents the formation of condensate, and prevents the wind from destroying the structure of the insulation.

Due to the water resistance of the material on the outside, the membranes are widely used in the installation of roof structures, they are widely used as protection for walls and ventilated facades of buildings and structures. any destination. The waterproofing property that the isospan membrane has for a long time extends the life of the thermal insulation. Even the best insulation breaks down over time under the influence of wind, application Isospan A will be the ideal solution to protect the house from the outside.

In a nutshell, we’ll clarify which side to lay on the insulation Isospan A. The question of which side of isospan A should be laid is far from idle. As we noted, its work is carried out on the principle of a check valve. Or, if you want: - let everyone out, don't let anyone through. It is necessary to lay the membrane from the outside, on top of the insulation.

The smooth side, which is easily determined by touch, should “look” at the street. The roll is cut into wide strips of suitable size, after which it is carefully spread over the area with an overlap with the next layer.

Roof vapor barrier

Roof waterproofing starts from the bottom. When laying Izospan A membranes, contact with the thermal insulation material should be avoided. Touching the membrane significantly reduces its waterproofing properties. Probably those who went camping with their grandfather’s canvas tent noticed that if you run your finger along the “roof” from the inside during the rain, then literally in 10 minutes it will drip in this place. It is for this reason that the laying of Isospan A is allowed only with a double crate.

Isospan flooring is carried out outside the thermal insulation on a crate of laths. The use of a membrane increases the degree of insulation and extends the life of the entire structure. It is extremely important to control the absence of possible swelling or sagging during work. Otherwise, you will become a constant listener to gusts of wind with the characteristic sounds of the beating of the membrane on the roof. Thin rails are enough to fix isospan A, leaving 2-3 centimeters of free space to the insulation.

Izospan V

As we found out, isospan A, firstly, protects against wind, and secondly, it will create a powerful hydro-barrier for insulation. The danger remains in the form of condensate, wetting of the insulation - condensate, which, before passing through the membrane in the form of steam, will saturate the thermal insulation with moisture. Humidification by only 5% will lead to a decrease in thermal insulation performance by half. A further perspective is the penetration of condensate onto the metal tile, with the subsequent transformation of the roof into a colander.

The anti-condensation surface in combination with the vapor and hydroprotective effect will save you from such troubles. When carrying out installation work on the arrangement of the roof, one must clearly understand that even the best roof insulation is gradually saturated with water vapor.

Creating a barrier to internal couples - Izospan V will serve as a kind of vapor barrier. The material consists of two layers, a layer with a smooth structure adjoins the insulation during installation, the second fleecy side is designed to absorb condensate.

That is why, the installation of the coating is always carried out with the fleecy side down with a gap to the finishing materials, for ventilation and drying. Type B is overlapped with a grip of at least 10 centimeters from the side of the insulation and fastened with a construction stapler or otherwise.

Izospan C

The structure of the material combines two layers: on the one hand, a smooth surface, on the other, a fleecy one. The fleecy layer retains condensate with subsequent weathering. Izospan C creates a vapor barrier for insulation, preventing the absorption of vapors of water particles formed inside the room. The material is widely used in the construction of walls, the installation of insulated, sloping roofs and interfloor ceilings. Vapor waterproofing using type C, is installed in various cement screeds, and in flat roof structures.

In a word, in terms of structure and characteristics, the material is very similar to type B. At the same time, it has an increased margin of safety and, therefore, the reliability of an ultra-dense panel is higher. Izospan C to buy will cost the consumer more than type B by about 50-60%.

Characteristics of isospan Type C:

• 100% polypropylene;
• Applicable temperature range -60 – +80 °C;
• Breaking load: longitudinal // transverse. H//5cm not less than 197/119
• Vapor proof
• water resistance not less than: 1000 mm w.c.

The use of isospan C:

1. Sloped roof with an "overlap" of at least 15 cm
2. Floor protection in the attic. A layer of vapor barrier, spread on top of the insulation, smooth side down;
3. Concrete floor. spread on a concrete surface, smooth side down;
4. Wooden floors of horizontal execution.

The flooring of the canvas on sloping roofs should be done from the bottom up. The material overlaps about 15 centimeters. Overlapped joints, in order to avoid depressurization, are glued with a special adhesive tape from the sides, similar to double-sided tape. The structure is fastened with slats of 5 cm thickness. A gap of at least 5 centimeters is left between the roof tiles and the vapor barrier layer.

Izospan C is spread on top of the insulation, it is necessary to leave a gap of about 50 millimeters from the panel to the heat-insulating material for ventilation. In the device of a concrete floor, type C is overlapped on a concrete surface, then a cement screed is laid on the canvas, and only after that the floor covering is mounted.

