Do-it-yourself subfloor in a wooden house - instructions. Do-it-yourself subfloor made of wood and concrete Subfloor in the house

The durability of the finished floor covering also depends on the quality of the base preparation. It is for this reason that laying the subfloor plays such a significant role. The material used during installation must ensure evenness finished design and be strong in compression. Modern technologies offer several options for arranging subfloors using different materials.

Types of subfloors

The subfloor in cross-section resembles a layer cake:

Base. It is he who bears the entire burden.
Layers of hydro, heat and sound insulation.
Screed.
Rough coating.

Not every owner can build something like this, however, you can make a subfloor with your own hands in different ways. Fortunately, there are several options for its arrangement.

Wet floors

The most popular methodology. Its implementation does not require special skills or high costs. The screed is carried out using gypsum or cement-sand mortar. Most relevant in houses with slab floors. The screed is poured onto the layers of thermal insulation. The top of such a floor must be leveled and dried, and only then covered with the final finishing layer.

There are three main types of wet screed floors:

Single layer. Used to eliminate defects in slabs, usually with differences of up to 1.5 cm.
Double-layer and multi-layer. They are used when it is necessary to level out significant dissonance in heights (up to 12 cm). It’s simply not possible to eliminate them in one layer.

Pouring the base is a great way to create the perfect surface for laying carpet, laminate or linoleum.

The positive qualities of a wet screed include: moisture resistance, fire resistance, strength and relatively small thickness. The cost of the material is affordable: $1-3 per kilogram of the mixture.

Dry floor

To minimize the installation time of the subfloor, use a dry screed. Solutions practically do not participate in the process of its formation. For this reason, the screed does not require long drying. Participates in the creation of the “pie” insulating material, sheathing and wood flooring. During installation, ventilation gaps are created.

Important! Screed under ceramic tiles must be treated with a primer. Failure to do so may result in the coating peeling off.

Prefabricated floor

We are talking about a dry screed. It is mounted on top of slabs or flooring with boards. A prefabricated floor is a structure made of rolled, sheet materials and dry backfill. The “pie” usually consists of screed, thermal insulation materials, joists and dry mixtures. A subfloor is installed on top.

Prefabricated floors are different high level soundproofing and serve as a base for most finished floors. They are almost 2 times lighter than wet screeds, but have a decent thickness, so they are not suitable for thin roll coverings.

Floors on joists

This type subfloors are most often found in older homes. The logs level and greatly facilitate the installation of a wooden floor, and also prevent the weakening of the load-bearing beams.

Arranging floors on joists seems quite simple, but it cannot be done without proper preparation. It is impossible to work with them without knowing all the subtleties.

It is not permissible to level the joists using wooden wedges and wood chips. Such a structure is not viable and after some time the floor begins to creak and sag. To level, sand is poured under the joists or the material is trimmed.

Antiseptic treatment and ventilation increase the service life of the frame. It is covered with slabs or sheet material on top, and to reduce the reduced noise index, polyethylene foam or fiberboard can be laid under the logs.

Adjustable floors

These floors are supported on the floor slab through threaded posts. They help raise the finishing coating to a height of up to 7 cm (if we are talking about plywood) or up to 22 (using logs). To create a subfloor, beams, skull beams and boards made of coniferous wood, usually of a lower grade, are used.

Subfloor materials

To correctly answer the question: how to make a subfloor, you need to decide what materials are needed for its arrangement.

The base is assembled from the following components:

Bricks. They are used to create pillars that are placed on cement mortar.
Metal corners and bolts. The logs are attached to the brick pillars.
Waterproofing. Choose a material that can prevent rotting.
Insulation. Lay on the bottom layer of the rough base.
Boards or slabs. Used for flooring.

Of course, these are not all the necessary elements. Their variations are due to the variety of types of rough coating and the wishes of the owner. The quantity is calculated based on the size of the building premises.

The lifespan of a floor directly depends on proper preparation And positive qualities materials included in its composition, including coatings.

Gypsum fiber boards

GVL and GVLV create a perfectly even base for finishing coating. Usually they are laid in two layers, fixed with glue. These slabs are usually used for leveling over expanded clay backfill or to create a heat and sound insulation coating. They are also suitable for laying over old subfloors. The only thing that should not be done is to combine GVL (GVLV) with lags. In this combination, the material cannot withstand local loads: even furniture legs can break the floor.

