Everyone understands that it is impossible to live in a room without arranging the floor. Whether it's a house or an apartment, you can't do without it. But do you need a rough floor in wooden house, not everyone knows. Why do you need additional expenses for its arrangement? Is it really impossible to do with a finishing coat? And what is meant by this name? This article is for those who want to figure it out and make a rough floor on their own.

What is a sub-floor?

The subfloor is a kind of base for the finishing coating, creating a horizontal flat plane for it. It serves to distribute the load on flooring.

A subfloor on logs is considered a classic roughing. This is exactly what is usually done in wooden buildings. For him, logs are laid on the base base with a certain distance from each other. On large areas provide a double frame system, the so-called crate.

In it, jumpers from a bar (crossbar) are installed between the lags. At the same time, the horizontal leveling of the surface of the logs is constantly monitored. A cranial block is attached to the lower part of the lag. On it, the sub-floor is laid from plywood or wood board. Subsequently, insulating material and waterproofing are laid between the logs.

Insulation and vapor barrier are laid on top of the rough floors. For the manufacture of a rough coating, chipboard or fiberboard or plywood is used.

Stages of the sub-floor device

And now more about how to make a rough floor with your own hands. There are two options for installing the lag: overlap or base. In any case, before equipping the subfloor, it is necessary to take care of the ventilation of the subfloor. It is enough for her to drill a few round holes in the corners of the house. Subsequently, they are covered with bars. Also, before starting work, the entire underground space is treated with an antiseptic. These measures are the key to strength and durability. wooden house.

Preparation of logs for construction

In fact, logs are bars from which the frame for the future floor is made. For them, boards made of wood of the second or third grade are used. Since usually such logs have uneven surface they must be prepared before use.

To do this, the side on which the finishing floor will be mounted must be leveled with an ax. It will not work to make the surface perfectly flat, but it is necessary to level it a little. Horizontality depends on it finishing coating... From above, the logs are covered with antiseptics.

Before laying the logs, grooves are made in the upper crown of the walls. The planed logs should lie exactly in these grooves, but with a distance from the end to the walls of 2-3 mm. Later, a soundproofing gasket is installed between them. In addition to the grooves in the beams, for long logs, an additional support is installed in the form of brick pillars. The distance between the joists depends on the thickness of the boards used for flooring. The thinner the boards, the more often the logs are located.

For boards with a thickness of 35 mm, the distance between the logs is at least 50 cm, 35-40 mm - 80 cm, more than 40 - 100 cm

Note! After installing the lag, their ends must be fastened. This is necessary so that they do not disperse during the process of laying the boards of the rough covering.

The surface of the base is leveled before work is performed, covered with crushed stone and compacted. Next, measurements and markings are made for the supports. Either a grillage covered with roofing felt, or the bars of the lower strapping can act as supports. In the first version, the mark is placed on the roofing felt, in the second on the uneven bars.

The horizontalness of the lag is checked not only relative to the ground, but also relative to each other. They should be on the same level. Maximum tolerance for 1 m2 no more than 1 mm

Support pillars are installed on the foundation, minimum dimensions which for one element is 40 × 40 cm. Its height must be at least 20 cm, with 5 of them above the ground. They put on the supports under the logs waterproofing material... It will protect the wood from mold. The logs are attached to the posts using corners and self-tapping screws with dowels. The same device has a rough floor in a brick house.

Fastening the timber

For support under the rough floor on the logs, a bar with a section of 50 × 40 mm or 50 × 50 mm is used. Attach it to the bottom of the log on both sides. In this case, it is necessary to take into account the size of the future insulation, which will be laid on the rough covering. It is more economical not to purchase ready-made bars, but to buy a 150 × 40 board and dissolve it into three parts. As a result, one board will turn out three bars of 50 × 40 mm.

Sub-floor laying

Perform a sub-floor of plywood or OSB sheets, Chipboard. It is advisable to use slabs with grooved ends about 20 mm thick. Application is allowed sheet materials 12 mm thick in two layers. To fix them securely along the entire perimeter, a crate of additional transverse bars is made to the lags. The subfloor boards are fixed with self-tapping screws with a pitch of 90-140 mm. If the floor is made of sheet materials, the joints should fall on the central axis of the additional beams.

Note! Some masters advise to use not for the subfloor quality material, but a junk board, slab or picket fence. This is due to the fact that the rough coating reacts to changes in humidity and temperature. And such a material is capable of deformation.

After finishing the installation work, proceed to the installation thermal insulation material and waterproofing. You should be very careful. Rough boards can break under heavy weight. Therefore, it is advisable to walk along the logs or thick boards thrown over them.