Izospan D

High strength, fully waterproof waterproofing material. Polypropylene cloth with a one-sided laminated polypropylene coating. The versatility of the moisture-vapor-proof material means that it is widely used in construction technologies in the construction of any type of structure.

Izospan D successfully resists moderately strong mechanical loads, is resistant to tearing, withstands strong gusts of wind, and in winter copes with a large snow load. In comparison with other similar films, Izospan D has gained fame as the most durable and reliable option.

Izospan D Scope

In any type of roof, as a barrier preventing the formation of under-roof condensate. Widespread use in the device of hydro- and vapor barrier in the construction of buildings and structures. Protection of wooden structures. The material is largely resistant to negative atmospheric phenomena.

Izospan D is often used at construction sites as a temporary roof covering and installation of a protective wall in facilities under construction. Such a roof or wall can last up to four months. Type D is especially popular when constructing concrete floors that need a waterproofing layer that protects against earth moisture.

Application

1. In non-insulated roofs as a protection for wooden structures;
2. As protection against under-roof condensate;
3. Protection from negative atmospheric phenomena;
4. In the arrangement of basement floors;
5. Installation of concrete floors.

If there is a task to keep the internal parts of the dwelling from the influence of vapors generated as a result of the life of the activity, and to extend the life of the insulation, then the right decision would be to use the vapor barrier option with the letter “D”. Recently, more and more owners of country houses understand the importance of the role played by vapor barrier materials, the ever-growing demand is a strong confirmation of this.

Izospan D is spread directly on the rafters directly on the insulated surface of the pitched roof. In this case, the layers of material are the same and you don’t have to be puzzled which side to lay Izospan to the insulation. Installation is carried out horizontally, overlapping, rolls are cut into sheets of the desired size quite easily.

Work is carried out from the lower element of the roof and gradually follows in the direction to the top. Joints, in the process of laying, are glued with SL tape like double-sided tape. Adhesive on both sides, the surface connects two sheets of vapor - waterproofing. The wall-mounted isospan is fixed to the rafters with wooden slats or staples of a construction stapler.

Summing up our review, it remains to add that the manufacturer produces 14 types of such rolled insulation. We have considered only four main types. The buyer, guided by the characteristics of different types, always has the opportunity to buy isospan exactly for their needs. In addition, the manufacturer does not stand still and constantly expands the range of products, for example, there is a version of the film with flame retardant additives.

From our review it can be seen that working with the material does not require complex special skills and is within the power of almost any man. Ease of use and low installation costs make this building material a wide range of uses. The vapor barrier material will fully take over the functions that will ensure the reliability and long service life of your home and industrial thermal insulation.

Izospan is a group of vapor barrier materials. This is a coating that is used to protect existing barriers - insulation layers, if you skip the stage of vapor barrier flooring, the materials inside the heat-insulating "pie" will lose their properties. The reason for this is moisture. It will accumulate inside if there is no additional layer capable of passing steam through itself, which tends to leave the room. These processes are explained by the presence of a dew point in many building envelopes.

Isospan types

The material is offered in different versions, different in structure, purpose, parameters, effect during installation. There are several groups:

1. Vapor barrier film with hydro and wind protection function. This is a universal material that can protect the structure from most adverse external factors: moisture, wind outside; condensation inside. The isospan vapor barrier acts only in one direction: it allows moisture to pass from the room, but prevents the penetration of precipitation and wind from the street. For this reason, the material is called a waterproofing windproof vapor permeable membrane. This group includes coatings of type A.
2. Waterproofing vapor barrier. The material of this type does not protect from the wind, but does a good job of protecting the structure from moisture that can penetrate from the outside, and also prevents the formation of condensate. This group includes the following types of coatings: B, C, D.

The main technical characteristics of the vapor barrier:

• material density;
• breaking load - allows you to determine the limit of stability of the coating under the influence of tensile force;
• vapor permeability;
• water resistance.

Isospan A

This is a membrane material. It is intended for laying on frame walls, for the purpose of external insulation, during the installation of ventilated facades. They have a vapor barrier of this type from the side of the street, that is, at the last stage of fixing the thermal insulation before finishing work on the roof, outer walls. Options:

• water resistance - 250 mm Hg. Art.;
• vapor permeability index - more than 1000 g / m² / day;
• strength in longitudinal / transverse tension, respectively: 177 and 129 N / 5 cm;
• coating density - 110 g/m².

On the outside, the membrane is smooth, on the inside - porous. When using this vapor barrier, follow the recommendations:

• if roofing is being done, group A coating is only suitable for structures with a roof slope of at least 35 °;
• in order for the membrane to perform its function, it is recommended to leave a gap, such a measure will facilitate the removal of steam.