The base is suitable for almost any finishing surface: laminate, carpet, tiles, linoleum, cork or parquet. To protect the subfloor from the influence of possible leaks, you need to treat the slabs with a water-repellent compound.

Moisture-resistant chipboard

The material can withstand heavy loads (we are talking about the idea of high-density chipboard) and allows you to form a fairly even base. Due to its increased strength, it can be laid both on backfill and on logs.

Chipboard has good thermal and sound insulation properties. Typically, slabs, like drywall, are fixed with glue. They are laid in two layers, not forgetting about treatment with a water-repellent compound.

Important! Chipboard is best used in dry rooms and covered with carpet, parquet or linoleum. For additional sound insulation, the slabs are covered with technical cork.

Cement particle board

The material has excellent characteristics:

High strength;
Environmentally friendly;
Water resistant.

DSP does not burn and is not afraid of even serious leaks. The market offers slabs with a thickness of 1-3.2 cm. They are laid on the backfill or on frame joists, laid in two layers (the top one is treated with a waterproofing or water-repellent compound).

DSP is excellent for laying parquet and laminate flooring. The only drawback of the slabs is minor deviations in thickness at the joints (up to 2 mm). In this case, it is unacceptable to cover the surface with cork or linoleum without preliminary preparation grounds. Defects are eliminated by sanding and putty.

Moisture-resistant plywood

Multilayer plywood has many variations in thickness (from 0.3 to 3 cm) and cost ($2.7-39). Thanks to high strength It is often laid on frame joists, but just as often it is laid directly on a concrete base under parquet or laminate.

Subfloors in wooden buildings have their own constructive nuances, can be laid in several ways depending on the architectural characteristics of buildings.

Type of subfloors	Technical features and brief characteristics
	More often used as bases for finishing coatings: glued boards, piece natural parquet, different kinds laminate, linoleum, soft coverings. The main requirements for such structures are a flat and solid base that can withstand maximum design loads. For production, OSB boards, plywood, and planed boards are used. To protect the structure from the harmful effects of moisture, traditional or modern materials. Such floors are recommended for use during the construction of interfloor ceilings.
	The floors are installed under the joists on special cranial bars. There is a space between the joists and the finished floor into which insulation can be installed. Small pieces and waste are used for production, which makes it possible to reduce financial losses.
	The most economical and reliable method of constructing subfloors. Taking into account the mounting location, the bases can be insulated or under finishing flooring. Distance between load-bearing beams selected depending on the performance characteristics of the finishing coating.

When choosing a specific option, you need to take into account the purpose of the building, number of storeys, materials and technologies used.

General requirements for subfloors

Regardless of the type of structure, building codes require the following activities.

Fire protection. All fire-retardant materials are divided into two groups according to their resistance to fire. The first group is used for wooden houses With stove heating. Available in implementation a large assortment solutions, impregnation is done with a pneumatic spray gun or paint brushes. Required condition– lumber must be dry. The number of layers is determined taking into account the purpose of the wood.

Protection from putrefactive processes and biological damage to wood. It is recommended to carry out work using effective antiseptics; all of them reliably protect lumber from premature destruction due to high humidity. The disadvantage of such materials is their release into the air. chemical compounds. True, the concentration is considered safe for residents. For those who do not want to risk their health, there is completely safe way lumber protection – impregnation with natural technical oils.

Important. All impregnations and treatments must be carried out before laying the lumber, and not after. One more nuance - great attention should be paid to the ends, they are most susceptible to moisture. Fresh dust and ends are subject to additional impregnation.

It is mandatory to have vents to ensure natural ventilation of wooden structures. No impregnation will save the wood if it is not constantly ventilated. The parameters of the vents are specified in SNiP 01/31/2003; the diameter and location of the holes depends on the area and height of the underground. Protection of the underground from penetration of rodents into the openings is done with metal gratings; the geometry of the vents is not regulated.

Practical advice. Be sure to check the effectiveness of natural ventilation; if it is not there, the subfloors will not last the expected amount of time. To check, you can use smoke or open fire. If there is no visible air flow, measures should be taken immediately to improve the performance of natural ventilation.

