Insulation of a wooden house outside with mineral wool for siding. Materials and technology insulation of the external walls of a wooden house Materials for the insulation of a wooden house from the outside
The beam, due to its affordable cost, durability and strength, has become a popular material in the construction of houses. Natural wood creates a healthy indoor climate and has good vapor permeability. Low thermal conductivity is one of the advantages of timber, but insufficient wall thickness causes high heating costs.
Even with careful joining, gaps remain between the lumber, letting cold and draft into the room. You can change the situation by insulating a log house. The process of thermal insulation of a wooden building is distinguished by the availability of technology, so it is really possible to do it yourself.
Why is it preferable to place a heater outside?
External thermal insulation of a log house has its advantages:
- reduced heating costs;
- protection of hygroscopic wooden walls from moisture;
- the appearance of the facade changes according to the individual preferences of the owners;
- no reduction in interior space.
Criteria for the selection of thermal insulation material
When choosing a heater, you should pay attention to its characteristics: elasticity, resistance to burning and moisture, thermal conductivity, breathability. The thickness of the effective layer depends on the temperature in the region and the parameters of the timber. In a temperate climate, 50 mm of thermal insulation material is enough, and in winter frosts below -20 degrees, this figure doubles. The complexity of installation should also be taken into account, because the work is done by hand.
Ways of insulation, what to choose for walls made of timber
Exterior decoration of a log house is carried out in three ways:
- Ventilated façade.
The hinged structure includes a wooden crate, insulation and external cladding made of clapboard, siding or porcelain stoneware. Do-it-yourself facade installation gives the walls additional heat and sound insulation and brings the dew point out. The design is easy to assemble and lasts up to 50 years.
- Sealed with polyurethane foam.
Polymer spraying creates a monolithic seamless surface and strengthens the walls of the timber. The work is carried out using a high pressure apparatus. He mixes the two components and delivers the composition through the gun to the surface to be insulated. Condensate does not collect under the polymer layer, it does not burn, does not rot, and reduces the noise level. After spraying polyurethane foam, finishing with facade material is required. The main disadvantage of this method of insulation is the high price.
- The use of foam boards.
The low cost of the material makes it the most affordable insulation. It is resistant to fluctuations in temperature and humidity, but has a significant drawback - it supports combustion. Fixing the foam on the walls is carried out with special glue. Before mounting the first row, a starting profile is nailed to limit the sliding of the material.
After analyzing the pros and cons of the ways in which a log house can be insulated from the outside, most owners settle on a ventilated facade.
Practical insulation for a wooden house
The best choice for warming the house will be mineral wool. It is made from slag, rocks or glass, so it does not support combustion. The material is easy to fit with your own hands, retains heat well and is affordable.
How to properly assemble a ventilated facade
The technology for the correct installation of a hinged facade includes several stages:
- fastening the crate;
- laying insulation;
- installation of a diffuse membrane;
- fixing the decorative coating.
Work begins with the application of an antiseptic layer to the beam, which protects against decay and moisture. A frame of wooden planks is stuffed onto the finished surface. The step of the vertical crate is 1.5 cm less than the width of the insulation. This will allow you to tightly lay the material, avoiding cracks and cold bridges.
The bars are attached to the wall with self-tapping screws, their vertical plane is set using a level with a plumb line. Mineral wool mats are inserted between the frame slats, pressed tightly and fixed with umbrella dowels. When a wooden house is located in a region with a low temperature, it will be correct to perform external thermal insulation in two layers.
To protect the insulation from moisture, a special perforated film is laid. It does not allow water to penetrate inside, and the moisture accumulated in the cotton is released to the outside. The membrane is overlapped and fastened with staples, its joints are glued with adhesive tape.
The ventilating layer of the facade is created by stuffing planks over the waterproofing. They provide a space between the insulation and the cladding in which air circulates. The second row of rails becomes the basis for the finishing facade coating. Slots for ventilation remain in the lower and upper parts of the structure. They are protected from precipitation by special visors.
Mineral wool is an excellent insulator, but it loses its qualities when wet, so it should be stored indoors. When working with the material, dust and fibers appear, which cause irritation. It is necessary to lay mineral wool slabs in goggles and gloves.
It does not take much time and money to insulate a log house from the outside. The result of high-quality work will be a comfortable room temperature at lower heating costs.
Internal insulation has a lot of disadvantages, among which costs First of all, isolate the formation of condensate. Therefore, your house, especially a wooden one, should be insulated from the outside - in this case, the internal temperature of the walls will drop very slowly. The location of the cold zone in this case will fall on the inside of the insulation, so it will not touch the wooden walls.
It is better to combine home insulation with vapor barrier material installed from the inside - this will not only prevent the penetration of cold from the outside, but also prevent condensate from accumulating in the structure and destroying it. As a result, the house will be warm, and the humidity level will always be normal.
Note! Between the wooden wall and the insulation, you should always leave a small air gap, otherwise mold will appear there and the structure will collapse sooner or later.
The modern building materials market offers a wide range of insulation, among which everyone can choose the appropriate option both in terms of quality and cost. The most popular of them today is mineral wool, so let's start with it.
The main advantage of this material is fire safety, which, in fact, makes it so popular. Moreover, mineral wool provides good ventilation, prevents the formation of rot and fungus, and also conducts heat well.
Minuses:
- the material easily loses its original shape;
- it is short-lived - after a year of operation, almost half of the properties are lost.
The average cost of a cubic meter of mineral wool is approximately 1,500 rubles. This figure varies in one direction or another depending on the manufacturer and the technical characteristics of the material.
Another option that you can resort to when insulating a house made of wood. Styrofoam consists of many granules filled with air, which provides lightness and good thermal insulation.