Izospan V

This is a double layer membrane. It is characterized by a lower density than the analogue of group A, but it is characterized by increased moisture resistance. This type of vapor barrier is used to protect surfaces of various types. Scope: bearing walls and internal partitions; attic, interfloor and basement ceilings; slope protection.

The membrane is also characterized by a specific structure, like the analogue from group A. Vapor barrier B is a two-sided material: on the one hand, the membrane is smooth, on the other - rough. Options:

• density - 70 g/m²;
• strength in longitudinal / transverse tension, respectively: 128 and 104 N / 5 cm;
• vapor permeability resistance - 7 m*hPa/mg;
• water resistance - 1000 mm Hg. Art.

Installation subtleties:

• the smooth surface should be inside (from the side of the room), the rough side of the membrane should be placed outside;
• there should be a gap between the vapor barrier layer and the finish - leave 5 cm.

Izospan C

This is a two-layer membrane, in structure it is similar to the material from group B, but differs in parameters. Vapor barrier C is characterized by increased strength, which contributes to an increase in the service life of the coating due to wear resistance. The material is used inside and outside the object: during the installation of wall insulation, partitions, including roof finishing. Characteristics:

• density - 90 g/m²;
• strength in longitudinal / transverse tension, respectively: 197 and 119 N / 5 cm;
• vapor permeability resistance - 7 m*hPa/mg;
• water resistance - more than 1000 mm Hg. Art.

Izospan D

This is a two-layer woven vapor barrier. It is characterized by increased strength properties, therefore it is used in difficult areas where it is subjected to significant loads: roofing, basement, concrete and earth floor. The coating withstands the pressure of a layer of snow, therefore it is often used as a temporary covering material when installing a roof.

Characteristics:

• density - 105 g/m²;
• strength in longitudinal / transverse tension, respectively: 1068 and 890 N / 5 cm;
• water resistance - more than 1000 mm Hg. Art.;
• vapor permeability resistance - 7 m*chPa/mg.

The material of this group almost does not stretch, while remaining strong, does not lose its properties.

Other types of vapor barrier

Coatings come in many varieties. The main options are discussed above, but there are also materials that are used less often due to the specific structure and properties:

1. Vapor barrier isospan AM. Represents group A. This is a three-layer membrane that does not require an air gap. It is characterized by strength in longitudinal / transverse tension, respectively: 160 and 100 N / 5 cm. Vapor permeability - at least 880 g / m² / day. Scope: attics, ventilated facades, external insulation, frame walls, protection of insulated roofs.
2. AS. This is another subtype of vapor barrier from group A. It is a three-layer membrane with a tensile strength in longitudinal and transverse tension of 190 and 110 N / 5 cm. Vapor permeability - 880 g / m² / day. The scope of this material is the same as that of the AM coating.
3. Vapor barrier A with OZD. This is a fire-resistant material, it is used in areas where welding is carried out during the installation of the insulation layer or a blowtorch is used. The main direction of application is ventilated facades. Vapor permeability - 1800 g / m² / day.
4. AQ proff is a three-layer membrane with enhanced waterproofing properties. Vapor permeability - 1000 g / m² / day. Scope: external thermal insulation, frame walls, attics, ventilated facades, pitched roofs.
5. Vapor barrier RS, RM. These are high-strength materials characterized by increased tensile strength in longitudinal and transverse tension: 413/168 (for RS coating), 199/172 (for RM). Vapor permeability - more than 1000 g / m² / day. According to the structure, the vapor barrier of these types is a three-layer material reinforced with a polypropylene mesh.
6. DM coating. This is a woven cover. Differs in high density. The vapor permeability of the material is more than 1000 g / m² / day. It can be used when arranging different surfaces: walls, floors, floors, made of any materials.
7. A separate group is a reflective vapor barrier with an energy saving function. The coating is characterized by the main properties: it passes steam from the inside out, protects against moisture, but also reflects infrared radiation in the room. Options: FB (kraft paper with lavsan), FD (polypropylene woven cover), FS (polypropylene non-woven cover), FX (polyethylene foam with metallized lavsan film).

The price of vapor barrier materials

The cost of coating varies between 1000-4000 rubles per roll (width 1.6 m, length 43.75 m). The price is formed taking into account a number of parameters: density, water resistance, vapor barrier indicators, tensile strength. The cheapest coatings of groups A, B, C, D. Two- and three-layer films of subtypes AS, AM, etc. will cost more. The most expensive material is AQ proff, due to its increased strength properties, versatility, high density, and excellent vapor permeability and water resistance.

Mounting Features

When performing work on insulation and vapor barrier, it is important to follow the sequence. Violation of technology will lead to deterioration and even loss of material properties. Izospan vapor barrier is mounted taking into account a number of features:

• the coating is overlapped (15 cm);
• along the perimeter, the material is fixed with a stapler, the membrane strips are interconnected with metallized tape;
• if heat-reflecting types of vapor barrier are used, the metallized side must be located inside the object.

