Insulation of the floor allows you to make living in a country house much more comfortable. In addition, by performing this procedure, the owners of a private low-rise building are able to save on heating in the winter. Different materials can be used to warm floors in country houses. But more often than not, a similar procedure is carried out using mineral wool, expanded polystyrene or expanded clay. To lay such materials is allowed, of course, including between the lags.
Log floor construction
On the lags, the lower floors of country houses are collected in most cases. And if during the construction of brick or block buildings the floors can still be poured, for example, with concrete, then in wooden they are almost always made using boards and timber. They usually collect floors on logs using this technology:
the earth is carefully compacted and leveled;
install retaining short columns of brick or concrete;
spread the posts with a waterproofing pad;
stack logs;
perform sheathing of the beams with a board.
This is the design of the floors on the logs in private homes. If necessary, their insulation is carried out with the preliminary dismantling of the boardwalk and the installation of insulation boards or backfilling of expanded clay between the beams.
The use of mineral wool: advantages and disadvantages
It is with this material that floor insulation on logs in wooden or stone houses is most often produced. Private builders attribute the advantages of mineral wool primarily to its low cost and ease of installation. For wooden houses, this material is simply ideal also because it is fireproof.
Laying between the lags of mineral wool slabs is not difficult even for an inexperienced builder. But when installing such material, of course, certain technologies must be followed. Some disadvantage of basalt wool is that it is afraid of water. If such plates are saturated with moisture, they will lose their warming characteristics.
Therefore, when laying mineral wool, it is mandatory to use hydro- and vapor barrier materials. At the same time, only high-quality films are worth buying for such plates. Such materials must be laid with the exact observance of the required technologies.
How to choose mineral wool
In principle, there is no special need to buy too dense material when insulating the floor on logs in a wooden house or a stone one. Indeed, the main load in such an overlap during its operation in the future will fall on the actual beams themselves. In addition, a very dense mineral wool usually retains heat worse.
However, too soft basalt slabs for floor insulation in this case should not be used. According to the regulations, for laying between logs it is supposed to use mineral wool with a density of about 30-40 kg / m 3 . Such plates are relatively inexpensive.
In most cases, basalt material of the P-125 brand is used to warm the floors along the beams. You can also buy cheaper P-75 boards for this purpose.
In terms of thickness, mineral wool for floor insulation is selected depending on the climatic features of this particular area. For cold regions, they usually buy material no less than 150-200 mm. In warmer areas of the country, you can use cotton and thinner and cheaper.
In cold regions, experienced builders advise using two layers of mineral wool to warm the floor between the logs in a wooden house or stone. In this case, 100 mm material is usually purchased. At the same time, they stack it in such a way that the plates of the upper layer overlap the seams between the sheets of the lower one.
The width of the mineral wool is chosen depending on the step between the lags. Mount this material in the space between the beams relied on by surprise. Most often, mineral wool slabs are 80 cm wide. When constructing a house, in most cases, beams are located at this distance.
Mineral wool floor insulation: installation technology
Since in the construction of country houses, beams are in most cases laid on posts, the distance from the ground to the floor surface is usually significant. To fill all this space with a heater, of course, is not worth it. In this case, the insulation of the floor will turn into a procedure that is unreasonably expensive.
For mineral wool in this case, in the floor structure, you just need to equip the support. To do this, on the logs along the lower edge of their vertical planes along the entire length, they fill bars with a width of 4-5 cm. Next, they are laid and secured with nails or self-tapping shields, for example, from a waste board or plywood. In the future, mineral wool slabs are laid on the resulting base.
To prevent such an insulator from damping, when insulating the floor between the lags, before installing it, boards made of boards or plywood are carefully forged with a waterproofing insulator. You can use for this, for example, a thick plastic film or roofing material. It is best to lay such material in two layers.
At the next stage, between the lags, the plates of the actual mineral wool are mounted on the waterproofing pad. There is no need to attach this material to the base in any way.