Results and video with an example of work

That's probably all, the rest is in your hands. The seemingly unnecessary waste on such a flooring arrangement will pay off over time. A layer of insulation, laid on the rough floor, will help save on heating costs. And this is a significant argument in favor of the sub-floor device. In addition, a high-quality subfloor is a guarantee of the durability of the finish coat.

Longevity and excellent aesthetic characteristics of the final flooring are provided by the subfloor in a wooden house, which is made according to different methods.

A rough base is understood as a special structure necessary to form the most even area for the finishing floor covering. Its second task is to provide uniform distribution floor loads. The rough base can be equipped in two ways:

1. Dry - lags are used.
2. Wet - the leveling structure is created by concrete screed.

Rough sub-floor

Among other things, the subfloor in a wooden house is installed in order to increase the thermal insulation performance of the dwelling. In timber buildings, the wet technique of arranging a leveling base is very rarely used. It is usually created using lag. In this case, the rough floor platform is mounted on the base or along the ceilings (thick beams or reinforced concrete slabs). Next, let's talk about how to properly make a preliminary floor using wooden elements.

Before starting the arrangement of the rough base, it is necessary to choose the method by which it will be mounted and to determine the amount of materials required. After that, a row of round holes should be made in the corners of a residential building made of wood. They will provide effective ventilation of the subfloor and increase the life of both subfloor and finishing floor. The holes will not spoil the look of your home. At the end of all the planned work, you simply disguise them with decorative ventilation grilles.

Then it is necessary to treat the entire underground space and directly the lags with an antiseptic composition. Laying the rough base on an unprocessed site is not allowed. You need to understand that various microorganisms can appear on the elements of the subfloor during the operation of the building. If wooden logs do not process, they will very quickly be destroyed by mold and mildew. And it is almost impossible to repair the preliminary foundation - access to it is either completely impossible or very difficult.

• hot resin - it protects both from the negative effects of moisture and from a variety of pests;
• solutions of VVK-3, KhKhP or MHKhTs;
• fluorosilicate ammonium;
• chlorophos - it is most often used as protection against insects;
• sodium fluoride.

Wood processing products

All of these compounds are safe for humans. They do not emit harmful substances and at the same time have the required indicators of wood water protection. Processing with their help should be done strictly according to the manufacturer's instructions.

Note! Subfloor boards should only be processed with back side... But on the logs themselves, crowns and beams protective compounds applied from all sides.

Additionally, it is recommended to treat the sub-base with fire retardants. Specialty stores now sell universal formulations, which simultaneously protect wood from fire, moisture and microorganisms.

For mounting the platform under the floor topcoat stock up on the following materials:

1. Wooden bars of the third or second grade - logs. In most cases, such products are characterized by a not very flat surface. Therefore, they need to be slightly tweaked. Your task is to make their front side (the one on which the laminate, parquet board or other covering will then be laid) more or less even. Such an operation is performed with an ax. Naturally, nothing needs to be done with logs made of first grade wood. Such products are in themselves very even.
2. Bricks for the construction of support pillars. The height of the finished supports should be at the level of 20-25 cm, and their dimensions are usually taken as 40x40 cm. The number of brick pillars is determined by the geometric parameters of a wooden house and its floor base. Supports are mounted on cement mortar.
3. Plywood or boards. With their help, the first and second rough layers are laid.
4. Polyethylene film or other waterproofing material. It is needed to protect the logs from decay.
5. Heat and vapor insulating material.

Installation of the platform under the floor finish

Also, the installation of the structure described by us is impossible without the use of fasteners. With brick supports, wooden logs are most often connected with 4x5, 5x5 cm bolts and steel corners.

How to make the floor correctly - instructions for beginner craftsmen

The design considered in the article can have two or one layers. If the beams are attached to the walls of a wooden residential building, the installation of a lag is mandatory. In such a situation, the distance between the individual beam products is quite large. If the distance between the beams is minimal, the leveling base is allowed to be made directly on them.

Scheme self-fulfillment installation works is this:

1. Install brick pillars(they serve as a support for the black base) or make a strapping of boards around the perimeter of the room. If used support elements made of bricks, roofing material must be laid on top of them.
2. Attach the logs to the base of the house. Fix them with bolts and corners made of metal (to brick supports) or (to a harness made of wood).
3. When installing the lag, leave 20 mm gaps near all wall surfaces. Thermal insulating material can be placed in these slots. With a small distance of the support of the logs on the base of the house (less than 10 cm), they are installed in the same way. And then they are pressed with a fairly massive bar. It is fixed tightly in the walls of the building. The walls of the house and the sections of the joints of the timber are measured, after which the corresponding incision is made. It is advisable to take its dimensions a couple of centimeters larger than those that you get as a result of measurements. Do not forget that the logs will expand slightly under the influence of moisture.
4. Install cranial bars at the bottom of the supports for the rough base. Then connect them with the lags on the sides. The geometric parameters of such bars are always taken smaller than the dimensions of the main elements.
5. Mount the boards on the beams. You do not need to attach them. The wood will expand during operation. Free placement of the boards will not interfere with this natural process.
6. Lay a layer of waterproofing on the floor base. The selected moisture-proof material (for example, plastic sheeting) should be fixed to the wall surfaces. On them, the waterproofer goes to a height that is equal to the height of all available levels of the feasible floor base (this figure also includes the finishing of the floor). Fasten the areas of connection of the pieces of film with each other with a construction stapler.
7. Lay a layer of thermal insulation. The height of the lag should be slightly greater than the thickness of the heat-shielding material. For wooden buildings, it is allowed to use any materials for