Fulfillment of requirements building codes guarantees long-term and safe operation of floor coverings. As an example, we will look at two methods for arranging subfloors.

Subfloors on load-bearing wooden beams

The beams are laid on a foundation strip or strapping beam. There is no fundamental difference between the two methods; it all depends on the chosen method of building a house. A prerequisite is that between wooden structures and concrete elements there must be reliable waterproofing, most often two layers of roofing felt are used. This is the most cheap material, providing reliable water protection. In addition, the timber must be treated with any antiseptics.

The beam must lie strictly in one plane; installation is done using a level. Round logs need to be cut off on both sides with an axe.

Advice. If you have no experience working with an ax, it is better to purchase ready material. But keep in mind that in terms of strength it will be inferior to hewn round timber, but in cost it is significantly higher. The subfloor is attached to the lower base of the beams; the flooring will be made of OSB. But if you wish, you can use any available materials, and not just wooden ones.

Step 1. Unscrew the beam fastenings. The bars are screwed to the harness using metal corners and long screws. The subfloor is installed only on pre-exposed beams; therefore, their dismantling is required.

Step 2. Carefully remove the beam from the mounting slot and turn it face down.

Step 3. Attach the OSB strip to the bottom of the beam with self-tapping screws or ordinary nails. The width of the strip should be 10–15 cm greater than the width of the flat area of the beam.

Important. The length of the screws should be ≈ 70% greater than the thickness of the plate, otherwise the fixation will not be reliable. This rule applies to all cases of fixing structures to each other.

When tightening the screws, press the drill with great force; the plate should not lift. When screwing in, inexperienced builders do not press the screws with sufficient force; the screw rotates slightly in the slab, causing a gap to appear between it and the beam. This greatly worsens the parameters of the subfloor.

Using the same technology, attach the sheets to all beams. If you do not have OSB, then you can use low-grade boards, including unedged ones. The main condition is that the bark must be removed. The thickness of the boards is ≈ 10–20 mm, the width does not matter. The subfloor has no noticeable loads; its task is to serve as a basis for laying insulation materials, and they are light in weight.

Step 4. Place all dismantled beams in place, secure them with metal squares and self-tapping screws. Check the position again, adjust them with shims if necessary various thicknesses. Never use lumber for underlays; they will certainly sag over time, which will disrupt the horizontality of the final floor covering. For linings, use durable, moisture-resistant ones. Construction Materials. Another important condition– the dimensions must be equal to or larger than the beam areas, which will allow the loads to be evenly distributed.

Step 5. Place the pieces of OSB in the prepared areas. When preparing sheets, there is no need to take exact dimensions; small gaps not only simplify the laying process, but also improve natural ventilation subfloor. In this way, by the way, you can save lumber.

Practical advice. Never walk on a subfloor; it is not designed to carry that much weight. When laying the last row, you should walk on the beams. If you wish, you can foam the joints of sheets and beams, but this operation is not considered mandatory. We have already mentioned that wood must be ventilated. As for the increase in heat losses, it is insignificant.

Step 6. Lay a vapor barrier, never use ordinary polyethylene film for this purpose high pressure. The fact is that it does not allow steam to pass through, and as a result, water will always accumulate in the heat insulator; it is in the insulation layer that the condensation point is located. High humidity significantly reduces the heat saving performance of mineral wool and has a very negative effect on wooden structures. Moisture must be constantly removed from the insulating layer, and only modern membranes can provide this.

Fix the vapor barrier to the beams with a stapler, the overlap of the layers is at least 10 cm, the joints should be carefully sealed with tape.

Step 7 Lay a layer of thermal insulation. For these purposes, you can use rolled and pressed mineral wool or polystyrene foam. It is advisable to use mineral wool. Why?

Mineral wool does not burn. Due to these fire resistance characteristics, it is also used as a fire barrier.
The material is completely safe. Mineral wool is made from basalt, which is a natural glass of volcanic origin.
Basalt wool is not afraid of rodents, which is very important for wooden houses.

Pressed and rolled cotton wool is produced standard sizes, it is recommended to take them into account during the installation of beams. The width of the wool is 60 cm, the distance between the beams is recommended ≈ 55–58 cm. Due to these dimensions, a tight fit of the insulation to the structures is ensured, reducing heat losses, the indoor microclimate improves. In addition, there is no need to cut the sheets, which speeds up work and reduces waste.

