Foil insulation for bath walls. Foil on a paper base for a bath

Among the many types of thermal insulation materials for arranging baths, consumers increasingly prefer aluminum foil. This simple and affordable coating retains heat well inside the building, preventing rapid cooling of the building, thereby reducing energy costs and ensuring a comfortable stay inside the bath.

Taking into account the peculiarities of the operation and microclimate of the bath room, a number of requirements are imposed on the used foil:

good moisture, steam and water resistance;
high refractory qualities;
good anti-corrosion properties;
high reflectivity (within 95-98%), achieved through special polishing of the top layer;
significant thermal conductivity.

Self-adhesive insulation with foil

Excellent vapor barrier properties help prevent hot steam from escaping from the room, which will not accumulate in the coating. In addition, aluminum foil has the following advantages:

complete absence of deformation and loss of original consumer properties;
high ductility of the coating upon prolonged exposure to high temperatures;
lack of emission of substances and vapors harmful to humans;
UV resistance;
protection against excessive condensation, mold and pathogenic microorganisms;
ease of installation;
durability;
hygiene;
resistance to chemicals;
protection of adjoining or adjoining rooms, if the bath is located inside the house.

With careful installation, even thin paper-backed sheets will not tear or deform. But it should be remembered that such material should be bought with a small margin of 5-7%.

Aluminum foil can withstand temperatures up to 145 ° C, which, combined with its high reflectivity, helps to keep the heat inside the steam room in comparison with other heaters for 2-2.5 hours longer, providing the so-called thermos effect. It is a universal insulation material suitable for walls, floors and ceilings of steam rooms, baths and saunas and does not require special treatment of premises with fungicidal substances.

Bath foil prices

bath foil

Foil types and coating features

The building materials market offers customers several types of foil with different properties and characteristics.

Cover type	Dignity	Application type	Application type
Folgoizolon (foil applied to polyethylene foam in rolls or polystyrene sheets)	High strength, shock-absorbing and sound-insulating properties, the ability to lay the material directly on the surface without additional thermal insulation.	Suitable for log walls, as well as surfaces with battens or clapboard.	The thickness of the material in sheets is from 20 to 100 mm, the dimensions of the canvas are: length -120 cm, width - 600 mm. The thickness of the roll material is from 20 to 110 mm, the standard length is 25 or 30 m, the roll width is 100 or 120 cm. The range of withstanding temperatures is from 100 to 125 ° C.
	Environmentally friendly material.	Foil material is used on any surfaces, but in combination with a heat-insulating coating.	The thickness of the sheets ranges from 0.03 to 1 mm, the temperature range is 50-85 ° C.
	High degree of vapor and moisture insulation.	Suitable for use on concrete and brick walls as well as all types of wood surfaces.	Thickness 8-10 mm, maximum withstand temperatures: from + 100 to +125 ° С.
	Good insulating properties and easy installation.	The same as for roll materials.	Similar to the previous ones.
	Low cost, accompanied by tears and deformation of the material during installation.	Only on refractory heat-insulating material with obligatory fastening with metal brackets.	The sheet thickness is 0.01-0.5 mm, the roll width is 1500 mm, the temperature range is from -50 to +75 ° C.

To obtain a high-quality coating during laying work, it is recommended to strictly adhere to the thickness of the foil insulation.

Wall material	Steam room wall thickness	Recommended layer of foil insulation
Brick, concrete	35-37 cm and more	8-10 mm
Brick, concrete	25-35 cm	10-12 mm
Wooden blockhouse	10-15 cm	6-8 mm
Wooden blockhouse	15-20 cm	4-6 mm
Wooden blockhouse	more than 20 cm	2-4 mm

Experts remind that aluminum foil or foil coatings are not able to reflect back inside the premises all the heat that has left, therefore they work best in steam rooms, insulated according to the "pie" principle, while basalt or glass wool, as well as similar ones, should be used as an additional heat-insulating material mineral heat insulators. This is especially true in baths and saunas built of brick or concrete and other frame structures. With a sufficient thickness of the external walls of wooden log cabins, additional thermal insulation can be neglected, but thin sheets of kraft foil should not be preferred as foil-clad material.

Coating installation

For the most effective and high-quality coating and to ensure a comfortable stay in the steam room, when laying the material, you should adhere to a number of tips.

When laying foil-clad materials in steam rooms of non-commercial baths and saunas, it is sufficient to use roll or craft foil with a thickness of at least 3 mm.
Foil on a mineral or basalt base is suitable for large steam rooms.
When placing a sauna inside a house or in a basement, it is important to take into account the central heating and the location of its sources, if possible using it for additional heating of the steam room air.
Before starting work, it is necessary to provide for condensate drainage by making a small withdrawal of the canvas from the ceiling to the walls, as well as from the walls to the floor. For this, the foil material is laid with an overlap of 15-20 cm and glued with foil tape.