Pros:
- excellent soundproofing properties;
- long service life;
- ease of installation;
- resistance to deformation and decay;
- high density;
- resistance to temperature changes.
Minuses:
- environmental insecurity;
- prone to rapid fire.
But the main disadvantage of the material can be considered that it cannot be used for insulating wooden houses due to poor vapor permeability and.
A square meter of foam plastic costs from 50 to 300 rubles, depending on the thickness and the manufacturer of the spruce.
Penoplex is also widely used in the insulation of buildings. It is produced by extrusion, as a result of which a material of a homogeneous consistency is formed. The advantages of the material include:
- environmental friendliness;
- incombustibility;
- security;
- ease of use;
- water-repellent characteristics (due to the fact that there are no micropores in the cells);
- the ability to withstand heavy physical exertion;
- durability, resistance to decay;
- low thermal conductivity.
Minuses:
- upon contact with solvents of organic origin, the material is destroyed;
- there are difficulties in trimming and fitting;
- Vapor resistance can sometimes be more of a minus than a plus.
A cubic meter of foam plastic costs about 4,000 rubles. Warming a wooden house with such material is effective, but very expensive.
Note! If you want to insulate your home and protect it without spending a lot of money on it, then it is recommended to pay attention to mineral wool. It is on the use of this material that the technology below is based.
Isoplat is made from coniferous trees, and no chemical binders are added. Due to this, the plate does not dry out and does not deform over time. In addition, Isoplat is environmentally friendly and as effective as the tree itself.
Pros:
- thermal insulation: 12 mm board = 44 mm solid wood
- sound insulation from -23 dB
- elasticity: the plate fits snugly to the frame, breaking cold bridges at the joints
- vapor permeability: the plates remove excess moisture from the wall, preventing the formation of fungus and mold in the house
- ease of installation: Isoplat is pressed against the wall and nailed, a ventilated facade is installed on top and that's it. No more materials and work will be required.
- paraffin impregnation: protects walls from atmospheric moisture
- 100% eco-friendly
Minuses:
- - a higher price compared to other materials, but it will pay off, since Isoplat is guaranteed to "work" for more than 70 years and no alterations will be needed.
The first stage of work is to prepare the necessary tools and building materials.
What will be required in the work
When warming a house you will need:
- mineral wool;
- scotch;
- wooden slats (250 mm thick);
- nails;
- polyethylene film;
- staples;
- boards, approximately 10x5mm;
- slats, 5x3 cm;
- waterproofing.
And now - directly to work.
First stage. Surface preparation
At the end of the installation, the outer walls of the house will remain closed, so for a start they should be protected from harmful microorganisms and decay. For this purpose, special compounds are applied to the surface, which must be allowed to dry completely. Usually it takes a little time and after a few days you can start installation.
Second phase. vapor barrier
Wooden houses are good because they do not need a layer of air between the vapor barrier and the outer surface of the walls. For this reason, you can immediately attach the plastic film. Wooden slats are nailed to a flat surface (about every meter), to which a layer of vapor barrier is attached with brackets. This distance is necessary to ensure proper ventilation. Holes are made at the bottom and top between the slats to eliminate the possibility of moisture accumulation and increase the intensity of air circulation.
The points of attachment of the film to the rails must be sealed with adhesive tape, which will protect the insulation from moisture penetration.
Third stage. Frame construction
Next, you need to create a framework. The boards should be nailed, being installed "on edge", with a step of 1.5-2 cm less than the width of the insulation board. By the way, mineral wool has sufficient rigidity to be placed in a frame without additional fasteners. In any case, the sheets of material will not slip.
Note! Professionals advise installing two layers of insulation in our climate zone at once. It is characteristic that the joints between the plates of the first and second layers should not coincide.
Fourth stage. Waterproofing
The final stage of work is the installation of waterproofing, designed to protect the insulation from moisture penetration. The membrane is ideal for this - its special structure provides air access, thus creating additional ventilation, and at the same time does not allow moisture to pass to the mineral wool.
The waterproofing must be attached to the frame in the same way as the vapor barrier. At the joints, this creates a 2-centimeter overlap. The joints themselves are glued with adhesive tape to ensure tightness.
Fifth stage. Ventilated facade
If you do all these procedures, then a ventilated facade is created in parallel. It is designed to circulate air between the waterproofing and the outer layer of the surface finish. For this reason, it is necessary to create an additional frame layer. A similar crate is being constructed, but this time the slats are used in a different size - 3x5 cm. A fine-mesh iron mesh is installed at the bottom of the frame, which will prevent the penetration of insects and small rodents.
Sixth stage. Facade decoration
What material will be used in the decoration of the facade depends entirely on the design features, financial capabilities and personal wishes of the owner. For example, to give the house an attractive appearance, you can:
- sheathe with clapboard;
- finish it with facade tiles;
- sheathe with boards;
- build vinyl siding.
Siding is considered the most suitable option, but when installing it, you need to follow some rules.
- First of all, when finishing with siding, you should move from the bottom up.
- Be sure to leave a gap of 1 cm between the panels of the material.
- To fix the siding, you must use nails or self-tapping screws.
Possible mounting options
Before you start warming a wooden house, you need to find out what its load-bearing capacity is. In the construction of simple frame buildings, a strip foundation is mainly used. Therefore, in this case, it will be necessary to install an additional plinth, made in the form of a strip under the lining. It is desirable that the base is directly connected to the foundation.
The insulating layer is attached to the frame, we have already talked about this.
Sometimes, when insulating, a hinged frame is used, for the manufacture of which perforated aluminum profiles were used. Also, external walls can be insulated with light materials, for example, pressed flax or wood chips. Of course, the effectiveness of these materials cannot be compared with mineral wool or foam.