Izospan vapor barrier: instructions for use

Installation sequence:

1. Determine the method of covering the floor. Depending on the type of vapor barrier and the surface that is insulated, the position of the smooth and rough surface of the membrane is selected.
2. The coating is laid on the wall, roof, floor.
3. Then proceed to the installation of the crate.
4. The finish is attached.

Preparatory stage

The insulated structure must be treated with special compounds that will ensure the protection of materials. For wood - flame retardants, antiseptics. For concrete - only antiseptics. Due to this, the likelihood of fungus or mold on the surfaces is reduced. Given that heat and vapor barrier structures are exposed to humid air, processing wood or concrete is a must.

Vapor barrier installation

When arranging the floor, the coating is laid directly on the rough base. The need to create a leak arises when installing a vapor barrier on a wall, roof, ceiling. Only in this case, the gap should be between the coating and the finish sheathing. For this, bars with a size of 40-50 mm are used.

The vapor barrier strips must be fixed to each other, otherwise moisture will penetrate through the leaks from the outside. Start work on finishing the walls and roof should be from the bottom. The material cannot be stretched. When the crate over the vapor barrier is ready, the finishing sheathing is attached to it.

How to install vapor barrier on the ceiling

To finish the interior surfaces in the room, a highly specialized coating is used, which performs only one function - it allows steam to pass through, protecting the thermal insulation. Such materials should not simultaneously be a waterproofing and a wind barrier. For internal structures, these functions are not needed. The principle of installing a vapor barrier on the ceiling:

• covering is laid;
• a crate is mounted, providing a gap of 5 cm;
• ceiling finishing.

Mounting on a cold pitched roof

Material type D or DM is used. In this case, a waterproofing coating is not used, but you can immediately proceed to the vapor barrier flooring. The membrane is fixed directly on top of the rafters with a stapler and metallized tape. Then a crate is installed, providing a gap for the effective operation of the vapor barrier. The cladding is attached to the top.

Very often I encounter gross violations during insulation using basalt insulation and mineral wool.

The main violations fall on improper installation and illiterate use of such a component as vapor barrier.

In this article I will talk about the types of vapor barrier and its application. I will try to pay attention to the "subtleties" during installation.

There are four types of vapor barrier: "A", "B", "C" and "D". Recently, the options “B, C, D” or “C, D, E” have begun to appear on the market; what it is and why it is needed, no one could explain. Therefore, let's exclude these options as potential, most likely, this is just another marketing ploy, though not understandable to anyone except those who came up with it.

Why is vapor barrier needed? …. Yes, it's very simple, as the name suggests. - remove fumes!

As mentioned above, there are four main types of this material.

The principle of operation is very simple: the material passes wet vapors only in one direction and, depending on the brand, has a different degree of this very transmission.

I will not go into the "subtleties" and parameters of each type - it does not make sense.

The classification is built in such a way that the farther the letter in the alphabet from "A", the less moisture the material passes through.

It seems not clear why this is necessary ?!

Soon everything will become clear as daylight!)

The figure below shows the "pie" of insulation in two layers of insulation and three layers of vapor barrier.

The principle of operation is as follows:

The steam leaving the wall passes through the first layer "C" without condensing on the wall. The size of the through hole in this layer of vapor barrier will be assumed conditionally equal to 1.

Thus, evaporation occurs faster than saturation with moisture, and provides stable physical properties of this insulation layer.

With the second layer of insulation and vapor barrier "A" (conditional through hole 3), everything happens in a similar way.

Except that at the exit of layer "A" the steam condenses and flows down. This point must be taken into account when installing the vapor barrier, mounting it so that the top layer overlaps the bottom one from the outside!

If you apply three layers of insulation, then another layer "D" is added and it is located before the layer "C".

If, for any reason, more layers need to be made, then on all first layers a “D” type vapor barrier or waterproofing is applied instead of the first layer of vapor barrier.

The same rules must be followed when warming the balcony and loggia.

A similar cake is used for roof insulation. With the only remark that during the installation of the metal tile, another layer of waterproofing is used, which is laid directly under the metal tile. At the same time, a gap of at least 50 mm is left between this waterproofing and layer “A” to ventilate the condensate!

Speaking of condensation! It happens a lot. Therefore, an unhindered flow should be provided for it!

Well, basically, that's all. Follow these simple rules, and your house will be dry and warm!

Izospan is a film-type insulating material. It ensures the preservation of the original qualities of thermal insulation and is used in a variety of fields. Therefore, it is worth considering in detail its advantages and disadvantages, as well as learning how to properly mount the material on the walls, roof, foundation. This and much more will be discussed later.