   Subfloor thermal insulation layer

   Next, cover the cake made with a vapor barrier material. He is also fixed on the walls of the building with a stapler. The joints of vapor barrier products are glued together with construction tape. If the heat-insulating material was laid precisely along the height of the lag, thin slats should be mounted on their sides. They will hold the insulation in place. As a result, you get a ventilation gap under the floor.

   Final work - laying plywood, boards, OSB-boards on a rough base. The installation of the second layer of the base is carried out in the same way as you installed the first part of the structure (leave gaps at the walls, place heat-insulating material in them, and so on). Fastening of boards, plates and sheets is carried out with a pitch of 10-14 cm using stainless self-tapping screws.

   As you can see, it is not difficult to equip a rough base with your own hands. Good luck with this business!

The concept of "rough floor" hides not just poorly processed boards, but a real "pie" of various materials which together form solid foundation for a clean floor. By the way, the subfloor does not have to be wooden; it can also be a concrete screed on the ground. The technology for arranging the subfloor includes a set of measures that provide hydro, heat and noise insulation of the base. In this article, we will look at how you can make a solid and reliable sub-floor, on which you can lay any finishing coating.

How to make a wooden sub-floor on the ground

V country house arrangement of the floor is a responsible and laborious task. A wooden floor on the ground can be made without restrictions. Even if you temporarily live in the house, when the heating is not working, the wooden floor serves for a long time without changes, since the underground is well ventilated through the vents in the foundation.

For wooden elements of the floor structure, it is necessary to select high-quality dried wood with a moisture content of no more than 12%. This is important, as a damp tree can "lead" during operation. For the rough floor in the house, conifers are chosen - spruce, pine, fir, larch. Resin-rich wood is less susceptible to rotting and the development of mold.

Also, wood for logs and subfloors must be treated with an antiseptic and fire retardant.

The underfloor of the wooden floor on the joists must be well ventilated. For this, air vents are made in the foundation, which are covered with a mesh with a cell of no more than 8 mm, so that mice do not get inside.

Base for wood floor

The construction of a wooden floor on the ground assumes that the floorboards will be laid on logs - longitudinal beams. Depending on the characteristics of the house, the logs can be laid on the support beams, a crown or on the support posts.

If the room is large enough, it will not be enough to fix the logs only with the ends on the beams, the structure will turn out to be fragile. Therefore, in the intervals between the walls, support posts are installed on which the logs will be laid. The step between the posts depends on the section of the lag. For example, if a beam of 150x150 mm is used as a lag, then the distance between the support posts should be no more than 80 cm.

How to make support pillars for logs:

• First, we make the markup where the lags will be located. We make notes on the support beams or the foundation of the house. Then we pull the cords through the entire underground. We pull the cords across the future lags at a distance of 80 cm or any other that is equal to the step between the posts. Support pillars will be located at the intersection of cords or ropes.

• In the places where we will make the support pillars, we dig a hole 40-60 cm deep, with sides 40 cm.
• At the bottom of the pit we tamp the soil, pour a 10 cm layer of sand, and then 10 cm of crushed stone. We carefully tamp each layer in turn. This will be our filling for the foundation of the column.
• We install a wooden formwork in the pit for pouring the foundation under a concrete post. If the supporting posts will be made of bricks, then the height of the foundation should be such that it rises 5-10 cm above the ground level. If the entire support post will be cast from concrete, then the height of the formwork should be such that the logs laid on the post are located horizontally.
• We insert a reinforcing frame inside the formwork, connected from steel rods of 6 - 8 mm in cross section.
• Pour concrete.

Important! If the entire post is poured from concrete, then it is necessary to control that the surface of the post is exactly horizontal and that all the posts are at the same level.

• After the concrete has completely dried, we cover the surface of the column with roofing material or glass insulation in 2 - 3 layers. Necessarily without sprinkling. We coat the surface and joints with mastic.

If you want to make support posts from bricks, then the masonry must be fastened with cement mortar. For a column with a height of less than 25 cm, the masonry should be 1.5 bricks, for a higher column, 2 bricks will be required.