As a conclusion
High-quality heaters are available today to every owner of a wooden house. If all the work is carried out correctly, the result will be not only a cozy atmosphere, but also significant budget savings. Moreover, such a house will look beautiful and presentable - in any case, the owner will have something to be proud of.
Video - Insulation of the walls of a wooden house
Many owners of wooden houses consider it necessary to insulate the walls immediately after its construction. However, I would like to note that quite often a mistake is made in this case - it is far from always worth putting new houses made of solid wood into insulating material, since the tree itself has a low thermal conductivity, and, in addition, it is able to create a favorable microclimate inside the rooms .
It is advisable to insulate a wooden house outside with mineral wool for siding if the building has already stood for many years, and, having gone through numerous cycles of temperature changes, the wood has lost its original qualities. This is due to the fact that numerous deep cracks appear on the logs or beams from which the house is built, under the influence of atmospheric influences.
Insulation measures are also resorted to if the wall thickness is small, and the house is located in a region with cold winters. Thermal insulation also helps to create a lower total thermal conductivity of building envelopes and significantly reduce fuel costs.
To insulate a wooden house from the outside, mineral wool is increasingly being chosen, and for decorative exterior decoration, vinyl siding, which is affordable and has a fairly long service life. In addition, the finishing material is easy to install, and if one of the panels is damaged, it can be easily replaced with a new one.
So that after the insulation of wooden walls in the house the optimal microclimate is preserved, and the building itself is not harmed, it is necessary to know the specifics of the thermal insulation process, as well as the operation of the house.
You may be interested in information about what effect will occur if you perform
What causes high moisture content in wood?
You need to know the answer to this question in order to take warming measures more seriously and, not relying on various advice, but logically, make the right decisions.
Everyone knows that wood not treated with special compounds, being constantly in a wet state, is affected by microflora (flexible, mold), rotting processes begin in it, the material loses its strength. After a couple of years, the log in which the mold has settled completely loses its thermal insulation qualities, and then completely turns into dust. Therefore, when insulating wooden walls, it is very important to choose the right materials and install them in such a way as to protect the structure from waterlogging.
The moisture content of the logs before mounting them in a log house should be 23 ÷ 35%. After standing for about a year under normal conditions, the walls dry out, and the moisture in the wood drops to 10 ÷ 18%, depending on the measurement season. It should be noted that if the tree is kept wet for a long time, the level of which will be 20 ÷ 22%, then the formation of fungus in its structure is inevitable. In addition, such an environment is favorable for the appearance of the wood-boring beetle.
No need to think that the wood begins to dampen only because of high humidity, rain, snow or fog. In fact, in winter, when the temperatures in the street and in the house differ, and the humidity in the room is many times higher than the outside, the wood absorbs it into its structure. Absorbing moisture from the inside, the tree, passing through the joints between the logs and micropores, gives it out. The lower the temperature outside and the higher it is in the house, the more moisture passes through the wood structure. About this process they say that the material "breathes".
Violating such a natural balance is by no means impossible. It is unacceptable to conduct insulation in such a way that the exit from the wood to the atmosphere is closed to water vapor. In addition, the insulation also plays a role in shifting the “dew point” - it will be moved outside the wooden wall and fall on the thickness of the thermal insulation material. This will also significantly reduce the likelihood of waterlogging of wooden walls.
Materials for warming wooden walls
So, in order not to disturb the normal temperature balance and prevent moisture stagnation inside the logs, it is very important to follow the correct insulation technology and select the right materials.
The most important condition is a vapor-permeable membrane
The most important element of the insulation system of a wooden house is a windproof diffuse membrane.
In order not to disturb the natural balance of humidity and insulation, it is necessary to create normal conditions for the operation of the building, avoiding obstacles for the release of water vapor to the outside.
Windproof Diffuse Membrane Prices
windproof diffuse membrane
Many builders, doing work “not for themselves”, do not really think about the durability of the insulated house, and cover the wooden wall with a vapor barrier film, which absolutely not allowed. Specialists involved in the study of the construction physics of wooden housing construction and building materials advise completely abandoning the vapor barrier material when insulating wooden buildings in which it is planned to live all year round. Instead, a windproof diffuse membrane should be used, which is attached to the outside of the insulation. This coating is hydrophobic - the water that gets on it simply rolls off, but never absorbs into the fibers. That is, even if water will seep under the siding layer, it will not succeed in getting into the mineral wool layer, and even more so - to the wooden walls.
At the same time, the unique structure of such a membrane absolutely does not prevent the free exit of water vapor to the outside, from the walls and the insulation layer into the atmosphere. Thus, the walls of the house continue to "breathe", spontaneously leveling the moisture balance.
The insulation itself needs wind protection - and this membrane fully copes with this task, preventing the material fibers from weathering and cold air flows into its thickness.
Schematically - the structure of the insulating "pie" on a wooden wall
The ventilation gap left between the windshield vapor permeable film and finishing material, will allow free circulation of air, which will constantly dry the drops of condensate that have appeared on the surface of the membrane.
Optimum insulation - mineral wool
With external insulation of wooden houses, synthetic thermal insulation materials - polystyrene foam, polyethylene foam, etc. are completely excluded. It is also necessary to immediately get away from any materials with a foil coating. All of the listed heaters have vapor barrier qualities, which, as already mentioned, is completely unacceptable.
You should not choose artificial sprayed materials, such as polyurethane foam, for insulation of a wooden house, as it also completely seals the surface and does not allow the tree to “breathe”. Such insulation will lead to rotting and mold inside the house, which is very dangerous not only for the entire building, but also for the health of residents.
The most acceptable option for such work is mineral wool, but also not any. It can be made from different materials: blast-furnace slag (slag wool), molten cullet and sand (glass wool), and from volcanic gabbro-basalt rocks (stone or basalt wool).