Important! To create a "thermos" effect, a gap of 13-18 mm must be left between the foil layer and the finish to ensure ventilation and maintain a healthy microclimate.

Foil mounting process occurs in several stages, the most convenient to use are rolls or sheets 60 cm or 1.2 m wide.

On the walls of the steam room, you need to make a crate with beams with a section of 5x5 cm. The distance between adjacent strips depends on the width of the material. For rolls of 600 and 1200 mm, this is 60 cm, for foil materials with a width of 1000 mm and 1500 mm - 50 cm. The bars are fixed with self-tapping screws of a suitable length.
A layer of mineral insulation is laid between the planks so that it does not protrude beyond the level of the beams.

Fastening insulation plates to the ceiling. In the photo - the use of foil insulation
On top of the insulation layer, foil-clad material is fixed with the obligatory placement of a reflective layer inside the steam room. The joints of adjacent canvases or sheets can be glued with metal tape, but it should be remembered that the glue can soften under the influence of high temperatures, and the panels will disperse, breaking the tightness.

It is best to fix the foil with staples or nails, nailing them directly onto the beams. With a large width, the foil material is fixed not only at the edges, but also in the middle.
The laid foil is sewn up with clapboard, leaving a one and a half centimeter air pocket, the main function of which is to reduce the heat-conducting properties of the foil layer and to maximize the reflection of all rays that hit the foil back into the steam room. An air pocket will allow you to create a lathing under the lining. Choose strips with a thickness of 10-20 mm and fix them with self-tapping screws.

Sometimes the order of the arrangement of materials can be changed - a layer of foil is stuffed onto a layer of insulation placed between the battens of the lathing, staples or nails, which is fixed on top with thin slats, placed strictly on top of the lathing with self-tapping screws of sufficient length.

In some cases, it is allowed to stuff a wooden crate over a layer of insulation, laying foil over the entire area of the walls, incl. and on the uneven bars. Then it is impractical to leave air pockets, and the lining is fixed directly on the crate. But, as practice shows, the purchase of combined heat-insulating materials with a foil layer is not only economically more profitable, but also greatly simplifies the entire installation process.

Let's start with the fact that many do not know at all whether foil is needed for a bath. The question is relevant for most of the owners of country houses. If you believe the professionals, then the foil must be used when decorating the bath, since the inside requires a fairly high temperature, which, in addition, must also hold for a long time. It is for this reason that the ceiling and walls are covered with insulating material that prevents heat energy from escaping outside the room. In almost all cases, the "cake" that is formed on the inner surfaces of the bath for the purpose of insulation includes aluminum foil. The latter, in turn, is produced in several versions at once.

Be that as it may, we note that the foil recommended by some people for use in the bathhouse is categorically denied by others, and the dispute between the parties has not subsided for a long time. That is why we have to figure out whether the foil is really so necessary or can we refuse it? In parallel, we will find out what this material is, what it can be, how much it costs and how to properly perform the installation for maximum efficiency of the insulation layer.

And now, having familiarized yourself with the features and main varieties of the material described in the article, you can begin to consider some of the popular brands. For the convenience of visitors, the information below is presented in the form of a small pivot table.

The price of foil for warming a bath

Table. Popular foil heat insulators for a bath.

Name, photo	Characteristics, description	Average market value, in rubles
1. "Annealed" foil	A fairly soft material, the thickness of which is 100 microns. Sold in rolls of 10 square meters. As for the total length of one roll, it is equal to 10 meters. Complies with GOST.	From 1400 rub. (for one roll)
2. "Isover Sauna"	The aforementioned brand of insulation 5 centimeters thick is also sold in rolls 12.5 meters long. The total area of one roll is 15 square meters. It is characterized by the fact that it also has soundproofing properties.	From 2200 rub. (for one roll)
3. "PARK MAT ALUCOAT 35"	Quality Finnish heat insulator, still sold in rolls. The thickness of this material is 3 centimeters, and the length of one roll is only 8 meters. In addition, the total area of one roll of insulation is 7.2 square meters.	RUB 1800 (for one roll)
4. "Rockwool Sauna Butts"	And this is already foil mineral wool, which is sold in plates. The thickness of this material is 5 centimeters, and the dimensions of one slab are 60x100 centimeters (WxL). The total area of one slab is 0.6 square meters.	750 RUB per package (8 plates)
5. URSA GEO M-11F	High-quality roll insulation - foil-coated mineral wool. Characteristically, this bath foil lined with kraft paper. The thickness is 5 centimeters, and the length of one roll is 12.5 meters. The optimum operating temperature is +270 degrees.	RUB 2100 (for one roll)

As you can see, the cost of foil varies and depends not only on the variety, but also on the specific manufacturer.