The thickness of the insulation is at least 10 cm. Make the second layer offset to cover the joints. If a wooden house is built in a cold climatic zone, then the insulation layer must have a thickness of at least 15 cm.

Step 8 Cover the thermal insulation with a waterproof membrane. The technology for installing it is no different from the algorithm for installing a vapor barrier membrane.

Step 9 Nail slats approximately 2 cm thick to the beams; they will serve as joists.

Practical advice. Professional builders strongly do not recommend laying the floor directly over the beams. The bars ensure ventilation of the finishing coating, and this is necessary regardless of the type of floor.

Further work depends on the technology you choose and the finishing materials for the floor covering.

Installation of subfloors along joists

These options are used in wooden buildings, being built according to the most modern technologies. The floor will be made of glued moisture-resistant plywood 2 cm thick, the flooring method will be on joists.

Step 1. Measure 120 cm on one side of the floor, this is the length of standard sheets. If the plywood is tenoned, then the measurements must be taken very carefully, otherwise the tenons will not fit into the groove in one line. The use of tenon plywood eliminates the appearance of drafts, which is very important for high-quality installation of the finishing surface. For correct installation sheets, use coated thread.

Using a nail with thread (left) and coated thread (right) to mark

If the house is very large and the length of the thread is not enough, then you should first use a rope. Drive nails into the outer joists, taking into account the dimensions of the plywood, and stretch the rope between them. Taking into account the length of the coated rope, drive an additional one or more nails into the joists along the line of the stretched rope. Now the marks can be applied without fear, they will all be exactly on the same line.

Step 2. Lay out the first row of plywood on the joists, while first marking the excess width.

Important. The thickness of the plywood is selected taking into account the distance between the joists and the maximum load on the floor. This means that the sheets can be not only two centimeters thick.

Step 3. Apply liquid nails to the joists. They have several advantages: they significantly speed up the construction process, the subfloor will never creak, and they guarantee sufficient fixation strength. In addition, liquid nails allow you to easily correct small errors. The glue should be applied in the middle of the joist. If the edge of the sheet lies in the middle of the joist, then the glue, accordingly, is applied only to a narrow section of the element.

Step 4. Turn over the sheet of plywood and attach it with ordinary nails. According to existing rules the distance between them should be within ten centimeters around the perimeter of the building, and the length should be 6–7 cm. The distance between hardware along the joists is 15 cm, inside the building ≈30 cm.

Important. Plywood can expand due to increased humidity; leave a gap of a few millimeters between the sheets. It is convenient to use nails as a template; insert them between the sheets, and remove them after fixing. There are situations when the edges of the sheet do not fall in the middle of the joist. In these cases, the material must be carefully trimmed taking into account the requirements described above.

If the sheets fall on ventilation holes or other engineering communications, then measure their dimensions and exact location, then, using a manual electric circular saw, cut off the excess.

It is much easier and faster to hammer nails with a pneumatic hammer. How to quickly do this manually?

Put in left hand several nails, they are all mixed, the heads and points are located on different sides.
With your right hand, grab the nails by the heads, carefully pull them out, turn them over into the desired position and place them with the rest. Now all the caps are located on top.
Use your thumb to pry up the nails one at a time, grab them with your index and middle fingers and place them with the tip on a sheet of plywood. Do not forget that you need to drive the nails in at a slight angle to the plywood veneer, otherwise it may crack.
Hit the nail with the first light blow of the hammer, and with the second strong blow, drive it in until it stops.

You can be sure that after a few minutes of training, the speed of driving nails will not differ from that of a machine, and the quality will not suffer.

Step 5. Cut the last sheet to size and secure it to the joists.

The rows of joints should be staggered; for this, the next one must be started with half a sheet or the remaining segment. Joining tongue and groove plywood requires considerable effort. To do this, use a piece of wood, apply it to the edge and with strong blows use a hammer to connect the tenon and groove. Apply blows alternately on each side, do not allow the sheets to distort, remember the damper gaps.

Step 6. Mark the edges of the sheets protruding beyond the contour of the joists. It is better to use coated thread; carefully cut off the excess along the line.

