Floor insulation makes living in a country house much more comfortable. In addition, by following this procedure, the owners of a private low-rise building get the opportunity to save on heating in winter. Different materials can be used for floor insulation in country houses. But more often, all such a procedure is carried out using mineral wool, polystyrene foam or expanded clay. Laying such materials is allowed, of course, including between the lags.
Structure of floor on logs
On the logs, 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 buildings they are almost always made using boards and timber. The floors are assembled on logs, usually using this technology:
- the earth is carefully compacted and leveled;
- install retaining shortposts made of brick or concrete;
- spread columns with waterproofing;
- lay lags;
- plating the beams with boards.
This is the design of the floors on the logs in private homes. Their insulation, if necessary, is carried out with the preliminary dismantling of the plank coating and the installation of insulation boards or backfilling of expanded clay between the beams.
Use of mineral wool: advantages and disadvantages
It is with this material that floor insulation along logs in wooden or stone houses is most often produced. The advantages of mineral wool, private developers include primarily its low cost and ease of installation. For wooden houses, this material is just perfect also because it is fireproof.
Laying mineral wool slabs between the lags will not be difficult even for an inexperienced builder. But when installing such material, you should, of course, follow certain technologies. Some disadvantage of bas alt wool is that it is afraid of water. If such plates are saturated with moisture, they will lose their insulating characteristics.
Therefore, when laying mineral wool, it is imperative to use hydro- and vapor barrier materials. At the same time, it is worth buying only high-quality films for such plates. It is necessary to lay such materials with strict observance of the established technologies.
How to choose mineral wool
In principle, too dense material when insulating the floor along the logsthere is no special need to buy in a wooden or stone house. After all, the main load in such a ceiling during its operation in the future will fall on the beams themselves. In addition, very dense mineral wool usually retains heat worse.
However, too soft bas alt slabs for floor insulation in this case should not be used. According to the regulations, mineral wool with a density of about 30-40 kg/m3 should be used for laying between joists. These stoves are relatively inexpensive.
In most cases, bas alt material grade P-125 is used to insulate floors along beams. You can also buy cheaper plates P-75 for this purpose.
The thickness of mineral wool for floor insulation is chosen depending on the climatic characteristics of a particular area. For cold regions, they usually buy material for at least 150-200 mm. In warmer regions of the country, cotton can be used thinner and cheaper.
In cold regions, experienced builders advise using two layers of mineral wool to insulate the floor between the logs in a wooden or stone house. In this case, 100 mm material is usually purchased. At the same time, it is laid in such a way that the plates of the upper layer overlap the seams between the sheets of the lower one.
The width of mineral wool is chosen depending on the step between the lags. It is necessary to mount this material in the space between the beams by surprise. Most often, mineral wool slabs have a width of 80 cm. During constructionat home, in most cases, it is at this distance that the beams are located.
Insulation of the floor along the logs with mineral wool: installation technology
Because in the construction of country houses the beams are in most cases laid on posts, the distance from the ground to the floor surface is usually significant. Filling all this space with insulation, 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, the floor structure should simply be equipped with a support. To do this, bars 4-5 cm wide are stuffed on the logs along the lower edge of their vertical planes along the entire length. Next, shields are laid on them and fixed with nails or self-tapping screws, for example, from junk boards or plywood. Mineral wool slabs are laid on the resulting base in the future.
So that such an insulator does not dampen, when insulating the floor between the lags, before installing it, boards or plywood boards are carefully lined with a waterproofing agent. For this, you can use, for example, a thick plastic film or roofing material. It is best to lay such material in two layers.
At the next stage, slabs of mineral wool itself are mounted on the waterproofer between the lags. It is not necessary to attach this material to the base in any way.
After the mineral wool is laid, proceed to install the vapor barrier. This material is spread over logs and cotton wool with an overlap of 10-15 cm. At the same time, the joints are fixed using a painttape.
At the final stage of floor insulation, the flooring itself is mounted from boards or, for example, OSB boards. Then it remains only to lay some finishing material.
Some nuances
When insulating along logs in a wooden house or stone mineral wool, among other things, the following recommendations should be observed:
- logs before insulation must be cleaned of traces of rot and carefully treated with antiseptic, antifungal and preferably water-repellent agents;
- In cold regions, the top sheets of mineral wool are laid in such a way that they overlap the seams of the bottom layer by at least 10 cm.
The technology described above is used for floor insulation 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. The mineral wool itself and the vapor barrier in this case are mounted in the same way. The waterproofer is laid in the floor even before laying the log. At the same time, such material is mounted with an overlap on the walls of at least 15 cm.
Logs when using this technology in the event that the floor will not be subjected to too serious loads in the future, are not attached to the posts. In this case, the waterproofer will protect the insulation better.
Pros and cons of using Styrofoam and Styrofoam
With the use of such material, floors in country houses are usually insulated along the screed. However, sometimesfoam sheets are also used to insulate the floor along the logs. In this case, you can use not only dense and durable polystyrene foam, but even 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 bas alt slabs, foamed moisture is not at all afraid. The advantages of such heaters also include ease of installation. Installing Styrofoam is almost as easy as installing mineral wool.