Is a foil layer in a bath really needed?

As a rule, baths today are insulated with thin foil (thickness varies within 30-300 microns). Tellingly, the aluminum layer can either be applied directly to a heat insulator or kraft paper, or sold separately for later use in tandem with other insulation materials.

Those who are against the use of foil claim that there is no use for it, since its thermal conductivity is high enough, and therefore it is simply unable to retain heat inside the room. Opponents of this method believe that buying / installing a foil-clad thermal insulator is just a waste of money. Note that this is partly true, because the use of foil can only be effective if it is installed correctly.

That is why the room, during the decoration of which the foil for the bath was used, heats up faster and retains heat longer. Therefore, it would be quite logical to conclude that it will be more comfortable to take a steam bath in such a bath, while heating costs will noticeably decrease.

The main advantages of foil for a bath

In view of the operational and climatic features of the bath room, a number of requirements can be distinguished, which must be met by the used aluminum foil:

high moisture and vapor resistance;
adequate thermal conductivity;
fire resistance;
high reflectivity (from 95 to 98 percent), which is obtained due to the special polishing of the outer layer;
excellent anti-corrosion properties.

As we have already found out, high vapor barrier characteristics prevent the escape of heated steam from the room, while it will not accumulate in the coating.

In addition, aluminum foil for a bath has other advantages:

it does not deform and does not lose its original properties;
it protects adjacent premises, if any;
the material is plastic, even if it is exposed to high temperatures for a long time;
it is highly resistant to chemicals;
does not emit harmful gases and compounds;
hygienic, durable;
resistant to UV radiation;
extremely easy to install.

Note! If the foil is handled carefully, even the thinnest sheets will not tear and deform. But in any case, it is necessary to purchase the material with a small margin (at least 5 percent).

The maximum temperature that the foil can withstand can reach 145 degrees. Thanks to the creation of the so-called thermos effect, the heat remains inside for about 2.5 hours longer. We also note that the material can be used both for walls and for floors and ceilings (that is, it is universal), and does not need any special treatment with fungicides at all.

What to look for when choosing a foil for a bath?

If you intend to purchase a suitable foil, you must take into account several factors that affect the durability of the material, ease of installation, and future efficiency. Let's consider the main selection criteria in more detail.

Key varieties of foil heat insulators for baths

There are many types of foil, as well as combined insulation materials in which it is present, and they all differ not only in cost, but also in different characteristics. We will consider today only the most common of the materials.

Option number 1. Roll foil (no base)

This material is quite thin, and its strength can hardly be considered high. The thickness of such insulation can reach 0.2 millimeters, while the width varies between 100-150 centimeters. The material is sold, as you might guess from the name, in rolls 5-20 meters long. Used for wall mounting on top of an existing base thermal insulator. It must be fastened with an overlap, and the joints must be glued with metallized tape to obtain the most sealed reflective coating.

Note! The material can be used at a temperature of no more than +650 degrees, so the foil-trimmed steam room will quickly warm up and keep warm for a long time.

In addition, such foil is resistant to corrosive processes, and does not emit any toxic substances when heated.

Option number 2. Kraft foil

It is made with a paper base or, which is preferable, in a three-layer design (paper - foil - PE), also known as Izolan. The strength is quite high, the material can be laid on top of the timber without using an additional heat insulator (provided that the walls are well caulked). The material is environmentally friendly, its thickness can be up to 1 centimeter. It can be operated at a temperature of no more than +100 degrees. Installation requirements are the same as in the previous case, however, it is more convenient to work with such material, since it is more durable and does not wrinkle so much.

Option number 3. Folard

In this case, we are talking about a vapor barrier, which can consist of one / two layers of foil-clad material, as well as of a reinforcing fiberglass mesh (the cells of the latter are 4x4 millimeters). This kind of reinforcement allows the material to retain all its original characteristics even at temperatures from -60 to +300 degrees! This material is also environmentally friendly, capable of withstanding considerable loads (including of a mechanical nature). It is produced in several varieties. Sold in rolls 100 centimeters wide and 50 meters long.

Option number 4. Folgoizolon

The next, so to speak, foil for a bath is foamed PE with a foil coating. Sold in sheets / rolls, may have different thicknesses. A very durable material that can be installed without using the main insulation. It can be used not only for log walls (as the main heat insulator), but also for concrete / brick walls (as an auxiliary one). The maximum permissible operating temperature is about +125 degrees, the dimensions (WxDxT) are 60x120x2x11 centimeters. It is easy to cut the material, as well as mount it to the lathing, but at the same time it does not deform.