Mineral wool prices
mineral wool
For the insulation of a wooden house, the most suitable option is stone wool, which has low hygroscopicity, excellent thermal insulation qualities, suitable density and sufficiently high compressive strength.
The main technical and operational characteristics of this material:
- Thermal conductivity coefficient – from 0.032 to 0.048 W/m×°K.
- moisture absorption- no more than 2% of the volume (in some species - significantly less )
- The density of basalt mats can vary from 30 to 400 kg/m³, as semi-rigid and rigid slabs are produced, as well as mineral felt mats.
- The compressive strength is from 5 to 80 kPa, depending on the type of material and its density.
- Basalt insulation is a breathable material, and this is one of the main conditions for the insulation of wooden structures.
- The most important quality, especially for use in wooden construction, is the incombustibility of the material.
For external insulation of the house, it is recommended to choose semi-rigid heat insulator mats, the density of which varies from 80 to 150 kg / m³. They are usually 600x1200 or 500x1000 mm and are available in a certain range of thicknesses. Rolled material is easier to mount, but its density and strength are lower, it can sag over time, even if it is properly fixed to the wall.
Glass wool can also be used for external heat-insulating work on the walls of a wooden house, but the effectiveness and durability of such insulation will be significantly lower.
But slag should be immediately, categorically excluded. Do not be deceived by its low price - this one has a higher coefficient of thermal conductivity and absorbs moisture well. Increased moisture absorption during operation leads to an increase in thermal conductivity, that is, the material sharply loses its thermal insulation qualities. In addition, the increased acidity of slag wool is absolutely not useful for natural wood.
Experts recommend using environmentally friendly hemp or linen mats for internal and external insulation, which have low thermal conductivity, good vapor permeability and sufficiently high resistance to moisture. But the biggest disadvantage of these materials is their high cost.
You may be interested in information on which one to choose for a bar
The required thickness of the insulation of a wooden house
The thickness of the insulation is selected depending on the thickness of the walls and the average winter temperatures of the region where the house is built. Most often, the heat insulator is mounted in two layers, the first of which is 100, and the second - 50 mm. If necessary, the thickness can be increased, but for this you will have to fix another row of crates.
However, it would be nice to accurately calculate the thickness of the insulation layer - in order to prevent low insulation efficiency or, conversely, not to spend extra money for excessive, unnecessary thermal insulation in specific conditions. Performing the calculation is not so difficult.
The principle boils down to the fact that the total thermal resistance of a multilayer wall structure should not be lower than R(m²×° With/W) calculated by experts for the given region.
To simplify perception, the values of this indicator are indicated on the proposed map-scheme of Russia. You should choose the upper value, for walls (indicated by purple numbers).
Since the wall structure is multi-layered, its total thermal resistance will be equal to the sum of the resistance of each of the layers, which affects the insulation qualities of the house.
R=R1 + R2 + R3 …
Well, the thermal resistance of each layer is expressed by the formula:
Rn = hn / λn
hn is the layer thickness.
λn is the coefficient of thermal conductivity of the material.
When insulating a wooden building, such layers can be:
1 - the wooden frame itself. Please note that the thickness of the frame, folded from round timber, is taken somewhat less than when using a rectangular beam. This should be taken into account when performing measurements.
2 - interior decoration, if, of course, there is one. In wooden houses, the walls can remain unfinished inside, sheathed with natural clapboard, MDF clapboard, plywood, OSB, sometimes drywall is used for painting and wallpapering.
3 - The layer of external insulation - the value that you want to find.
There may be more complex "pies", and each layer has its own calculation. But usually they try not to “spoil” natural wooden walls from the inside with synthetic materials in order to preserve the natural virtues of wood.
The diagram also shows:
4 — vapor-permeable hydrophobic windproof membrane.
5 - frame details ( battens).
6 - siding. Facing with siding is separated from the insulation by an air ventilated gap (7). Thus, no matter what material the panels are made of, they do not participate in the overall thermal insulation of the wall and are not taken into account.
Thus, in order to calculate the required insulation layer, you need to know the thickness of each layer and its thermal conductivity coefficient.
As a result, the calculation formula will look like this:
Well = (R– H1/ λ1 – H2/ λ2 – H3/ λ3… ) × λу
The value of the thermal conductivity coefficients of materials is easy to find in reference books, and this parameter for the selected type of mineral wool ( λу) must be indicated on the packaging or in the accompanying documentation.
For ease of calculation, we recommend using the built-in calculator, specially programmed for natural wooden walls. It provides the ability to specify, in addition to the wall itself, two more layers of decoration made from natural materials.
To favorites!
The question "How to properly insulate?" - the undisputed weekly leader of the section "". Timbered and built several decades ago, they are already aging and begin to let the cold through in the winter months.
Mistakes when warming a wooden house
So it is very important to avoid possible mistakes, which regularly occur with unskilled wooden insulation with modern materials. Let's look at the most common of them.
Mistake #1. Log house insulation without wood inspection
As a rule, already “old” log cabins are insulated. On the one hand, it is technologically convenient: the log house has finally settled down and the dimensions of the structure remain unchanged. However, the past years could not but leave traces on biologically living material -.
Therefore, before the planned insulation, which implies that there will be no access to the logs for many years, it is necessary carefully examine all crowns and reject defective fragments. If a devouring wood is wound up in the logs, I will make a cautious assumption that it is already impractical to insulate the house. A cardinal cure for such a case, except for a week of forty-degree frost, has not yet been invented. Read more about this problem in the articles: Good wood should be impregnate with a fire-fighting and antiseptic composition and dry thoroughly. Performing insulation on raw wood is a mistake.
Mistake #2. Inattentive attitude to the caulk
Traditional caulking is performed, strictly speaking, not to insulate the log house, but to prevent it from blowing, which ultimately affects the preservation of heat in the house.