Important. Be very careful when working with electric woodworking tools. Their injuries are complex and can cause disability. Tools must be in good working order and adjusted, and cutting devices must be sharp. Never remove factory guards.

Step 7 Proceed to seal the opposite edge of the floor. The work will go faster if you do not take the dimensions of each sheet, but attach whole ones. Then you should measure the width of the protruding pieces and transfer the lines to the front surface. Using an electric saw, cut off the excess according to the marks.

For the final covering of the subfloor, you can use most of the previously obtained sections, due to this the estimated cost will be reduced wooden house.

How to avoid mistakes during subfloor construction

The main advice is not to try to simplify existing technologies yourself. Only an amateur thinks that he is smarter than everyone else and can do the work faster and cheaper. All rules were developed taking into account long-term construction experience, each technological operation has its own specific purpose. An incorrectly laid subfloor causes sagging and squeaking.

Before starting work, check the position of the joists. The distance between the lags should not exceed 58 cm, this will allow the insulation to be tightly laid.
There is no need to skimp on the size of the beams. During the operation of the house, it becomes necessary to install heavy furniture; the likelihood of increased loads should be foreseen in advance.
In the place of masonry brick oven always reduce the distance between joists or beams. During construction, use only healthy lumber without natural diseases or defects.
Boards for making subfloors must have low relative humidity. If the subfloor is laid before the roof of the house is erected, then the work should only be done in good weather. Overmoistened boards not only quickly lose their original load-bearing characteristics, but also decrease in size during drying. As a result, the fastening is weakened, and the floor bends and creaks when walking. It is very difficult to fix the problems; often you have to completely dismantle the coating.
If the subfloor is located between the floors of a wooden house, then the cranial bars should be placed along the beams. Packed across, they reduce the height of the room.
When installing membrane vapor or waterproofing, carefully read the instructions. The material indicates which side it should face towards the insulation. The fact is that steam can only escape in one direction; if the fabric is laid incorrectly, then there will be no positive effect. As a result, the subfloor will be constantly wet, and the effectiveness of thermal insulation will noticeably deteriorate.
Do not skimp on the vapor barrier, cover the joists as well; attempts to cut the roll into small pieces always give a negative result. In terms of footage, the savings are negligible, and Negative consequences noticeable.
Always leave a ventilation gap between the rough and finished flooring. At the same time, consider the location of the air outlets.
All hidden wooden structures must be treated with antiseptics. We have already mentioned that the simplest, cheapest and safest antiseptic is ordinary oil or drying oil. The boards to be treated must be dry. If the antiseptic is quickly absorbed, the treatment should be repeated.
Practitioners recommend covering the ground under the floor of the first floor plastic film or roofing felt. Due to this, the amount of evaporated moisture is reduced, and the operating conditions of the building are significantly improved.
It is recommended to install a warm subfloor only under the living quarters of the first floor. There is nothing to save in unheated ones; an expensive complex cake is not needed.

Unconditional compliance with building standards guarantees that no unpleasant situations will arise during the operation of wooden houses. In all cases, eliminating the consequences of technology violations is much more expensive than complying with the rules for constructing subfloors.

Laying a subfloor is a fairly labor-intensive operation, but it is absolutely necessary. The structure of the lower floor of the house serves as its basis and is connected to the foundation. The subfloor serves as an intermediate link between the foundation and finishing while performing a number of specific functions.

1. Subfloor as a structural element of the house

After tying the foundation, the first step is to install the lower floor of the house. Further work on installing walls can be carried out on it. This is especially true for the construction frame house using frame-frame technology, and laying bricks and wall blocks from the inside requires a solid foundation underfoot. In addition to this, the lower ceiling performs a number of functions, being necessary element building.

Subfloor:

Distributes all loads on the lower floor, such as weight load-bearing walls and partitions, all people, furniture, household devices and appliances
Serves as a basis for work on assembling the frame and erecting walls
Is the basis for the finished floor
It is a component of the overall shell of the house, protecting it primarily from low temperatures

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

2. Types of floors

The main reason for installing different subfloor designs 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 different types of foundations can be laid for houses:

Slab
Tape
Columnar
Pile screw

The depth of the foundation and its piping may also vary slightly. However, there are some common features and design features of subfloors for all types of structures. In many cases, the base for the subfloor is lining beams, which receive and transmit all loads from the floor directly to the foundation.