Option number 5. Foil mineral wool

The last type of foil that we will look at today. Sold in slabs and rolls, the thickness varies between 0.5-10 centimeters. The sizes can be different, and here a lot depends on the specific manufacturer. Excellent reflectivity - up to 97 percent, maximum permissible temperature - +300 degrees.

Note! There are many types of foil mineral wool, but one of the most popular (at least in Russia) is Isover Sauna, which has all the properties that the specifics of this room require.

Video - Heat insulators "Rockwool" for a bath

Key features of insulation: what you need to know?

Before proceeding directly to the insulation, you should learn about the rules for its implementation, as well as about what you should definitely pay attention to. So that the foil takes part in maintaining the required indoor climate, consider the following important points.

The room must have good ventilation. Otherwise, all the insulating layers will be saturated with moisture and lose their original characteristics. The foil-clad material itself will become simply useless.
There should be ventilation gaps between the finishing material and the insulation layers.
Fasten all layers correctly, in accordance with the requirements, also do not forget to seal the joints between the sheets.

Remember that if you do not fulfill at least one of the listed requirements, then, probably, all your efforts will be wasted, and the final thermal and sound insulation properties of the foil will be practically zero.

What should be the thickness of the thermal insulation in the bath?

Much depends on the thickness of the walls, as well as on the material from which they are made. So, for brick / concrete walls with a thickness of 25 to 35 centimeters, it is necessary to use a heat insulator with a thickness of 10-15 centimeters. For the same walls, but with a thickness of more than 35 centimeters - within 8-10 centimeters. If we are talking about wooden walls 10-15 centimeters thick, then the thickness of the heat insulator should be about 6-8 centimeters, if 15-20 - then about 4-6 centimeters, finally, if over 20 - then about 2-4 centimeters ... As you can see, there is nothing complicated here, so we go directly to the installation work.

Step-by-step instructions for warming a bath

To begin with, we note that if the steam room is small, then there will be enough foil in rolls or craft foil, the thickness of which is at least 0.3 centimeters. But if the steam room is quite large, then it is better to give preference to materials based on mineral wool. Also, be sure to think over how the condensate will be discharged: if the ceiling is insulated, then the foil from it must be taken out to the walls, and if the latter are insulated, then on the floor. In this case, the overlap should be about 15-20 centimeters, and all joints, we repeat, should be glued with metallized tape.

Note! Do not forget about the ventilation gap between the insulating layer and the finish (about 1.3-1.8 centimeters). In this case, you will achieve a healthy indoor climate.

The installation process itself does not represent anything complicated and consists of several simple steps. Let's consider the features of each of them in more detail.

Step one... First, build a crate on the walls using a 5x5 centimeters bar for it. As for the step of the lathing, in this case it depends on the width of the insulation. If it is 60-120 centimeters, then the step, respectively, should be 60 centimeters; for foil, the width of which is 100-150 centimeters, it is 50. For fixing the bars, use self-tapping screws of suitable length.

Step two... Place an insulating material between the battens of the sheathing. Try to do this in such a way that the heat insulator does not go beyond the level of the planks.

Step three... When the main insulation is installed, lay a foil covering on top of it, without fail placing the latter with a reflective layer inside the room. To seal the joints between the sheets, you can use metallized tape, but remember that the glue, being under prolonged exposure to high temperatures, softens, which means that the canvases may well disperse, which leads to a violation of the tightness of the entire coating.

It is desirable that bath foil fixed with nails or staples - the latter should be nailed directly to the bars. And if the width of the foil is large enough, then it should be fixed both at the edges and in the center.

Step four... Sheathe the fixed foil with clapboard, while not forgetting about the air gap 1.5 centimeters thick. This layer is necessary in order to reduce the thermal conductivity of the foil in order to limit the reflection of all rays that hit the coating back into the room. Getting this kind of air "pocket" is possible thanks to the construction of a wooden lathing under the lining. For this lathing, try to use bars, the thickness of which is within 1-2 centimeters, and for fixing use all the same screws.

Sometimes the crate can be built on top of the insulating layer - in this case, the foil will be filled immediately over the entire area of the steam room, even on the beams. If so, then there is no particular need to create air "pockets", and the lining can be fixed directly on the crate. However, practice shows that the use of combined materials, including a foil layer, is preferable not only in economic terms, but also because of the significant simplification of all installation work.

Video - Decorating a steam room in a bath

Thanks to the use of foil when decorating the steam room, you can save from 25 to 30 percent on fuel for the stove, in addition, the service life of the entire structure will noticeably increase, as you prevent the development of mold, fungi and all kinds of microorganisms that are harmful to health ...

Video - How to sheathe a steam room in a bath with foil

Features of bath ventilation

As noted earlier, the arrangement of a high-quality ventilation system is imperative for the normal functioning of the thermal insulation cake. This should be taken care of in advance - even before proceeding directly to the insulation. There are several layouts of ventilation holes at once, let's take a brief look at each of them.