Deciding to insulate log facades, pay attention to the condition of the caulk on all crowns. Do not dismiss this operation. Perhaps it is due to 2-3 defects in this natural insulator that it is cold in your house in winter.
At the beginning of 2016, a reader turned to the editorial office with a request to help with modern insulation. Word for word, it turned out that cunning birds had long been pulling caulk fibers from her log house into their nests.
It seems that after this fact was clarified, our esteemed reader's craving for total warming weakened somewhat.
Without plunging into the basics of building heat engineering and without delving into the meaning of the obscure phrase "" (which underlies the choice of location), take the craft postulate on faith: insulation of buildings is carried out from the outside. Such an installation improves the operation of both the wall bearing material (wood crowns) and the insulation itself. Otherwise, both the insulation and the wood of the logs will get wet from wet vapors, which are inevitably found in the atmosphere of human habitation. Of course, we are not striving for this at all. You can read more about the features of warming the outer walls of a wooden house in the article of the same name.
Mistake #4. Rough choice of thermal insulation material
Construction markets in the literal and figurative sense are inundated with a variety of heat insulators.
However, if we introduce a strict systematization into this abundance, it turns out that everything dominates 3 types of materials suitable for log cabins. These are heaters:
- from ,
- from glass wool
- - cellular and extruded.
I am not opposed to the use of this material, but I vote with both hands for the thoughtful use of it. There, for example, where the fire will never reach - in the foundation, in the basement, in the blind area. He truly has no value here.
Choosing between glass wool and a mineral counterpart is more difficult. Both are perfect for warming a log house. You will learn about which thermal insulation materials are preferable from the point of view of safety from the article.
Mistake #5. Careless attitude to the transportation and storage of material
Thermal insulation materials must be dry. Only in this case they "keep" heat. And if the material gets wet, then its thermal insulation ability decreases landslide.
Remember the common "kitchen" situation: with which potholder will you grab the metal handle of a hot frying pan - dry cloth or wet / wet? I am sure that after a moment's thought, you will choose the dry option. So the insulation must always be dry. At factories during production, it is packaged in a packaging (often in shrink) film and is quite well protected from climatic moisture. But it’s worth removing the film ... Therefore:
- Unpack the insulation a day before use and definitely under a canopy, and even better - in a warm house.
- After fixing the insulation on the wall go directly to its lining plastering method or safety panels (etc.).
- Do not leave heaters open for a long time, risking getting them wet "to the skin" with summer slanting rains.
Mistake #6. Choice of flexible mats instead of rigid slabs
In the construction market, you can find 2 options for thermal insulation materials - flexible mats and rigid plates. At first glance, these are exactly the same materials. So what to choose for facade insulation?
If you decide to opt for mats, you will be mistaken, because over the years, the insulation in a vertical position begins to sag in some places, forming cracks into which cold air rushes - the same ones that disavow all the consumer charm of modern heaters.
Rigid plates keep the sizes invariable during all term of operation. It is quite possible to walk on the slabs laid on the roof structure without losing the quality of thermal insulation.
Why, then, are flexible mats produced? - They are irreplaceable when insulating horizontal surfaces- underground space and floors. There, in principle, they cannot sag and form gaps for heat consumption.
Mistake #7. Incorrect determination of the thickness of the thermal insulation layer
To the question: “How thick should the heat-insulating layer be?” you will find a reasoned answer in a recently published article.
Here we can only confirm that when insulating a log house, two layers of material 50 mm thick will suffice placed one on top of the other. I will make a reservation that two layers are enough for the climatic conditions of central Russia. In the North, three layers of insulation will have to be placed on a wooden wall, and in the southern regions it will be possible to limit one to one.
In conclusion, I would like to give a photograph of a truly unique structure.
What is its originality? The house was built at the end of the 19th century. The house is log, but the logs, united by horizontal dowels, are installed vertically. It was insulated in the spring of 2016 with mineral wool insulation (100 mm) and lined with chipboard panels. And the entrance group is made of monolithic reinforced concrete. Truly, technologies from three different centuries have merged on a tiny spot of development.
Wooden houses are considered one of the most popular types of buildings, especially if we are talking about the countryside and the buildings of the beginning and middle of this century, where many still have rubble. Not everyone can change housing, and it is not always possible to do this. But nevertheless, the issues of energy saving and energy efficiency in our time of high tariffs for resources and utilities are of concern to everyone. And today we will talk about how to insulate wooden houses from the outside.
Features of thermal insulation of wood
Any wood has a property that allows it to absorb moisture. With the help of various impregnations, it is possible to reduce the hygroscopicity of such a material, but it is not possible to completely eliminate this property. If there is an effective ventilation system, then the moisture can evaporate quite quickly and effectively and it will not have time to have any negative impact on the wood, which will allow maintaining a good microclimate in a village or city house.
But the violation of the movement of air masses leads to the fact that condensate begins to accumulate and the tree begins to swell, due to which fungus and rot begin to appear on it, and the air begins to smell characteristically. In order to avoid such problems, it is recommended to follow these tips:
- use only insulation with good vapor-permeable characteristics;
- it is better to insulate dry walls, but not wet and damp;
- cover the thermal insulation with a waterproofing membrane on both sides;
- leave a small air gap between the finish and the insulation.
If the walls of a wooden house are planned to be painted, or if it is simply necessary to insulate the seams, then the paint with sealant must also be chosen to be vapor-permeable.
As a rule, these are those that are made on an acrylic basis. And of course, the surface must be prepared as much as possible before warming. In addition, the logs themselves or the surface of the outer boards must not be damaged by pests such as bark beetles.
Facade insulation methods
It should be said that for the insulation of a wooden house from the outside, there are two technologies for external insulation:
- ventilated facade;
- wet facade.