In accordance with their functions, subfloors consist of several layers responsible for each of them:

The base of the floor is either soil or floor elements
The underlying layer is a layer of gravel, sand, slag, expanded clay, etc.
The base for the coating (screed) is a monolithic leveling layer
Layer of hydro- and thermal insulation
The floor covering itself

Subfloors are divided into three main types:

By lags
Along the beams
On the ground

The difference between the types of subfloors lies in the method of laying them, as can be seen from the name.

3. Preparation for installation of the subfloor

If the foundation of the house does not include a basement, then the base for laying the subfloor is the soil. It must be prepared accordingly for the construction of the subfloor.

Grass removal, various construction garbage and plant soil. Important point: You need to dry clay and loamy soils as best as possible, as they may contain a lot of moisture in the base. You should also not use soils mixed with snow and ice.

Then the site is carefully leveled. If necessary, soil can be added to the holes. After adding soil, it is distributed in an even layer and compacted with manual or mechanical tampers.

4. Laying the subfloor along the joists

Installing a floor using joists 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 beam or a thick board, sometimes placed on an edge.

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

If the room is significantly wide, the logs will be long, and it is not enough to lay them only on the external frame beam. In this case, additional supports are placed under the logs. There are several ways to install supports for joists.

The base is concreted and a thick board is laid on it, which serves as a lathing for installing the logs. This method is especially suitable for low bases above the ground. If the distance under the floor is large, 15-20 cm, and the floor is not concrete, posts are installed under the boards of the bottom sheathing, in increments of about 80 cm. The installation of posts can be done as follows:

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

Usually it is enough to lay the columns in two bricks in two layers, perpendicular to one another. You can make the columns entirely from concrete, but then you will need to build high formwork.

The height of all columns must be displayed in one plane. This is already controlled when 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 joists, 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 joists. For fine adjustments, thin sheets of plywood are usually used.

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

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

On top of the logs for installing a finished floor, you can fasten slabs of durable material - OSB or thick plywood. It is recommended to do this “staggered”, that is, the next layer of plywood or OSB is slightly shifted relative to the previous one.

If necessary, the cavities between the joists can be filled with insulation. This can be expanded clay or mineral wool, depending on the degree of required insulation of the house.

5. Floor with adjustable joists

Recently, a method of installing logs on adjustable stands has become popular. These are plastic screw supports, quite durable and lightweight. They are equipped with a stand square section, which is placed on a rigid base and with a screw, with adjustable height. Using them, you can quickly build a subfloor; moreover, it will not come into contact with the base, will be well ventilated, and therefore the need for waterproofing disappears.

The procedure for installing such logs is as follows:

Holes are drilled in the joist boards - in increments of 50-80cm
The log is installed in the right place
The support is attached to the base
The racks are twisted to the required level

6. Laying the subfloor on beams

The next way to lay a subfloor is to install it along beams. The main thing here structural element is wooden beam. It is made from timber rectangular section. To determine the cross-section of the beam, all load characteristics on the base of the first floor premises are taken into account. In order not to use a heavy thick beam that is physically difficult to work with, you can use double boards or boards mounted on the edge. Not a bad option there will be use of 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 pitch, m
Span length, 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 width is more than 6 meters, additional supports must be installed under the beams. These may be columns, 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 placed at its end into it. To isolate from external influences This hole is filled with tow. The depth of installation of beams in 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, cross beams for the subfloor are elements of the lower frame of the foundation.

7. Laying the floor on the ground

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

Let's consider this method in detail. It consists of several stages:

Leveling the base
Backfill with a layer of sand 10-15 cm at a humidity of 7-10%
Sand compaction
Add crushed stone and gravel 8-20 cm thick at a humidity of 5-7%
Laying an adobe-crushed stone or adobe-gravel layer about 10 cm thick
Compaction of this layer and the appearance of moisture on the surface
Pouring concrete mixture

As a result, after hardening, we will receive a flat, hard surface on which we can immediately lay the finished floor. Subfloor layers for better fastening and solidity, screeds are usually reinforced with reinforcing mesh. Thermal insulation of such a floor is conveniently carried out with polystyrene foam boards.