In terms of environmental safety, such bas alt materials, according to many builders, are also superior. However, stoves of this type will not harm the people living in the house only if they are used at not too high temperatures. When heated, this material unfortunately begins to release toxic styrene.
The price of foam boards is higher than mineral wool. Insulation of a wooden floor along the logs with foam plastic or polystyrene foam will most likely cost more. This, of course, can be attributed to the shortcomings of such material.
Also, the minus of such plates is the fact that they can make moves and arrange nests for 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.
Floor insulation on wooden logs in a bath or sauna is most often also done using expanded polystyrene. Mineral wool is never used in such buildings. Versatility of application, thus, of course, alsocan be attributed to the pluses of foam boards.
Insulation of the floor along the logs with polystyrene foam: choice of material
Styrofoam floors in country houses today are extremely rarely insulated. This material, unfortunately, is very short-lived. Most often, private developers still use polystyrene foam to isolate the floor, including along the logs. This material has the best operational and technical characteristics and lasts a long time.
As with mineral wool, it is not necessary to use foam sheets that are too dense for laying between joists. Usually such material is mounted between the beams by no more than 15 kg / m 3.
For floor insulation in houses built in cold regions, 10 cm thick polystyrene foam is usually chosen and laid in two layers. For buildings erected in warm areas, it is allowed to use 15 cm material with laying in one layer.
Installation technology
The method of installing foam boards between joists when insulating the floor is not much different from the methods of laying mineral wool. Although expanded polystyrene is not afraid of moisture, it is still recommended to use hydro- and vapor barriers when using it. With prolonged dampening, the destruction of such material in any case will go faster.
Expanded polystyrene is mounted on logs, usually using this technology:
- support bars are stuffed on the beams along the bottom edge;
- mounted plank draft base;
- waterproofing in progress;
- the sheets of expanded polystyrene themselves are mounted;
- vapor barrier film being stretched;
- Finishing floor boards are mounted;
- Finishing sheathing or facing material is laid.
The use of this technology of floor insulation with foam plastic between the lags makes living in the house much more comfortable. Insulates rooms from the cold, such material is usually somewhat better than mineral wool.
Installation nuances
Unlike mineral wool, expanded polystyrene and polystyrene are inelastic materials. Therefore, after laying such plates, gaps usually remain between them and the beams. In order for the floor insulation along the logs with polystyrene foam or polystyrene foam to be as efficient and of 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, its parts that come out are cut off with a sharp construction knife.
Use of expanded clay: pros and cons
Most often, as we found out, in our time, mineral wool is still used to insulate the floor along the logs. Previously, expanded clay was used for this purpose in most cases. Such material is used to insulate floors from the cold sometimes today. The unconditional advantages of expanded clay include:
- cheap;
- excellent thermal insulationquality;
- light weight and therefore easy to transport;
- ease of installation.
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 insulation in the floor will last exactly as long as the house itself will be used.
Some disadvantage 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 it on sale.
Which expanded clay to choose
Used for floor insulation along the logs, this material is usually rounded with a porous fraction structure from 5 to 40 mm. Such expanded clay belongs to the group of gravel. Sometimes expanded clay sand is also used to insulate 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, the elements of which have uneven edges, is practically not used for backfilling between lags. This type of material is mainly intended for use as a filler in the manufacture of concrete mixtures. But if you wish, you can, of course, add a little crushed stone of this variety to the expanded clay mixture of gravel and sand.
Insulation of a wooden floor with expanded clay between the lags is a great way to increase the comfort of living in a house. But such material, as already mentioned, canabsorb moisture. Modern industry also produces moisture-resistant expanded clay. Granules of such material are covered with a special water-repellent composition. Although such expanded clay is more expensive than usual, it is, of course, best of all to use it for floor insulation.
Backfill technology
As with the use of mineral wool or expanded polystyrene, the floor is insulated with expanded clay along the logs using a fairly simple technology. The draft base along the lower edge of the beams in this case is not stuffed. It is recommended to install expanded clay when insulating floors with a layer of at least 40 cm. It is especially important to comply with this condition, of course, in the northern regions of the country.
Before backfilling expanded clay, the ground in the underground space should be carefully compacted. Next, the soil must be covered with a sand cushion. However, you can skip this step if you wish. Then, sheets of roofing material or a thick film should be laid on the ground or pillow. 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 strips of at least 10-15 cm.
After the waterproofing is laid, you can actually start insulating the floor with expanded clay between the lags. This procedure is usually carried out using large buckets. After the expanded clay is laid, a vapor barrier is pulled over it and the log. Strips of this material, as with other types of insulation, are connected to each other using masking tape.
Usefulexpanded clay insulation tips
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. There will be no load in the floor with beams on the layer of such insulation during the operation of the house in the future. When using concrete, the effectiveness of expanded clay as a heater, unfortunately, will decrease significantly.
If the soil under the house is rocky, before laying the waterproofing under the bulk insulation, it can, among other things, be filled with a concrete screed. This will avoid damage to the roofing felt or waterproofing film on the stones. The presence of gaps in such materials most negatively affects the quality of the insulation. In this case, a screed with a thickness of at least 2-3 cm should be poured on the ground under the lags. Mixing the solution for such a coating, since it will not be subjected to too much load, can be done in the cement / filler ratio as 1 to 4-5.