Types and their properties

Thermal insulation keeps the heat in the house when it is cold, adds comfort in the heat, and prevents the rooms from blowing through. However, the thermal insulation material itself needs protection from negative atmospheric phenomena. Such protection is provided by a polypropylene membrane - Izospan.

Such a canvas will successfully play the role of protection for thermal insulation. Despite its simplicity, this film material has differences: type A, type B, type C, type F, others. Each type has differences in technical characteristics.

The film complies with construction GOST and has the following generalized qualities, which are confirmed by the manufacturer:

• thermal conductivity;
• density;
• water resistance;
• elasticity;
• resistance to negative impact;
• resistance to ultraviolet;
• environmental Safety;
• Fire safety.

The properties of Izospan correspond to the classification of products. Classification - these are the letter indices with which manufacturers designate the produced material. Sometimes on sold samples you can see a combination of letter indices. Each new designation expands the possibilities of using the material. The performance of any Izospan is high.

The material is widely used in the construction industry. It is used for vapor barrier of both residential and industrial buildings. The properties of Izospan correspond to sanitary and epidemiological standards. The material is provided with certificates of conformity to fire safety and technical certificates.

In the production of Izospan, polypropylene is used. The base is melted down and then rolled out to a certain thickness with special rollers. The material is obtained homogeneous structure, dense. The material is considered two-sided, and both surfaces of Izospan perform different functions.

If you lay the vapor barrier correctly, all the moisture will remain on the film, it will condense on it. Being on the film, the moisture will evaporate and will not harm the structures.

Today, Izospan has gained recognition as an effective insulation material for attics, garages, walls of private houses.

The properties of the material will protect the metal coating from corrosion, and the wood from decay. The material prevents the penetration of air currents, does not release heat to the outside. When choosing products, you should focus on the quality of the main modifications, each of which has its own characteristics.

• Isospan A plays the role of an excellent waterproofing agent. This modification also protects the insulation well from wind and water, thereby increasing its service life. Izospan A is suitable as an insulator for any premises, as it is resistant to mechanical stress, neutral to mold and fungi. The film is stretched longitudinally by 19 cm, and across by 14 cm. The material is used as an additional barrier, fixed to the outer side of the insulation. For fastening the membrane, wooden slats and nails are used.

• Izospan V- an excellent vapor barrier that will eliminate high humidity indoors. Two-layer Izospan V can be used on roofs, internal and external walls, on attic floors. The material is stretched longitudinally by 13 cm, and across by 10.7 cm. Unlike the previous modification, Isospan V is installed inside the insulation, overlapped, taking into account the presence of free space between the layers.
• Izospan C- two-layer, known as a good protection for roofing, frame walls, as well as concrete floors. The membrane is fixed on the insulation, overlapped, with wooden slats. To insulate the floor, it is laid directly on the surface.
• Izospan D- very durable, known as roof protection in terms of waterproofing. In addition to roofs, Izospan D covers concrete floors at the level of basement ceilings. The material is mounted in horizontal stripes, fixed with wooden slats. In addition to the main modifications, there are additional varieties of Izospan, the purpose of which is worth considering in more detail.

purpose

The variety of materials of the Izospan line is wide. In addition to the basic materials, related products can be found on sale, namely, adhesive tapes and adhesive tapes.

• If the connecting tape SL fix the strips of hydro- and vapor barrier between themselves, the best impermeability of the connecting seams will be ensured. Installation with a connecting tape is carried out at a moderate temperature, and the surfaces to be joined must be dry and clean.
• Tape FL you can connect the canvases, and repair minor damage. This is a metallized tape with excellent durability. The wear and tear strength of this belt is also high.

• Unilateral adhesive tape ML characterized by good adhesion. The Proff modification material has shown itself in particularly difficult cases, as it helps in connecting uneven surfaces, different bases, for example, brick with concrete, porous surfaces. Izospan ML allows you to glue together plywood, wood and plaster surfaces. The material provides a better connection of pipes, windows to window openings.
• Izospan KL allows you to glue two panels together. Seals material overlap points well. Izospan KL is glued to the upper edge of the insulated panel, paper side up. It is pressed against the lower canvas with a slight movement of the hand at a certain distance from the edge. Then the paper side is removed from the tape and both edges are pressed against each other. The installation of the material is carried out on clean, dry canvases at a positive ambient temperature. The basis of the adhesive layer is a water-dispersion modified acrylic. Izospan KL does not contain solvents.

Waterproofing is applied according to general instructions for ceilings, walls, subfloors.

The work associated with laying the membrane is simple and does not require special qualifications.

• Regardless of the place of installation, the smooth surface of the film must always face the thermal insulation. Incorrectly laid canvases will not add efficiency to insulation, the structure will not receive the effect of vapor barrier. Each type of product is accompanied by instructions. Its exact observance will not allow you to make mistakes in your work.