After the concrete has dried, the formwork can be removed. For greater reliability, it is better to remove fertile soil from the underground. It must be removed to a depth of 20 cm. Instead of soil, it is advisable to add 10 cm of gravel and 10 cm of sand and carefully tamp with a vibrating plate.

Before starting the arrangement of the base, it is necessary to treat the beams, logs and sub-floor boards with an antiseptic. The logs can be laid directly on the crown or foundation and on the supporting posts, or you can first install the supporting beams on the posts, and then the logs from above across. Either option is correct. Only laying the joists across the beams provides a more stable and solid construction in the event that the distance between the lags is very small, 40 - 60 cm.

The section of the lag must be selected taking into account the thickness of the heat-insulating material that will fit between them. For example, if the thickness of the insulation is 150 mm, then it is necessary to take a beam with a height of 180 mm. It is always necessary to leave ventilation gap in 30 mm.

The step between the lags is selected taking into account the thickness of the boards of the future floor. More detailed instructions can be found in the table below.

Table 1. Step lag.

Consider laying a lag on support posts:

• We lay the logs on the foundation crown (support beams, foundation) and support posts. We control their even arrangement, horizontal. A sound absorbing material can be placed on the surface of the support posts under the logs. But this is not necessary, since roofing felt or other waterproofing material, which covers the surface of the pillar, springs well and hides sounds.
• If, nevertheless, a sagging of the lag is noticed somewhere, it is necessary to put wooden blocks on the support posts under the lags and fix them firmly. If the beam sticks out somewhere, then it can be cut off with a plane.

Important! The maximum permissible deviation in the evenness of the location of the lag is 1 mm per 1 m.

• We fix the lags to support pillars with mounting brackets. From the side of the wood, we fix it with self-tapping screws 50 mm long, and from the side of the concrete column, we tighten the anchor.
• The first to lay the so-called "lighthouse logs", which are located at a distance of 2 m from each other. Further, we will be guided by them.
• By analogy, we put all the logs and check their even location.

After all the logs are fixed, you can proceed to the arrangement of heat and waterproofing.

Thermal insulation and waterproofing of a wooden floor

Waterproofing and thermal insulation materials are placed between the logs. To fix them, you need to equip the base. This can be done in several ways.

Method 1. From the bottom of the lag, you can nail sheets of moisture-resistant plywood. This design will be as reliable as possible. To do this, you will have to work from the underground, which is not always possible.

Method 2. In the lower part of the lag, you can nail cranial bars with a thickness of 20 mm, from above you can roll from the boards. This work is more painstaking, since you will have to cut a lot of boards with a section of 15 mm and a length equal to the step between the logs.

You can choose the method that you like best. The main thing is to get a fairly solid foundation.

• We lay a layer of waterproofing with an overlap of 15 - 20 cm, glue the joints with construction tape.

Important! Be sure to use a superdiffusion vapor-permeable membrane. We need the waterproofing material to release moisture from the room, but not let it inside from the side of the underground. Therefore, you cannot use ordinary plastic wrap.

• On top of the film, between the lags, we lay a heat-insulating material. Chop roll material width equal to the step between the lags plus 1 - 2 cm so that the material fits into the gap between the lags.

Important! As a heater for a wooden floor, you can use mineral wool in rolls, slabs, basalt wool, you can blow out ecowool, sawdust. Styrofoam and extruded polystyrene foam must not be used. These materials are completely vapor tight, the wooden floor simply cannot breathe.

A ventilation gap of 2 - 3 cm must be left on top of the insulation.

Sub-floor laying

The sub-floor can now be laid in the house. There are several options for arranging rough flooring. As a material you can use floorboard 15 - 25 mm thick with minimal processing. You can also use a tongue-and-groove floorboard if finances permit. For subfloors, the price depends on the cost of the materials used. If you use thick solid board, then there is no point in laying a subfloor from a floorboard. Or you can lay sheets of plywood, and on top you can lay the finishing flooring.

Subfloor from floorboard:

• We start laying from the wall. Cut off the spike and attach the board to the wall, leaving a 2 cm gap.

Important! The indent from the walls is required, since wood is a plastic material, gaining moisture, expands, and dries up, shrinks. The gap will provide an unobstructed opportunity for the wood to expand and shrink.

• We fix the board to the logs. From the side of the wall, screw the screws directly into the board, then this place will be hidden by the baseboard.
• From the side of the thorn, screw the screws into the thorn at an angle of 45 degrees.
• We move the next board close to the first. We insert into the groove of the first board.
• We screw a self-tapping screw into the groove of the second board, fixing it to the log.
• All subsequent boards are laid by analogy.

Important! If the boards are the same length as the room, then they can be laid exactly parallel to each other. If the boards are shorter than the room, then they must be stacked with an offset - apart.