The first

This is the circuit indicated in the illustration above with the letter "a". This is natural ventilation, the supply outlet for it is arranged at the bottom of the wall next to the heating device, and the exhaust outlet is located on top of the opposite one. The option is simple, but its effectiveness is poor. For example, some people open doors to increase ventilation.

The second

Option "b", in which both vents are located on the same wall, and the heater is located on the opposite one. Suitable for saunas with one outer wall. A fan (in the inlet) is used to strengthen the system.

The third

As for the "c" option, it must be implemented even during the construction of the bath, since the air in this case will move under the final floor. The location of the ventilation windows is the same as in version 1, but the fan should be placed already in the exhaust opening (the one on top). Quite an effective system, it is worth noting.

Fourth

Finally, the "g" scheme is effective only when the stove is fired. There is only one hole here - the supply one - and it is located on the wall opposite from the heater.

As a result, we note that the dimensions of the ventilation openings depend on the specific area of the room. So, for every square meter of the steam room there should be at least 24 square centimeters. That's all, good luck with your work!

Aluminum foil for baths and saunas has an optimal combination of qualities required for thermal insulation in this type of room. Keeping warm is the first priority for a high-quality steam room.

If the heat will easily leave the premises, then the following troubles await us:

Huge cost of trying to heat a rapidly cooling building.
Lack of proper relaxation and hot steam treatment.

Warming the bath with foil will help to avoid its transformation into an ordinary gazebo. In this article, we will consider the technical characteristics of this material and the stages of its installation.

Aluminium foil

It is important to know: aluminum has a high thermal conductivity and a high reflectivity. Therefore, heat is retained not by containing it, as when using other heaters, but by reflecting it back into the room.

For high-quality thermal insulation of the steam room, the insulation material must have increased water resistance and fire resistance.

Foil for baths and saunas is ideal for these parameters.

Specifications

There is no deformation effect at high temperatures.
Aluminum does not emit vapors harmful to humans.
High level of vapor barrier. Thanks to this, hot steam does not leave the room, but fulfills its purpose.

No steam accumulation in the material itself. This significantly increases the service life.
Acceptable price.
Condensation does not fall on the walls. This is especially important in the case of wooden walls. Since the presence of condensation can lead to mold and decay processes.
Isolation of the material from the harmful effects of excessive moisture and other possible effects. This extends the life of the building itself.
Heat reflection effect. The aluminum surface reflects thermal radiation, which significantly speeds up the heating of the steam room, which saves on heating costs.
Easy to install. Do-it-yourself affordable implementation.
Durability. Does not rust, rot, and is not attacked by pests.

This solid list of advantages generally applies to foil as a heater. But today the manufacturer offers different types with some features.

Views

What is the best foil for a bath?

Let's look at its most prominent representatives:

Folgoizolon for a bath is a polyethylene coated with aluminum foil. To all of the above qualities, a high level of sound insulation is added and increases strength. And heat preservation is carried out not only due to reflective properties, but also due to a decrease in thermal conductivity.

Foil on a paper basis for a bath significantly increases the strength and reliability of the product and is an environmentally friendly material.

Foil insulation for a bath is any classic insulation material, for example, isolon or even mineral wool, on which one side is covered with a layer of foil to increase waterproofing, fire safety and protection from the aggressive environment of the steam room. The cost accordingly increases depending on the combined insulation.

Thus, all varieties are simply to add an additional layer, which adds some quality, but also increases the cost. In order to save money, ordinary foil in the bath is suitable, so it has a sufficient number of the necessary qualities.

Installation

The following instructions will help you install the foil:

We buy a sufficient amount of foil with a thickness of 100 microns.
We fix the foil on the boards with a stapler, furniture nails or buttons. At the same time, we make gaps of several centimeters.
We fasten the aluminum tapes together with mounting tape.

Tip: Aluminum has a high electrical conductivity. Therefore, be sure to carefully insulate possible wiring in the bathhouse.

On top we install a crate made of wooden planks, which will serve both as a reinforcement for the foil layer and as a base for interior decoration.

We mount the inner finishing layer.

It should be noted that when using an additional insulating layer, it is installed in front of the foil.

For example, if it is mineral wool, then we do the following:

We nail wooden bars with a cross section of 5 cm by 5 cm on the walls and ceiling of the steam room. At the same time, the distance between them is equal to the width of the insulation plates.
We put insulating material between them.
This is followed by the above stages of installation with one clarification: the foil is fixed on the intermediate strips.

If you use insulation for a bath with foil, then the sheathing process is even more simplified and becomes economically more profitable than purchasing and installing them separately.

Output

It is necessary for their full functioning. The steam room, unable to keep warm, is nothing more than a comfortable gazebo. One of the most economical ways is to cover the inside of the walls and ceiling with a layer of foil.