• Lay the material close to the surface with a small spade in the corners. Place the canvases overlapping, the size of which should be about 15 cm. If the membrane is attached to wood components, you can use a furniture or construction stapler. Seal the resulting seams with tape or tape.
• If a reflective film is mounted, then it must be installed with the metallized side inside the room. Laying must be done without overlap, end-to-end. Glue the joints with adhesive tape.
• If you are performing a vapor barrier on an insulated roof, then lay the film from below. Lay the appropriate canvas horizontally, close to the rafters, avoiding windage. Wooden, antiseptic-treated slats 4 x 5 cm wide are suitable as film retainers. Such a crate will provide free evaporation of condensate.

The general view of the system will be as follows:

• interior decoration;
• Izospan B, C;
• rafters;
• insulation;
• waterproof membrane;
• roof covering.

Vapor barrier of the internal partitions of the house is needed if the interior ceilings are framed.

In this case, Izospan V can be installed on either side of the wall. A stapler or special nails are used for work. Izospan must be laid horizontally, starting from the bottom. Izospan is fixed with rails, and Izospan A can be mounted on the other side of the wall. General form:

• finishing;
• rail;
• vapor barrier;
• frame;
• insulation;
• moisture protection;
• rail;
• finishing.

Izospan can be used as a vapor barrier between floors.

The material is laid on the rough base of the ceiling with the rough side down. If the membrane is spread on the floor joists, above the insulating layer, then the smooth surface must be laid upwards. Clearances needed:

1. Between the insulation layer and the vapor barrier layer.
2. Between flooring and vapor barrier.
3. Between the ceiling finish and Izospan.

General form:

• ceiling finish;
• slats;
• vapor barrier;
• draft floor construction;
• beams;
• insulation;
• vapor barrier;
• slats;
• floor finish.

Like any building material, Izospan has its pros and cons. We will analyze in more detail the technical advantages and disadvantages, as well as consumer reviews.

Pros and cons

The main advantages of the material:

• Lasting. Izospan does not tear during installation, has a long service life.
• Reliable. When laying the material, other materials will remain dry in the most adverse conditions.
• Universal . It is possible to apply material on any types of designs at installation of any heaters.
• Environmentally friendly. The film does not emit harmful substances into the atmosphere.
• Practical.
• Fireproof.
• Convenient in installation.

Izospan perfectly weathers the accumulated condensate, significantly improving the performance of the insulation. The walls remain dry, so fungus and mold do not appear on them.

Of the minuses of Izospan, it is worth noting the need for mandatory treatment of wooden structures with antiseptic agents.

There are other disadvantages:

• in case of violation of the insulation technology, condensation may form at the joints of the material;
• vapor barrier rolls cannot be mounted immediately, you need to keep them in a warm room;
• the vapor barrier process is not possible if phenomena such as fog or rain are observed;
• when installing Izospan on the concrete surface of the basement, it is recommended to warm the latter with heat guns.

Consumer reviews of the material are generally positive.

• For example, users write about the qualities of Izospan C that work with it can be carried out simultaneously with the laying of the cake. The material allows you to save on the installation of the crate. The thermal insulation is in good condition after two years. There is no heat loss or damp spots.

• Another user notes characteristics of Izospan AS. Of the advantages, there is a high speed of installation. The material also has disadvantages - it is thin, the canvas is torn during fixation to the frame. In addition, it is difficult to determine the correct laying side for this type of material, since both of them are smooth.
• In contrast to this, FB series variant easier to define. Users note the good roughness of the correct reflective side. However, the material is expensive, since its width is non-standard. Investments justify themselves in further operation.
• Sides of Izospan B are also easily identified. The smooth side of the material must be mounted to the insulation. The vapor permeability of the material is at a height, the cost is fully justified.

Features of use

The sides differ in appearance, to the touch: one is smooth, the other is rough. It is believed that Izospan should be laid with the smooth side to the insulation. The rough side of the film should touch the insulated vertical. Roughnesses of Izospan effectively absorb condensate. Without a vapor barrier, condensate will always flow down to the floor structures. Condensation damages both wood and concrete substrates. Let's consider some special types of Izospan vapor barrier in more detail.

Vapor barrier series FB used in interfloor wooden floors, for walls inside the steam room, saunas. The FB series is based on kraft paper and metallized lavsan. Features of the structured Izospan allow you to effectively reflect thermal energy. It is not necessary to fasten the FB series outside, since the material perfectly resists the temperature environment with dry steam up to 140 degrees.

The strength characteristics of the material are excellent, it is environmentally friendly.

The use of Izospan allows you to reduce heat losses in the steam room. The same vapor barrier will prevent dampness inside the wall structure.