The first technology is suitable for frame houses. The frame is mounted on the walls, after which it is sheathed with siding, clapboard or some other finishing material. In this case, the insulation is placed between the finishing material and the wall. This technology is very good in that it excludes wet work, and the facade itself in this case will be more durable and durable.
In the second case, the walls of the house are simply pasted over with insulation, after which they are plastered using a technology specially developed for this.
Now let's talk in more detail about the features of each of the methods.
Ventilated facade technology
The process of creating a so-called ventilated (or hinged) facade includes several parts:
- facade preparation;
- arrangement of the ventilation gap and installation of the frame;
- frame sheathing.
If we talk about a heater that can be used with this method, then it should be said that mineral wool would be the best solution. Many people want to carry out foam insulation.
And, in principle, with this method, its use is also allowed. It is only necessary to remember that the foam plastic resists the effects of fire very poorly, and also does not allow steam and moisture to pass through. And this can negatively affect the microclimate inside the house. Therefore, in this case, it is better to give preference to mineral wool.
If we talk about racks for the frame, then either bars or boards are used for it. They can be attached to the walls using brackets or metal corners. By the way, as an option, you can apply a profile that is used to install drywall. In addition, you will need a vapor barrier film that will protect the insulation from getting wet, the material that will be used for finishing: siding, lining, block house, or some kind of facade material.
Also, to implement this method, you will need an interventional heater. Usually, jute tow is used in this capacity, which acts as an excellent protection for the seams, but you can use special foam or any other materials that work. You will also need a wood preservative so that it can resist moisture. It is usually applied under plaster.
Now let's talk about the features of another method.
Wet facade technology
It consists of the following parts:
- facade preparation;
- installation of insulation;
- reinforcement;
- painting.
Speaking a little more, in this case it is also better to give preference to such material as mineral wool. In addition to insulation, in this case it will also be necessary to purchase a special glue for mineral wool, dowels in the form of umbrellas, a special reinforcing mesh made of fiberglass, perforated corners, a primer, paint for the facade, as well as decorative plaster. After all these materials are purchased, you can begin to work.
Material characteristics
The decision to insulate a wooden house must be made with an eye to the quality of its construction. If the thickness of the walls is chosen correctly, then it may not be necessary to additionally make thermal insulation. But it is necessary to insulate a wooden house if it is cold in it. And if he is also old, then, most likely, he simply cannot do without it.
But at the same time, it is important to choose materials for this so that their effectiveness is maximized. Not all heaters are recommended for insulating houses of this type from the outside.
The first category does not violate the microclimate of the house, as it allows it to breathe. The second category of materials will be more affordable in terms of price, but the use of such materials may not always be safe for health. But the question, which is the best way to insulate a wooden house, is really very important. Those who prefer natural materials most often use algae mats, adobe or hemp fiber. Sometimes homeowners also resort to wood and sawdust insulation. But this is, say, not a very ecological way of warming.
And those who believe that artificial thermal insulation is not the worst solution can insulate houses with extruded polystyrene foam, basalt slabs, isopine, isover, foam plastic and even expanded clay.
You should also give the following list of artificial heaters for the house:
- mineral insulation, which includes various types of wool: stone, glass wool and basalt;
- penoizol;
- ecowool;
- Styrofoam;
- polyurethane foam.
In general, as you can see, the choice of heaters for creating thermal insulation of a wooden house is very large. But how do you choose the best solution? You can try to study the technical characteristics of heaters, which will be discussed below.
stone wool
This material is classified as non-combustible, since it easily withstands heating up to 600 degrees and does not change its physical properties and characteristics under the influence of such a temperature. Also, stone wool has good vapor permeability and low thermal conductivity. Most often, this material is presented in the form of plates or mats, and is covered with kraft paper, fiberglass or foil. Basalt slabs are quite dense, which allows them, with properly performed thermal insulation, not only not to shrink, but also to retain their shape well throughout the entire period of use.
In addition, this material perfectly resists the appearance of microorganisms. Mounting such a plate is very simple due to its low weight and size.
If we talk about the shortcomings, then there are not so many of them in such a plate. The main thing can be called the low strength of the fibers: if the material is squeezed or cut, then dust is quickly formed, which is very easy to inhale. For this reason, it is better to work with the material after putting on a respirator. Another disadvantage of this material will be a rather high price, so if the budget is small, it is better to look for alternatives.
Ecowool
The production of ecowool is carried out from the waste of the cardboard and paper industry. For this reason, this type of insulation is 80 percent cellulose. In order to improve the characteristics of cellulose, its fibers are mixed with flame retardants and antiseptics. Such a material can absorb and release water without losing its thermal insulation properties. If you make a choice in favor of such a heater, then condensate will never appear. In addition, it has excellent soundproofing properties, and it does not emit any harmful substances. By the way, insects or rodents do not start in such a heater due to the presence of special additives in its composition.
This type of insulation is a loose, light gray mass, which is tightly packed in bags from 15 kilograms. Before warming, the mass is poured out of the bag, loosened with a mixer, and then laid. The effectiveness of such a material depends on the density of the layer. If the material is compacted too weakly, it shrinks very quickly and forms cold bridges. But if such cotton wool is laid tightly, then it will not change its characteristics during the entire service life.
If we talk about the shortcomings of ecowool, then first of all we should name the technology of its laying. This requires a special pneumatic installation, which is expensive and requires special knowledge. That is, in this case, it is also necessary to spend money on the search for certain specialists.
glass wool
Glass wool is made from broken glass melts, where borax, limestone and other components are added. The link in this case will be either bitumen or synthetic type polymers. Glass wool has long fibers, which allows it to surpass analogs on another basis in terms of elasticity, and also to have a high mechanical density, despite its low density.