At the same time, it should be understood that such a material does not work like most other heaters, which hold back the heat inside the room due to their low thermal conductivity. The aluminum coating allows it to reflect thermal radiation, due to which not only heat energy is saved, but also the process of heating the bath is faster.

The combination with classic insulating materials allows you to achieve an even higher effect. But at the same time it also increases the cost of the final work.

The video in this article will provide additional resources on the topic.

It will only bring you real pleasure and strengthen your health!

Despite the Internet controversy that has flared up for a long time over the use of foil to keep heat in the bath, the convictions of its supporters and opponents have not been shaken.

However, the point of dispute was initially the physical properties of the material, and nowadays there are enough funds to make "selection" - to enhance the required properties of the material and weaken the unnecessary ones.

Look at the bathhouse and the mode of its use as a combination of factors, each of which can be “for” or “against” insulation with this material. With this approach, harm and benefit cease to be absolute categories, as they are usually presented in disputes.

We will tell you how to properly lay the foil for optimal results, but this will be discussed in other articles.

This article is devoted to an examination of the materials available on the market; here both foil and foil-clad heater for a bath will be considered.

Foil for a bath: the pros and cons of using

The bathhouse, and even more so the steam room, are places with a very specific temperature regime and high humidity. Sauna foil is ideal for this environment because easily withstands large temperature drops.
Most lose their properties when wet, so it is customary to protect them with a layer of waterproofing. Thin aluminum quietly takes over this function, since metal does not absorb moisture.
Her high ability to reflect rays of the infrared range ensures the preservation of heat inside the bath and steam room.
Ease of installation makes the installation of foil insulation feasible even for a non-professional. Also, there is no need for special equipment.

The downside is that moisture that has not been absorbed by water accumulates on it in the form condensation, which can cause rotting of the finishing coating or the growth of fungi on it, but this is treated with a ventilation gap between the aluminum and the same clapboard.
High thermal conductivity of aluminum, from which it is made, would also be a big disadvantage if it were not compensated by a layer of insulation with low thermal conductivity following the metal.
Another disadvantage is foil corrosion., that is, the formation of an oxide film on its surface. Of course, such a film degrades the reflectivity. But the purity of the metal (absence of impurities) significantly slows down the oxidation of aluminum.
Well temperature + water hammer, but more on this below

When you need it and when not

It is not needed by those bathhouse owners for whom neither fuel economy nor long heating is a problem.

It is also not needed by those who completely deny its ability to reflect infrared radiation through the lining layer, but believe that the thermal conductivity of aluminum is the guarantor of rapid cooling of the bath with the help of foil.

There is no need for it even if the bath is sufficiently insulated using traditional methods, and its heating and cooling are completely satisfactory to the owner.

It is incorrect to believe that it will not find use in baths from it, since in wooden buildings only correct and high-quality sealing of all cracks is required. Any bath can be insulated if desired. Let it be a repetition, but foil is needed where time and effort are valued.

With it, heating occurs faster, and cooling is slower.

Useful video

However, despite the above, it is believed that the absence of foil makes vaping softer, eliminating a sharp water hammer during paired procedures:

Foil and insulation for baths with foil: types

View	Release form	Peculiarities	Dignity	disadvantages
Roll foil	rolls: thickness 0.007-0.2 mm width 1-1.5 m length - 5-20 m	the roll can have from 3 to 5 breaks inside, so take with a margin of 5-7%; any wall, but put the foil on the fireproof insulation	does not burn; does not emit toxins; holds up to +650 degrees; reflects up to 97% of infrared radiation.	easy to tear and wrinkle
Kraft foil	rolls reinforced with paper or paper and polyethylene. thickness - 0.03-1 mm	any surfaces, but you also need insulation	does not emit toxins; holds up to +100 degrees; stronger than baseless; reflects up to 95% of heat.	combustible
Foil fabric	fabric rolls with one-sided foil reinforcement, width - 1 m, length 25 m	similar to the previous	temperature range -50 +200; thermal reflection 97%; non-flammable; environmentally friendly material.
Folard	rolls in three types of release: "A" - two layers of foil, between them - fiberglass in the form of a mesh with 4x4 cells; "B" - one layer of foil and the same fiberglass "C" - foil, fiberglass, adhesive base. Roll width 1 m, length 50 m.		"A" temperature range -40 +300 very durable material; environmentally friendly - does not emit toxic substances when heated.
Folgoizolone	foamed polyethylene foil on one side. release form: sheets and rolls. sheet: length 120 cm, width 60 cm, thickness 2-11 cm. roll: length up to 30 m, width 1-1, 2 m, thickness 0.2-1 cm.	for walls and clapboard	holds 100-150 degrees; self-extinguishing when burning; thick sheets can be an independent insulation; low weight; high strength; low thermal conductivity.	combustible
Foil mineral wool	mats or rolls of mineral wool with one-sided foil; thickness varies from 0.5 to 10 cm, length and width depend on the manufacturer (there is no single one).	concrete, wood	temperature range -60 +300; reflectivity up to 97%; not flammable; high thermal insulation properties (thanks to mineral wool).
Foil basalt wool	insulation for baths with foil, a kind of mineral wool, the same release forms.	similar to the previous	properties - similar to the previous one, but basalt wool stores heat better; temperature range -200 +700 degrees.
Foil polystyrene foam	plates of extruded polystyrene foam with one-sided foil.		working temperatures -50 +75 degrees; with the addition of fire retardants - self-extinguishing in case of fire.	combustible; emits harmful substances;
Insulation for the bathhouse "Rockwool" with foil	stone wool slabs with foil on one side, dimensions 0.6x1 m, thickness 5 or 10 cm. Pack of 8 slabs.		holds up to +200 degrees; biostable; not flammable; durable; environmentally friendly.