The last board is fixed so that you can hide the caps of the screws under the skirting board. On this, the rough floor is ready. The main thing is to tightly fit the boards to each other. You can lay a floor covering on top.

How to make a wooden sub-floor on a concrete base

In apartments with concrete slabs you can also make a wooden floor. The lags are laid on concrete base, but for this it must be even. A height difference of several centimeters is unacceptable. Therefore, the option when under the bending logs is placed wooden blocks does not fit. Over time, the linings will dry out and deform, from which they can easily fly out and the floor will begin to creak.

Substrate preparation: hydro and sound insulation

Before laying the logs on the concrete floor, the base must be leveled. To do this, fill in cement-sand screed... Further work can be continued only after the concrete has completely dried, i.e. a month later.

On the surface of the concrete screed, we lay a waterproofing film with an overlap of 15 - 20 cm, glue the joints with tape.

We put noise-insulating pads under the logs. To do this, you can use cork materials or foamed polyethylene with a thickness of 1 - 4 mm. The lining under the logs is needed in order to dampen the impact noise.

Laying logs on concrete

It is advisable to use a bar with a length equal to the length of the room. If this is not possible, then you can take a shorter timber and connect it to the end. In this case, the joints should be staggered.

• We lay the logs on the prepared base.
• We check the horizontal position of the lag.
• We fix the logs to the floor using corners. Do not forget that the corners themselves are attached to concrete floor anchors.
• After laying and securing all the logs, we lay the insulation between the logs in the same way as in the case of the floor on the ground.

Do not forget to leave a ventilation gap of 2 - 3 cm.

Installation of the subfloor

On top of the lag we lay a rough floor. As mentioned above, it can be plywood, or maybe a floorboard.

Consider the option of arranging a subfloor made of plywood:

• We take a sheet of moisture-resistant plywood with a thickness of 22 mm.
• We lay a sheet of plywood on the logs and fix it to them with self-tapping screws in 15 cm increments.
• We arrange the plywood sheets in a checkerboard pattern. To do this, some of them will have to be cut.
• It is impossible that the joints of the plywood sheets are in one line.

Do not forget that there should be a gap of 2 - 3 cm between the wall and the subfloor. On top of the plywood base, you can lay such floor coverings: laminate, linoleum, ceramic tiles, vinyl tiles, parquet, parquet board, massive board.

Installation of rough concrete floors on the ground

It is not always possible to pour a concrete floor in a private house on the ground. There are certain restrictions. At first, groundwater on the site should be low enough - at the level of 4 - 5 m. Secondly, the soil must be stable, not mobile, otherwise the concrete floor may collapse. Thirdly, people must constantly live in the house, or it would even be more correct to say that it must be heated in cold period of the year. If all conditions are met, you can safely fill in concrete slab on the ground.

Earthworks and foundation preparation

First of all, it is necessary to outline the "zero" mark - the level of the future floor. You need to navigate along the bottom of the doorway. All walls must be marked so that in the future it is clear how long to pour concrete.

• Floor on the ground - a multilayer structure 30 - 35 cm thick.To equip it, remove upper layer soil until the height from the zero mark to the bottom of the excavation is equal to 30 - 35 cm.

Important! If the soil level is below 30 - 35 cm from the floor level, then it is necessary to level the soil surface, tamp it, add sand to the required level and also tamp it thoroughly.

• We tamp the foundation of the pit.
• Pour a 10 cm layer of crushed stone and tamp it carefully. If the thickness of the backfill is difficult to control, then we drive several pegs into the ground with the desired mark. After leveling and tamping, the pegs can be removed.

• Pour a 10 layer of sand, pour it with water and ram it too.
• On top we pour a small layer of crushed stone with a fraction of 40 - 50 mm.
• Sprinkle with sand, forming a thin layer, tamp it carefully.

Important! If suddenly sharp edges of crushed stone fractions are observed on the surface of the base, it is necessary to unfold the pebble and put it so that there are no sharp corners anywhere.

At all stages of the filling, it is necessary to monitor the horizontal position.

Waterproofing, thermal insulation, reinforcement

• We lay a waterproofing material on the surface of the base - a polyethylene film with a density of 200 microns, roofing material or glass insulation. The main thing is that the material is not damaged on the edges of the rubble.
• We put the waterproofing material on the walls up to a mark 2 cm above the floor level. We lay it with an overlap of 10 - 15 cm and glue it with tape.

• At this stage, you can lay a durable thermal insulation material. For example, extruded polystyrene foam or basalt wool in slabs, perlite or expanded clay are suitable. You can also thermal insulation layer place higher, on top of the concrete base.