Izospan FB roll dimensions:

• width - 1.2 m;
• length - 35 m.

The material can be used in the temperature range from -60 ... +140 degrees. The technical characteristics of the material correspond to GOST. Performance may be reduced by exposure to UV radiation.

Materials of series have similar characteristics: FD, FS, FX. These are vapor-permeable membranes that prevent water vapor from escaping into the atmosphere. The materials are water-resistant, hydro-resistant, have an energy-saving effect. Materials are able to reflect infrared thermal radiation, protect floors from steam. The use of vapor barrier allows you to reduce the period of warming up the room, gives significant savings on heating the room.

Izospan AS series it is at the same time, waterproofing, vapor barrier, vteroizaschita. The membrane has three layers, protects against gusts of wind, moisture from the external environment insulation, roofing elements, walls. Izospan of the AS series can be mounted on a heater without a ventilation gap. As a result of applying a series of waste on the crate between the insulation and Izospan are excluded.

The diffusion membrane showed good water resistance and hydrostability. The use of this film has a positive effect on increasing the service life of the entire structure.

The material is produced in rolls 1.6 m wide, 70 m long. The effects of UV radiation, as in the previous version, reduce the quality characteristics of the material. Initial technical qualities correspond to GOST.

The AM series membrane has similar performance. The material combines the characteristics of water resistance and vapor barrier.

The scope is quite wide:

• insulated sloping roofs;
• frame type walls;
• walls with external insulation;
• ventilated facade;
• attic floor;
• inner verticals.

Separately, for ventilated facades, a series A film with OZD can be used. This vapor-permeable membrane will protect the elements of the facade from wind and precipitation. The film will not allow the removal of vapors from any type of insulating material. Film width 1.6 m, roll length 70 m.

Separately, the material of the RS series can be used as a roof vapor barrier. The film is suitable for non-insulated structures. It will protect wooden elements from the action of condensate, from penetrating atmospheric phenomena. As a vapor barrier suitable for flat roof structures.

Another type of film that is suitable for non-insulated roofs is Izospan RM. Three-layer material with reinforced polypropylene mesh. In addition to protecting roof structures, it can be used to protect floor concrete floors. In this case, it participates as a waterproofing layer.

Which to choose?

If the material is selected as a vapor barrier for the roof, then points such as:

• temperature phenomena at the location of the building;
• the purpose of the roof (exploited, non-exploited);
• roofing construction.

The vapor barrier layer, first of all, must be completely sealed. This quality is very important for such materials. Self-adhesive joint tape or adhesive tape is not in vain recommended for sealing seams.

If a vapor barrier is chosen for a bath, it is desirable to minimize the possibility of fire, so FD, FX, FL Termo, foil vapor barrier are the most suitable options for such structures.

It is important to consider that the bottom layer of the roofing cake must be non-combustible. The incombustibility of the bath roof will be increased if the vapor barrier film is laid so that its edges extend beyond the insulation. Experts advise gluing the membrane to the wall and additionally fixing it with galvanized strips.

Unlike roofing material and glassine, Izospan is a modern material of a new generation. The diffusion film has lower vapor permeability compared to the membrane considered in this article: it can be used for both hard and soft roofs.

Diffusion membranes usually consist of several layers. The product combines polypropylene fabric and polyethylene laminate. The cost of this type of vapor barrier is quite high.

However, other analogues have advantages and disadvantages. For example, types such as ruberoid and glassine, have a low cost. However, today few people will use roofing material for vapor barrier of the roof of a residential building. This is an economic material. Glassine is also not used as the main hydro and vapor barrier.

The application rate of bituminous membranes is also low. With the help of this material, concrete roofs are vapor-proofed. This type is mounted by heating and subsequent gluing to the base. The main disadvantage of the material is a lot of weight.

Almost all of the above types of materials combines Izospan, which is represented on the market by 14 varieties. The A class of Isospan alone combines several film options, for example, AS, AM, with different strength, density and vapor transmission ability.

RS series Isospan is a unique, versatile product that will completely replace all materials in the aggregate. The material is indispensable in many construction areas, as it has increased strength, does not harm interior decoration. Sealing reinforcing mesh made of polypropylene will not allow the formation of harmful fungi and mold, as it creates an additional protective layer for both the material and structures.

Length, thickness, weight, number of meters per roll varies depending on the class of the material. The division looks like this:

First grade

Isospan A

• width, m - 1.6
• size, m² - 35, 70

Second class

Izospan V

• width, m - 1.6
• size, m² - 35, 70

Izospan C

• width, m - 1.6
• size, m² - 35, 70

Izospan D

• width, m - 1.6
• size, m² - 35, 70

Izospan DM

• width, m - 1.6
• size, m² - 70

Third class

Izospan FS

• width, m - 1.2
• size, m² - 70

• width, m - 1.2
• size, m² - 35

• width, m - 1.2
• size, m² - 70

• release:
• width, m - 1.2
• size, m² - 36

In general, the indicators of various manufacturers are the same. Let's talk about the most famous suppliers of this building material and user reviews in more detail.