It is worth noting that all of the listed types, everyone decides on their own, are excellent vapor barriers. They are not afraid of both mold and fungus. But this is for them, and the tree needs an antiseptic.

For the foil to work

The "thermos" you have created will work only if no mistakes were made during the installation process. Otherwise, you risk not only losing time and money, because the "wrong bath" can even harm your health. To prevent this from happening - read our articles on foil installation.

So, we examined the pros and cons of foil insulation, the use of foil, and you yourself decide whether you need foil insulation for a bath or it is better to pay attention to natural insulation, for example,.

An ideal sauna building should warm up as quickly as possible and retain thermal energy for a long time. For this, the walls and ceiling are insulated in it. A heat insulator such as aluminum foil for a bath is one of the most demanded materials, as it is resistant to high temperatures and humidity.

Foil properties

Among the characteristics that foil for baths and saunas has, the most important is the ability to reflect about 97% of infrared rays. If this material is used for continuous sheathing of the steam room, the thermal energy will be retained as much as possible. The fact is that the IR rays are not absorbed by the walls, but are reflected towards the room.

Foil for a steam room is ideal because:

the material is able to withstand temperatures up to 300 degrees and even higher - this property depends on its type;
does not emit substances harmful to the human body;
has a low specific gravity.

In addition, aluminum foil has the following advantages:

moisture resistance;
plasticity;
durability;
vapor tightness;
resistance to corrosive processes.

When using this material, almost all the heat remains in the steam room, while the insulation for the bath with foil on the walls will be reliably protected from condensation. The fastening process is simple, the main thing in the work is not to allow deformation, and not to leave gaps between the canvases.

To achieve a greater effect, foil heaters for a bath are sheathed not only on the walls, but also on the ceiling surface, since steam and hot air first of all rise up.

Roll aluminum foil

Foil is produced both in rolls and in sheets. Roll material can have a thickness of 0.007 to 0.2 millimeters, a width of 10-1500 millimeters. The percentage of aluminum in it is up to 99.5%.

Depending on the type of surface, foil is:

smooth, without additional finishing;
for finishing;
finishing.

According to the scope of application, the material is divided into a canvas:

food;
technical;
tape.

Depending on the manufacturing method, foil is distinguished:

soft (annealed), marked "M";
hard (unannealed) - the letter "T" is assigned to it.

A quality product is called a canvas that does not have folds, spots, tears and other inclusions on the surface. When viewed through the light of a thin canvas, it should be free of gaps and the smallest holes. Thick foil is allowed to have a small number of holes, which is regulated by the technical parameters of the equipment used.

A thin web is wound on sleeves of different diameters. Thick foil is produced in sheets.

Before starting work on insulation, developers are interested in how much foil for a bath costs. Domestic rolled products will be cheaper than imported material. With a roll length of 25-30 meters, the price will be approximately $ 20-30.

The use of foil for warming baths

To determine which foil to use for a bath is better, you need to take into account what material the structure was built from and the conditions for its operation. If the building is a log building with carefully poured walls, then a foil heat insulator is not required for it.

In the case when the bath is built of natural wood, but large in area and does not warm up well, experts recommend sheathing the ceiling and walls from the inside with thin foil, and then covering it with clapboard. You can use a foil cloth for the surface behind the heating unit, as a result of which the steam room will warm up faster.

Despite the fact that a foam concrete bath building is considered warm, it requires high-quality vapor barrier, so the use of foil will be justified, but it is better to opt for laminated products.

Frame and brick buildings must be insulated. For this, heaters for a bath with foil based on expanded polystyrene and mineral wool are ideal (read: ""). The type of this material is chosen for ceilings, taking into account the thickness of the floor and the absence / presence of thermal insulation in the attic.