• The concrete floor must be reinforced. To do this, we use a metal mesh with 10 cm cells.
• We install the reinforcing mesh on supports 2 - 3 cm high so that the mesh is completely inside the concrete.

Installation of formwork and guides

To maintain the horizontal level of the floor, it is necessary to lay the so-called "beacons" or guides. For these purposes, you can use round and square steel tubes, wooden blocks. We arrange them in increments of no more than 1 m. We fix them with a thick cement mortar... Also, their height can be controlled by pouring more solution under the guides.

Between the guides, we install the formwork for pouring the floor. This is not necessary, but it makes the task of manually pouring the concrete floor much easier.

We treat the guides and formwork with oil or working off, so that after pouring they can be easily removed.

Rough floor screed - pouring concrete

It is necessary to pour the concrete floor in the house in one or two passes. If you take long breaks, then the foundation will turn out to be fragile.

• We start pouring concrete from the corner opposite the front door.
• Fill several cards at once, then level them with a shovel.
• We compact the concrete with a deep vibrator.
• Align the surface using a rule. Set the rule on the guides and pull it towards you. Excess solution is distributed among cards in which there is not enough solution.
• We take out the cards and fill the voids with concrete.
• When the entire floor is filled with concrete using this technology, it must be covered plastic wrap and let dry for a month.

For better drying of the concrete sub-floor, its surface must be moistened with water.

After the concrete is completely dry, the floor can be screed clean and the floor can be laid.

Making a rough floor with your own hands is a very important task, because a solid foundation is much more important than a finishing coating. For example, in an old house, you should not lay new flooring on top of an old sub-floor, unless it has been overhauled.

Not a single residential building allows even the thought of living in it without flooring, and in any construction manual you will find more than one chapter devoted to this topic, as they say clearly and without words. But a rough floor? How necessary is it? Are the costs of its arrangement worth the indicators that subfloors provide? Let's try to figure it out together.

Subfloor refers to the subfloor, subfloor, any floor covering, be it laminate, parquet or linoleum. A rough floor is also understood as a selection, the bottom layer of double floors, holding insulation and vapor barrier. The subfloor is also recognized as the lower plank flooring, laid diagonally and used when using 25mm boards and a sparse installation of logs. Such a broad interpretation of the concept of a rough floor gave rise to caution in operating this term, people simply do not understand what it is about.

A sub-floor, as a backing, is usually laid for laying laminate, parquet or roll coatings- linoleum, carpet, etc. The point is the distribution of the point load on the coating and the leveling of the floor relief. Leafy wood materials here will be the simplest and effective remedy... As a basis, plywood, fiberboard or chipboard are mainly used, as the most affordable and technologically advanced materials, but you can also equip plank floors by laying them directly on the beams. There are many options, but the performance of the flooring, under which the foundation is made, depends on the quality of the base, the subfloor.

Double floors, or they are also called insulated, also imply the arrangement of the subfloor, but it is needed mainly to support the insulation. This does not mean any minimalism of costs and time, no, on the contrary, here it is necessary to accurately withstand the technology of arranging the floors, since negligence can reduce the service life of the entire building. First of all, it is necessary to provide ventilation of the underground space. Therefore, "three times" make sure that the ventilation openings are working so that they will not be blocked by the supports. Make sure the underground soil is dry and if it isn't, your home's waterproofing needs to be redone or reinforced. Good concrete blind area around the perimeter of the house, clay castles along the foundation, roofing material, roofing felt and other materials must prevent moisture from entering the underground space. Remember how in the recent past, the appearance of white mold in the house forced the neighboring buildings to be burned, since all buildings could rot and collapse. Antiseptic treatment lower rims at home and the entire "lower" space - the next preparatory stage double flooring.

Under the logs or beams, regardless of the material of the supports, it is necessary to put roofing material or any waterproofing that prevents them from absorbing underground moisture. Already on the lags, the finishing floor is laid, and the rough floor is laid on the shoulders, the cranial beam, nailed or selected in the beam. For flooring, you can use a slab, a waste board, a picket fence, any material that can hold the insulation. You cannot just nail boards, since subfloors are the first to react to temperature and atmospheric changes and must be able to deform and thereby damp vibrations. There is also a way to lay the subfloor in the groove of the beam, but with any technology, the floors must be in different levels... Sub-floor, free space, final floor. It is this void that is filled with insulation, which provides thermal protection for the floors. But before laying the insulation, the subfloor is additionally treated with an antiseptic against decay, up to the use of engine oils, and a vapor barrier is arranged. It is best to take mineral wool as insulation, but any other will do. synthetic insulation, which practically does not rot. Insulation can also be taken loose, for example expanded clay or polystyrene, or even solid - polystyrene. By the way, in the old days, when they didn’t know Isover and Mineral Plates, they used sand or slag soaked in lime. Leave three to four in the corners ventilation holes, and warm floors will be so for many years.