Famous manufacturers and reviews

Positive feedback is received by the following manufacturers of vapor barrier films that can be installed from inside the premises:

1. Ondutis;
2. Izospan V;
3. Izospan D;
4. Delta Reflex;
5. Delta Luxx;
6. Tyvek AirGuardSD5;
7. Tyvek AirGuard Reflective;
8. Stroybond V;
9. Isobond V.

Well-known manufacturers of waterproofing, which are also characterized on the positive side and have become widespread as a temporary roof:

1. Ondutis RV;
2. Ondutis RS;
3. Izospan D;
4. Stroybond D;
5. Isobond D.

1. Ondutis a100;
2. Ondutis a120;
3. Isospan A;
4. Isospan AM;
5. Izospan AS;
6. Delta Vent N;
7. Tyvek soft;
8. Tyvek Solid;
9. Stroibond A.

It is widely believed that the properties of hydro-vapor barrier films are better than those of simple vapor barrier materials. Users note the durability of Italian reflective films.

Laying method

1. It is necessary to lay any vapor barrier on any type of roof after laying the insulation. It can be placed under the corrugated board.
2. Waterproofing can be laid in any direction.
3. If the material is laid along the rafters, the overlap should be directly at the level of the rafters. At the same points of contact, the material must be carefully fixed.
4. At points of contact with water pipes that may pass through the roof, the membrane is wrapped down, wrapped around the pipes and carefully sealed with tape.
5. Some types of materials require a mandatory air gap. To create this space, thin wooden planks are enough. They are located at a distance of about 50 cm from each other.

The general rules for mounting the film require strict adherence to the instructions for use. Laying technology on vertical and inclined surfaces should be done from top to bottom. Lay the strips of film correctly horizontally. Lay the film with an overlap of at least 15 cm. For reliability, glue the joints with adhesive tape. If the wall is finished with drywall, the film must be laid with the rough side to the drywall, and the smooth side to the insulation.

• When laying a vapor barrier on the roof Izospan can be fixed directly on the rafters. For fixing, bars or thin clamping strips are suitable. Finishing: drywall, plywood, lining, etc., mounted on top of the vapor barrier. If bars were used for fixing, then the trim can be mounted directly on them. A gap is formed between the film and the finish. The ventilation gap will ensure better drying of the condensate.
• If Izospan used for indoor wall insulation, then first you need to fix the bars on the vertical. If drywall is used as a finishing sheathing, then a metal frame will do. After that, a heater is mounted: mineral wool or expanded polystyrene. A vapor barrier is attached to the bars with slats or a stapler. The next step is to install the finish.

• If the walls are insulated from the outside, the procedure should be reversed. First you need a crate of bars. Then a vapor barrier is attached to this structure. Next comes the heat insulator, and on top of it - a waterproofing film. The final step will be the installation of a fine finish.
• If a vapor barrier is used for the floor, first, waterproofing must be laid between the lags. Then the heater is installed. A vapor barrier is mounted on top of the insulation. Bars are suitable for its fastening. Floorboards are installed on top of the vapor barrier.
• When installing an interfloor ceiling the previous steps are practically repeated. If necessary, a vapor barrier can also be installed on the ceiling from below. The ceiling trim is mounted on top of the vapor barrier.

• ​​​​​​If the vapor barrier is damaged during installation about any structural elements, torn places must be repaired. To do this, you can use adhesive tapes or special glue. The material is very reliable in installation and more expensive than conventional polyethylene film. However, the quality characteristics of Isospan significantly exceed the quality of the film.

The following tips will help you get the job done right.

1. When laying any vapor barrier materials, monitor the quality of the joints. If they are poorly glued, the ceiling usually sweats, and the efforts from the work done are practically reduced to zero.
2. It is easiest to close any hole in the membrane with a special tape for sizing at least 10 cm wide. A narrower tape will simply peel off.
3. Leave folds of material 2-3 cm wide around windows, other openings, especially if the building is new, built. Deformation stock in this case should be provided necessarily.
4. If a vapor barrier membrane is installed around skylights, it must be protected from the inside with a special finish.
5. If the membrane needs to be fixed on a rough surface of brickwork, wood, it is better to use adhesives with an acrylic or rubber base.
6. Adhesive tapes based on polyurethane are not recommended for use by specialists. It is believed that due to insufficient stickiness, they eventually move away from the base.

For the use of Izospan, see the following video.

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