In addition, the operating conditions matter. If the bath is used infrequently and the procedures are taken for a short time, there is no need to insulate it with foil. When the steam room is used often and are in it for a long time, high-quality thermal insulation will save fuel, and the room will quickly warm up and cool down for a long time.

Performing a simple planking of a bath

When cladding the walls of bath buildings, the foil sheet is attached to the surface or over a layer of thermal insulation. Such work will take little time and will not require much effort.

The process looks like this:

Before sheathing the bath with foil, a frame made of wooden planks is fixed on the wall.
Insulation is placed between the slats.
The top of the insulating material is covered with an overlap foil, the joints between the strips are glued using aluminum tape.
The foil is sheathed with clapboard and a 15-20 cm air gap is made between it and the surface of the foil. This is a prerequisite for efficient heat transfer.

The air gap will reduce the thermal conductivity of aluminum, and since the hot lining will not come into contact with the foil, due to the insulating qualities of the air, direct heat transfer will become impossible. At the same time, infrared rays falling on the surface of the foil sheet will be reflected towards the steam room.

Types of heaters with foil for a bath

In the process of work, a thin soft sheet of foil is easily crushed and torn, therefore, new technologies for its application have appeared.

Now on sale there are:

foil paper;
the cloth;
insulation.

Foil paper

Its other name is paper-based laminated foil for a bath. It is an elastic and dense material and has excellent vapor barrier characteristics. It is produced in two types: foil plus kraft paper and foil plus paper plus polyethylene.

Foil paper is able to withstand 130 degree heat. Resists compressive loads. It holds its shape and is easy to cut. The standard strip width is 120 centimeters. Self-tapping screws, construction staples and nails are used for its fastening. The material is used for cladding baths from the inside. It is not recommended to use laminated foil for the surface of the walls adjacent to the oven.

Foil fabric (foil fabric)

This soft two-layer material is made from fiberglass and foil. The thickness of the foil fabric is in the range of 0.12 –3 millimeters. The canvases must be fastened end-to-end. Foil fabric is used to insulate bath rooms, it can be used to sheathe the walls near the heating unit.

Its main characteristics:

the ability to withstand temperatures up to 500 degrees;
resistance to mold and other harmful microorganisms;
good moisture resistance.

Foil polystyrene foam

Insulation is made on the basis of expanded polystyrene and covered with the thinnest layer of aluminum foil. The material is produced in sheets 1.2x0.6 meters in thickness 2-10 centimeters. They are used for the purpose of warming the premises of a bath building from the inside. The sheets are equipped with stepped locks that prevent the formation of cold bridges.

Foil polystyrene foam has the following qualities:

does not absorb moisture;
reflects about 98% of thermal energy;
differs in vapor barrier properties;
resistant to chemical attack;
safe for health;
has a long service life.

Foil polyethylene foam

This insulation roll with a thickness of 2 to 10 centimeters has a one-sided or double-sided foil coating. It is used in the arrangement of thermal insulation of the internal premises of the baths.

This material is able to withstand temperatures of no more than 100 degrees. It is not used for cladding surfaces near the furnace.

Foil mineral wool

It is produced in rolls or in the form of mats of various thicknesses. Possesses excellent thermal insulation properties. Ideal for insulating frame sauna buildings. Using rolls or mats with foil makes finishing work easier and more convenient.

The best material for bath insulation

Since the cost of energy is constantly growing, the owners of baths and saunas are forced to look for ways to save costs for operating a steam room. When erecting a new building, it is necessary to use materials that have heat-saving characteristics. Baths built of bricks, foam concrete, cinder block and other building materials, except natural wood, need additional protection from heat loss.

When arranging a steam room, you should be especially careful when deciding which foil is best for a bath, since the material must be environmentally friendly and reflect heat well. All these requirements are met by heaters with aluminum foil coating.

Advantages of foil insulation:

The material is versatile, since it is used for walls, ceiling and bath floor.
Foil-coated heaters have good light reflection.
Products are produced in a wide range.
They are used in humid rooms, while they do not need to be treated with fungicidal compounds.
They have high hygienic properties. The inherent properties of aluminum do not create a breeding ground for the growth of fungi and mold.
They do not deform or melt in the steam room at elevated temperatures.
The material is easy to use. It is easy to mount and fix on different planes: vertical, horizontal and inclined.

Baths insulation tips:

If the bath building does not have a commercial purpose, wall decoration with 3 mm foil in rolls will be sufficient.
For commercial enterprises, the solution to the problem of which foil is better for a bath will be the use of laminated products based on basalt mineral base.

When insulating a bathhouse located inside a capital building, it is necessary to take into account the functioning of the central heating, since it heats the air additionally.