Quite often, during construction, it is necessary to save a lot and lay the logs sparsely, and do not insulate the floor if the landing is low and the blockage is powerful. Here the subfloor flooring from a thin raw board, laid diagonally to the joists, comes to the rescue. For a finished floor, you can also use a board thinner than the standard, since the total thickness of the floor will be normal, and due to the intersection of the fibers, the effect of plywood is achieved, which eliminates the deflection of the floor. It is good to equip such floors on floor slabs, since they allow flooring without supports and even without lags.

There are, of course, many options, but in many respects it is necessary to be guided by the climatic and building traditions of your region, since they have been repeatedly tested by time and have logical reasons for their application.

Laying a sub-floor is a laborious operation, but absolutely necessary. The device of the lower floor of the house serves as its basis and is connected with the foundation. The subfloor serves as an intermediate link between the foundation and fine finish while performing a number of specific functions.

1. Subfloor as a structural element of the house

After strapping the foundation, first of all, the lower floor of the house is installed. On it you can carry out further work on the installation of walls. This is especially true for the construction frame house using frame-frame technology, and laying bricks, wall blocks from the inside requires a solid foundation under your feet. In addition, the bottom ceiling performs a number of other functions, being essential element building.

Sub floor:

1. Distributes all loads to the bottom floor, such as weight load-bearing walls and partitions, all people, furniture, household appliances and appliances
2. Serves as the basis for work on the assembly of the frame and the construction of walls
3. It is the basis for the finishing floor
4. Is a component of the overall shell of the house, protecting it primarily from low temperatures

Obviously, all of the above functions of the subfloor impose special requirements for its installation, such as strength, surface evenness, resistance to atmospheric influences.

2. Types of floors

The main reason for installing various designs sub-floor is the difference in the type of construction of the houses themselves. The house can be stone, block, built of logs or thick timber, frame. Under Various types houses can be mortgaged different types foundations:

• Slab
• Tape
• Columnar
• Pile screw

The deepening of the foundation and its strapping may also differ slightly. However, there are some common features and features of the device of subfloors for all types of structures. In many cases, the subfloor is based on strapping beams that receive and transmit all loads from the floor directly to the foundation.

In accordance with their function, subfloors are composed of several layers responsible for each of them:

1. The base of the floor is either soil or floor elements
2. The underlying layer is a layer of gravel, sand, slag, expanded clay, etc.
3. The base for the coating (screed) is a monolithic leveling layer
4. Hydro and thermal insulation layer
5. Floor covering itself

Sub-floors are classified into three main types:

• By lags
• On beams
• On the ground

The difference in the types of subfloors lies in the way they are laid, which is evident from the name.

3. Preparation for the installation of the subfloor

If the foundation of the house does not provide for a basement, then the soil serves as the basis for laying the sub-floor. It must be prepared accordingly for the sub-floor.

The grass is harvested, various construction garbage and vegetable soil. An important point: you need to dry clay and loamy soils as best as possible, so they can contain a lot of moisture in the base. It is also impossible to use soils with an admixture of snow and ice.

The site is then carefully leveled. If necessary, soil can be poured into the holes. After adding soil, it is distributed in an even layer and tamped with manual or mechanical rammers.

4. Laying the subfloor on the joists

The device of the floor along the logs is a fairly popular method.

In this case, it is made wooden frame, which is laid on a strapping beam or other specially made supports. The logs themselves are a bar or a thick board, sometimes placed on the edge.

In this case, the floor height should be insignificant - so that there is no danger of sinking to a great depth. The distance from the floor to the log should not be more than 25-30 cm.

With a significant width of the room, the lags will have long length, and it is not enough to lay them only on the external strapping beam. In this case, additional supports are placed under the lags. There are several ways to arrange supports for logs.

The base is concreted and a thick board is laid on it, which serves as a crate for installing the lag. This method is especially well suited for low basements above the ground. If the distance under the floor is large 15-20 cm and the floor is not concreted, columns are installed under the boards of the lower sheathing, with a step of about 80 cm. The installation of the columns can be done as follows:

1. Pits come off, slightly wider than the cross-section of the columns (35-40 cm)
2. Concreted so that the upper base protrudes slightly above the ground.
3. Brick posts are laid out.

Usually it is enough to lay out the posts in two bricks in two layers, perpendicular to one another. You can completely make the posts of concrete, but then you need to build a high formwork.

The height of all columns should be displayed in one plane. This is already controlled when the foundations are laid for them. If necessary, the height of the columns is adjusted with various substrates: wooden spacers are installed between the surface of the boards and the logs, the dimensions of which are about 20-25 cm in length, 10-15 cm in width, and the thickness is about 3 cm. They correct the horizontal plane of the log. Thin sheets of plywood are usually used for fine adjustments.