It should be noted that glass wool is vapor-permeable, perfectly retains heat and is not afraid of exposure to substances that are chemically aggressive. It does not burn and calmly withstands heating up to 450 degrees without changing the physical properties. And also it perfectly resists sudden changes in temperature.
Glass wool is produced in the form of mats, plates and rolls, including those with a foil coating. Its greatest disadvantage can be called the causticity of the fibers, which cause severe irritation of the human skin and easily get into the eyes and lungs. In addition, it is quite fragile, which is why it is quite difficult to work with it - before laying it, you must wear good and thick clothes, as well as gloves.
Styrofoam
This material is the most affordable in terms of cost. It has excellent performance characteristics, which allows using it to significantly save on heating. This material is made in the form of panels of various sizes and thicknesses. For carrying out insulation work of an external nature, a material with an average density is used. It is important to understand here that the greater the density of the insulation, the worse its thermal insulation qualities will be. True, the resistance to stress will be higher. Too dense material is usually used for floor insulation.
This material has a small mass and is a good barrier not only to cold air masses, but also to sound. It has a low thermal conductivity, due to which it retains the accumulated heat in the room for a long time. It is easy to cut and attach to the wall.
In addition, it is resistant to temperature extremes and exposure to ultraviolet radiation, does not absorb moisture and has a considerable service life. At the same time, this material also has a number of disadvantages. Its mechanical strength is extremely low: the material is very easy to break and crumble. For this reason, after fixing to the wall, it will require protection with reinforcement, as well as applying a decorative coating. By the way, they can also do interior decoration by placing it, for example, under drywall.
The disadvantage of the material can also be called its poor resistance to fire. Moreover, when exposed to high temperatures, it can release substances hazardous to health. By the way, if it is supposed to use glue to fix the material, then you need to find out if this or that particular brand of glue is suitable, since some types can destroy the material.
slag wool
To create this type of mineral wool, blast-furnace slags, that is, waste from the metallurgical industry, are used. This determines the availability of this type of material. Slag wool is slightly more thermally conductive than basalt insulation. The material can be heated up to 300 degrees Celsius without problems. If the temperature is higher, then it begins to deform and lose its characteristics. As a rule, slag wool is produced in rolls and plates, often coated with foil. It has low rigidity, which is why it is excellent for thermal insulation of uneven surfaces, as well as excellent thermal and sound insulation characteristics. It also cannot grow mold.
But slag wool also has a number of disadvantages:
- hygroscopic;
- does not like temperature changes;
- releases acids when exposed to moisture;
- Causes extreme irritation upon contact with the skin.
polyurethane foam
Polyurethane foam is considered the material of a new generation. It is a sprayed heat insulator. It absorbs moisture minimally and also has minimal thermal conductivity. The most interesting thing is that the higher the density of polyurethane foam, the higher its thermal conductivity. In fact, this material, as it were, envelops the building and does not let in either cold air masses or moisture.
This material is an excellent solution for buildings in areas with an arctic climate, as its characteristics are extremely effective for such natural conditions.
True, experts are rather ambiguous in assessing the need to use this material as a heater. According to some, it is not worth using polyurethane foam for wooden buildings, since the tree simply does not breathe, which is why its slow destruction begins. According to others, if you correctly calculate the thickness of the polyurethane foam coating for wooden walls, then the surface will always be dry and perfectly protected from decay, and the moisture exchange that wood needs will be carried out inside the room, and not outside.
Natural heat insulators
As mentioned above, in addition to artificial ones, there are also so-called natural heat insulators. These include boards made from sawdust of the type Steico Flex, straw. And you can also use clay insulation, which is also considered a heater. In general, this category of heaters from the point of view of environmental friendliness is an excellent solution. In addition, they are inexpensive. But their main disadvantage is the complexity of creation. Also, flax fiber is used as a natural insulation, which has excellent antiseptic properties and prevents the appearance of mold and fungus. This material is easy to cut, install, and easy to work with.
Separately, it is necessary to talk about the Steico Flex material. This material is a wood fiber mat that is easy to install and process even without the use of tools.
Such material can not only insulate the walls, but also the floor, as well as the ceiling. In addition, such a heater will be an excellent solution not only for a wooden house, but also for a house made of chopped timber or lined with bricks. It also has excellent noise isolation characteristics and responds well to temperature changes.
Its use allows you to make the microclimate in the house as comfortable as possible for its inhabitants.
Thickness calculation
An important point is the calculation of the thickness of the insulation. It should be noted that the thickness of the thermal insulation layer depends on the thickness of the walls of the house, as well as climatic features. But to know how thick the insulation should be is simply necessary. If there is too much of it, then this can adversely affect the house, and an insufficient amount will cause the low efficiency of the insulation process as a whole.
In addition, this parameter also significantly affects the design of the frame, since it is very important to know at what distance from the walls the guides for the outer skin should be placed. It is not difficult to make such calculations yourself, especially if you apply a certain calculation methodology. Its essence is that the total heat transfer resistance of a wall of several layers of construction R should not be less than calculated for a certain climatic region.
It should be noted that the wall is not only the log house itself, but also the entire interior finish, thermal insulation layer, as well as the exterior finish of the facade. Each layer has its own thermal resistance index, which also needs to be calculated.
To determine the specific required thickness of the insulation, it is necessary to know the thermal conductivity of each layer, as well as their thickness. The calculation will be carried out according to the formula: Rn = Hn / λn, where:
- Hn is the thickness of a specific layer;
- λn is the coefficient of thermal conductivity of the material from which this or that layer is made.
As a result, the calculation formula will look like this: Hu = (R– H1/ λ1 – H2/ λ2 – H3/ λ3…) × λу, where
- λу is the thermal conductivity coefficient of the specified thermal insulator;
- H is the thickness of the insulation.