After the mineral wool is laid, proceed with the installation of the vapor barrier. This material is spread on top of the lag and cotton wool with an overlap of 10-15 cm. The joints are fixed using masking tape.
At the final stage of floor insulation, the coating itself is mounted from the boards or, for example, OSB boards. Further it remains only to lay some finishing material.
Some nuances
When insulating on lags in a wooden house or stone mineral wool, among other things, the following recommendations should be observed:
lags before warming must be cleaned of traces of rot and thoroughly treated with antiseptic, antifungal and preferably water-repellent;
in cold regions, the top sheets of mineral wool are laid so that they overlap the seams of the lower layer by at least 10 cm.
The technology described above is used to warm the floor in already built houses. When performing insulation of the lower floor directly during the construction of the building, it is better to use a slightly different technique. Mineral wool itself and a vapor barrier in this case are mounted in the same way. The waterproofing is laid in the floor even before laying the logs. At the same time, such material is mounted with an overlap on the walls of at least 15 cm.
When using this technology, the lags, if the floor is not subjected to too serious loads in the future, are not attached to the posts. In this case, the waterproofing insulator will be better to protect.
Pros and cons of using polystyrene foam and polystyrene
With the use of such material, ceilings in country houses are usually insulated with a screed. However, sometimes foam sheets are also used to warm the floor along the logs. In this case, not only dense and durable polystyrene foam can be used, but even a softer and more fragile foam.
It is advisable to use such material instead of mineral wool when the house is built, for example, on a very damp site. Unlike basalt slabs, foamed moisture is not at all afraid. The advantages of such insulation also include ease of installation. Foam polystyrene is almost as easy to lay as mineral wool.
In terms of environmental safety, such materials are basalt, according to many builders, are also superior. However, stoves of this type will not harm people living in the house only if they are used at not very high temperatures. When heated, this material, unfortunately, begins to release toxic styrene.
The price of foamed slabs is higher than mineral wool. Warming of a wooden floor on logs with polystyrene foam or polystyrene foam will most likely cost more. This, of course, can be attributed to the disadvantages of such material.
Also a minus of such plates is the fact that they can make moves and arrange nests of mice and rats. This is especially true for soft foam. Therefore, in those houses where there are rodents, it is better not to use this type of insulator.
Insulation of the floor on wooden logs in a bath or sauna is most often also done with the use of expanded polystyrene. Mineral wool in such buildings is never used. Universality of application, thus, of course, can also be attributed to the advantages of foamed plates.
Insulation of the floor on logs with polystyrene foam: material choice
Polyfoam floors in country houses today are extremely rare. This material, unfortunately, is very short-lived. Most often, private developers still use expanded polystyrene for floor insulation, including lags. Such material has the best operational and technical characteristics and lasts a long time.
As in the case of mineral wool, too thick foam sheets for laying between the logs are optional. Mounted between the beams is usually such a material no more than 15 kg / m 3 .
To insulate the floor in houses built in cold regions, they usually choose polystyrene foam 10 cm thick and lay it in two layers. For buildings erected in warm areas, it is allowed to use 15 cm material with laying in one layer.
Mounting technology
The method of installing foamed plates between the logs when insulating the floor is not much different from the methods of laying mineral wool. Although polystyrene foam is not afraid of moisture, it is still recommended to use hydro and vapor insulators in its application. With prolonged damping, the destruction of such a material will in any case go faster.
Expanded polystyrene is mounted on lags usually by the following technology:
supporting beams are packed on the beams along the lower edge;
mounted plank rough base;
waterproofing is being carried out;
polystyrene foam sheets themselves are mounted;
vapor barrier film is stretched;
final floor boards are mounted;
fine finishing or facing material is laid.
Using this technology of floor insulation with foam between the lags allows you to make living in the house much more comfortable. Insulating rooms from the cold, such material is usually slightly better than mineral wool.