On top of the posts, you need to lay a layer of waterproofing, for example, from roofing material.

The distance between the joists should not exceed 0.5 m. A small gap should be left at the walls, taking into account the deformation of the wood.

On top of the log for the device of the finishing floor, you can fix plates of durable material - OSB or thick plywood. It is recommended to do this "sprawling", that is, the next layer of plywood or OSB is slightly displaced relative to the previous one.

If necessary, the cavities between the lags can be covered with insulation. It can be expanded clay or mineral wool- depending on the degree necessary insulation at home.

5. Floor on adjustable joists

V recent times acquires a way to install the lag on adjustable stands. It is plastic screw supports, sufficiently strong and lightweight. They are equipped with a square base, which is placed on a rigid base and a screw, adjustable in height. With their use, you can quickly equip the subfloor, besides, it will not come into contact with the base, it will be well ventilated, and therefore the need for waterproofing disappears.

The procedure for installing such lags is as follows:

1. Holes are drilled in the log boards - with a step of 50-80cm
2. The lag is installed in the right place
3. The support is attached to the base
4. Racks are twisted to the required level

6. Sub-flooring on beams

The next way to install a sub-floor is to install it on beams. Here, the main structural element is wooden beam... It is made from a bar rectangular section... To determine the cross-section of the timber, all load characteristics on the base of the premises of the first floor are taken into account. In order not to use a heavy, thick timber with which it is physically difficult to work, you can use double boards or boards installed on the edge. A good option would be to use hewn logs.

The load on the beams is calculated from a number of parameters that we mentioned above. It is believed that the total load from the weight of people on furniture, fittings, etc. can be about 400 kg per 1 m2 of floor area.

Span length, m	Installation step, m
	0.6 m	1.0 m
3	75x200mm	100x175mm
4	100x200mm	125x200mm
5	125x200mm	150x225mm
6	150x225mm	175x200mm
7	150x300mm	200x275mm

The beams are installed parallel to each other. If the room is more than 6 meters wide, additional supports must be installed under the beams. These can be posts, the installation of which was described above.

The beams are fastened directly to the walls. A hole is cut in the wall, corresponding to the cross-section of the beam, and the beam is laid in it with its end. For isolation from external influences this hole is filled with tow. The installation depth of the beams into the walls depends on the cross-section of the beams. The thinner the beams, the deeper they should go into the holes (up to 100-150mm).

Often, the sub-floor crossbeams are elements of the lower foundation piping.

7. Laying the floor on the ground

In many cases, especially if the height of the floor is low, it is laid in the "on the ground" method. In this case, you do not have to spend a lot of expensive lumber.

Consider this way in detail. It consists of several stages:

1. Base leveling
2. Backfilling with a layer of sand 10-15 cm at a moisture content of 7-10%
3. Compaction of sand
4. Backfilling of crushed stone and gravel with a thickness of 8-20 cm at a moisture content of 5-7%
5. Laying an adobe-crushed stone or adobe-gravel layer with a thickness of about 10 cm
6. Compaction of this layer and the appearance of moisture on the surface
7. Pouring with concrete mixture

As a result, after hardening, we get a flat, hard surface on which you can immediately lay the finishing floor. Sub-floor layers for better fastening and the solidity of the screed is reinforced, as a rule, reinforcing mesh... It is convenient to insulate such a floor with expanded polystyrene plates.

8. The device of screeds

The top layer of the subfloor on the ground is called a screed. Ties are made from cement-sand mortars... The main purpose of the screed is to create a perfectly flat surface for laying the finished floor. To bring the plane out, so-called beacons are installed. These are, as a rule, slats with a thickness selected for the creation of a plane. The mixture is applied to the floor and accelerated to the height of the slats.

The joints of the screed to walls and partitions must be waterproofed. The surface is continuously leveled during the laying process, as the concrete tends to settle.

Work on the creation of screeds must be carried out in warm time years since optimal temperature air not lower than 15 degrees. It is recommended to apply a self-leveling layer on top of the main screed (its thickness is about 5-10 mm) by the pouring method. For this, there are a lot of different mixtures on sale.

The final stage of the screed is its priming and waterproofing. Before applying primers, the surface is cleaned and primed without gaps.

9. Conclusion

The arrangement of subfloors is a rather laborious process that requires adherence to all technologies, accuracy and well-known craftsmanship. In the simplest cases, you can do it yourself, but it is better to turn to professionals - the structural strength of the building, the evenness of the surface and its suitability for finishing as well as adequate insulation and waterproofing of the entire house.

The specialists of the "K-DOM" company are ready to perform work on laying floors, both rough and final, in compliance with all requirements. The work can be performed both separately and as part of the construction of turnkey cottages.