It is quite easy to find such coefficients. Sometimes manufacturers even indicate them on the packaging. Measuring the thickness of the layers is also not difficult. If there is no desire to calculate everything manually, then you can use an online calculator. It already has all the necessary basic and frequently used building, insulation and finishing materials.
Preparatory work
If we talk about the preparatory work before warming the house, then they should be carried out in the dry and warm season so that the walls are not frozen or damp. The surface of the walls must be cleaned as efficiently as possible from dirt, dust, moss, fungi. Be sure to carefully inspect the intervents seams. If you find any voids, then they must be re-sealed with a sealant, and then closed with a sealant. The same method can be used if you find deep cracks in the wood of a log house.
After that, priming is carried out. The primer is applied with a brush, carefully processing all the recesses, irregularities, as well as the end sections of the logs.
Note that if the tree absorbs the primer too quickly, then it is applied in two layers. After that, it is necessary to wait for the surface to dry completely and only then proceed to the process of warming itself.
If the work is carried out using the technology of a hinged facade, it is required to carry out its preparation, which consists of the following stages:
- the implementation of the dismantling of all elements of the hinged type that may interfere with the work (antennas, visors, window sills and ebbs);
- treatment of walls with antiseptic impregnation;
- closure of interventional gaps with a heater, if any.
In general, this is an approximate list of preparatory work. But it may differ depending on the type and structure of the house, the chosen insulation technology, as well as the features of the building itself.
Installation steps
Let's consider an exemplary warming algorithm both in the case of ventilated facade technology and in the case of wet facade technology, which are done by hand.
So, if the preparatory work on the creation of a hinged facade is done correctly and the technology is followed, then after that the installation of the frame for insulation begins.
At the first stage, it is necessary to equip the ventilation gap. To do this, attach boards with a thickness of 2 centimeters to the walls. You can arrange them however you like. The main thing is that later you can attach racks to them.
After that, we attach a vapor barrier film to the boards using a stapler. Be sure it must be stretched and overlapped so that there is space between it and the wall. Places where there will be joints should be glued with tape. It should be noted that the insulation of the ventilation gap is important, because if this is not done, moisture may begin to accumulate between the insulation and the wall, which will lead to bad consequences. After that, the racks are installed. First, two extreme racks are mounted, between which the ropes should be pulled. These will be a kind of beacons for intermediate type rails. The installation of the outer racks is carried out at the same distance from the wall and only vertically.
If the boards are used as drains, then they should be strengthened with metal corners and self-tapping screws. After that, the installation of intermediate rails is carried out, which are located at a distance of 1-2 centimeters from the mineral wool slabs.
Now it is necessary to lay heat-insulating material in the space between the racks. As a rule, in this case it is better to use mineral wool. The mats should fit as close as possible to each other and the racks so that there are no gaps in the insulation. After that, a vapor barrier film is attached to the frame. It should also be overlapped. It is fixed with the help of horizontal rails, which will also hold the insulation. This completes the insulation of the facade in this way.
After that, the frame should be sheathed, which will be the final step. Finishing may vary. If you do not have any pronounced preferences, then focus primarily on the price and quality of the material.
For example, lining is an eco-friendly material that allows you to maintain an attractive appearance of the house. And if you take vinyl siding, then such material is easy to clean and does not require any special care.
If you decide to still apply siding, then the sequence of actions will be as follows:
- it is necessary to carry out the installation of the starting profile, which should be placed horizontally around the perimeter of the house (it will not be superfluous to leave a distance from the ground or blind area to the profile of about ten centimeters);
- appropriate profiles are mounted in the corners of the house;
- the first row of panels is installed: from below, the siding is inserted into the starting profile, and from above it and the crate are connected using self-tapping screws;
- according to this mechanism, the whole house is sheathed with siding;
- before installing the last panel, it is necessary to fix the final profile;
- at the end, the installation of the remaining elements is carried out: ebbs, slopes, and so on.
This is where the siding ends. It should be said that according to the same scheme, the house is sheathed with clapboard, thermal panels or other materials.
If we are talking about a wet facade, then after preparation, the walls of the house are immediately pasted over with mineral wool for plastering. To begin with, we prepare the glue, after which we apply it to the mineral mats with a notched trowel. It will not be superfluous to use the building level, as well as pull the beacons so that all the plates are located in the same plane. After all the walls of the house are pasted over, the mineral wool should be fixed to the wall with the help of umbrella dowels.
Now window openings, including gables, are pasted over with mineral wool. Dowels do not need to be installed on window slopes, but it is necessary on door slopes. After that, we apply the rule to various sections of the walls and check if there are any bumps. After that, glue the perforated corners on the outer corners with glue. In the final, we cover the dowel caps with glue so that the facade is smooth.
Now we carry out the process of reinforcement, which is also called rough plastering. First, we prepare the mesh by cutting it into pieces of the required size. Then we cut pieces for slopes. Now we glue the grid on the slopes, after which we do the same actions with the walls. When everything is dry, apply the glue again with a thin layer and eliminate irregularities. Now it remains only to apply decorative plaster. This process will be easier than reinforcement, and is carried out in the following sequence:
- the walls of the house are treated with a primer (it is best to apply it in two layers);
- the solution is prepared according to the instructions on the pack;
- decorative plaster is applied to the walls with a spatula, while the layer should be as thin as possible;
- when the plaster begins to set on the walls, it is necessary to wipe it with a small one, which will allow you to create a pattern;
- it remains only to paint the house, and everything will be ready.
In general, as you can see, it is possible to insulate a wooden house from the outside on your own. But it is important to observe the technology of this process as much as possible, to have a clear understanding of the nuances of the work and to determine exactly which method of insulation and what material is suitable for this.