Installation Nuances
Unlike mineral wool, polystyrene foam and polystyrene are inelastic materials. Therefore, after laying such plates, gaps usually remain between them and the beams. In order to insulate the floor on logs with polystyrene foam or polystyrene foam as efficient and high-quality as possible, such gaps, of course, must be closed.
Before installing the vapor barrier, the gaps between the expanded polystyrene plates and the logs must be blown out, for example, with mounting foam. As soon as this material hardens, the parts that come out are cut off with a sharp construction knife.
Expanded clay application: pros and cons
Most often, as we found out, in our time, mineral wool is still used to warm the floor along the logs. Earlier, for this purpose, expanded clay was used in most cases. Such material is used to isolate floors from the cold sometimes even today. The unconditional advantages of expanded clay include:
This material is made from environmentally friendly materials. In this regard, expanded clay is superior to both expanded polystyrene and mineral wool. The advantages of this material include durability. Such a heater will serve in the floor exactly as long as the house itself will be operated.
Some of the disadvantages of expanded clay is the ability to absorb moisture. Also, the disadvantages of this material include the fact that in our time it is often difficult to find on sale.
How to choose expanded clay
This material is usually rounded with a porous structure of fractions from 5 to 40 mm used for floor insulation on logs. Such expanded clay belongs to the group of gravel. Sometimes, expanded clay sand is also used to warm the floor with beams . The particle size of such bulk material in most cases does not exceed 5 mm. Very often, a mixture of gravel and sand of this variety is also used to warm the floor.
Expanded clay crushed stone, whose elements have uneven edges, are practically not used for backfilling between logs. This type of material is intended mainly for use as a filler in the manufacture of concrete mixtures. But if you wish, to the expanded clay mixture of gravel and sand, of course, you can add a little crushed stone of this variety.
Warming a wooden floor with expanded clay between the lags is a great way to increase the comfort of living in the house. But such material, as already mentioned, can absorb moisture. Moisture-resistant expanded clay is also produced by modern industry. Granules of this material are coated with a special water-repellent composition. Although such expanded clay is more expensive than usual, it is best to use it for floor insulation, of course.
Backfill Technology
As with the use of mineral wool or expanded polystyrene, floor insulation is expanded with expanded clay according to logs using a fairly simple technology. The rough base on the lower edge of the beams in this case is not stuffed. It is recommended to install expanded clay when warming floors with a layer of at least 40 cm. It is especially important to observe this condition, of course, in the northern regions of the country.
Before filling expanded clay, the earth in the underground space should be carefully compacted. Next, the soil must be lined with a sand cushion. Although you can skip this step if you wish. Then on the soil or pillow you need to lay sheets of roofing material or a thick film. It is desirable to waterproof the earth under expanded clay in two layers. At the same time, waterproof material should be laid with an overlap on the walls and between the strips of at least 10-15 cm.
After the waterproofing is laid, you can proceed to the actual insulation of the floor with expanded clay between the logs. This procedure is usually carried out using large buckets. After the expanded clay is laid, a vapor insulator is pulled over it and the lag. The strips of this material, as with other types of insulation, are connected to each other using masking tape.
Useful tips for insulation expanded clay
Sometimes on the Internet you can read the recommendation to mix such bulk material when insulating the floor with concrete. Experienced builders do not advise doing this. No load in the floor with beams on the layer of such insulation during operation of the house will subsequently occur. When using concrete, the effectiveness of expanded clay as a heater, unfortunately, will significantly decrease.
If the soil under the house is rocky, before laying the waterproofing under the bulk insulation, it can, among other things, be poured with concrete screed. This will avoid damage to the roofing material or waterproofing film on the stones. The presence of gaps in such materials adversely affects the quality of insulation. In this case, a screed with a thickness of at least 2-3 cm should be poured over the ground under the logs. Kneading the solution for such a coating, since it will not be subjected to too much load, can be in the ratio of cement / filler as 1 to 4-5.