8. Installation of screeds

The top layer of the subfloor on the ground is called a screed. The 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 out the plane, so-called beacons are installed. These are, as a rule, slats with a thickness selected to create a plane. The mixture is applied to the floor and accelerated to the height of the slats.

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

Work on creating screeds must be carried out in the warm season, with an optimal air temperature of at least 15 degrees. It is recommended to apply a self-leveling layer on top of the main screed (its thickness is about 5-10mm) bulk method. For this purpose, there are a lot of different mixtures on sale.

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

9. Conclusion

The installation of subfloors is a rather labor-intensive process that requires compliance with all technologies, accuracy and known skill. In the simplest cases, you can do it yourself, but it is better to turn to professionals - the construction of the floor largely determines the structural strength of the building, the evenness of the surface and its suitability for finishing, as well as sufficient insulation and waterproofing of the entire house.

K-DOM specialists are ready to carry out flooring work, both rough and fine, in compliance with all requirements. The work can be performed either separately or as part of the construction of turnkey cottages.

The foundation has been poured, the walls have been raised, the roof has been installed and windows and doors have been installed. You can start laying floors in wooden house with your own hands. This stage of work is not difficult, but requires careful attention to detail.

Proper installation of the floor pie is the key to its long service life. A small mistake with waterproofing is enough and you will have to re-cover the entire coating in a few years. Lack of underground ventilation will lead to the same result. And without insulation, you will not only have to walk around the house in warm slippers, but also fork out for additional heating costs.

Subfloor - what is it?

It is important to protect a wooden house from moisture - rotting makes the elements of the building unusable very quickly. Therefore, you should not embed logs into the first crown of the log house, even if they are made of larch and treated with an antiseptic - in any case, they will have to be changed someday. It is optimal to lay the logs on the foundation and fix them after the walls have been raised.

It is also important to ensure good ventilation of the subfloor by arranging sufficiently sized vents in the base or foundation. According to the standards, in a subfloor without forced ventilation, the area of vents should correspond to 1:400 of the subfloor area. Otherwise, regardless of waterproofing measures, the picture under the house will be unflattering.

When the flooring is ready, you can begin insulation. But before laying the insulation, it is necessary to resolve the issue of protecting it from moisture - after all, wet mineral wool not only does not retain heat, but also contributes to the formation of fungus and mold on the adjacent wood.

Waterproofing and vapor barrier - what is the difference?

Waterproofing protects materials from direct ingress of water, and vapor barrier prevents the penetration of wet fumes. Thus, all waterproofing films are laid on the outside, and vapor barrier films on the inside. Everything is clear with the walls. But how and what to put on the floor?

Under hygroscopic insulation on the rough flooring of the first floor, it is better to lay any vapor-proof films, you can even use simple polyethylene films. They will protect expanded clay or basalt slabs from vapors rising directly from the damp earth. At the same time, expensive membranes that remove moisture outside are not useful here - all the evaporation still rises. But, given the ventilated subfloor, they are increasingly returning to time-tested glassine as a “breathable” material.

But on top of the insulation it is necessary to lay vapor-permeable films that remove possible moisture. To do this, leave a special ventilation gap (minimum 5 cm). If the joist boards are not high enough, a counter batten is nailed along them, on top of the membrane, on which the finished floor is laid.

Floor insulation - why is it necessary?

Even schoolchildren know the principle of convection - warm air rises up. By this logic, an uninsulated floor cannot release heat from the house. In fact, heat loss in a cold field reaches 20%!

All due to the same convection - air from the underground rises into the house, cooling it, and energy resources are also spent on heating the air in an unheated basement or underground.

Each type of insulation has its own advantages and disadvantages:

perlite, vermiculite, shungizite - analogues of expanded clay, do not absorb moisture, but are more expensive;

polystyrene foam and its derivatives are not susceptible to moisture, so they do not need waterproofing, they are lightweight and inexpensive, but they create a “greenhouse effect” in the house and are not recommended for wooden houses.

Bulk insulation is laid on a continuous flooring, slabs and mats can be placed on a sparse subfloor, you just need to properly lay the waterproofing and protect the insulation from rodents.

Finish floor and its types

Depending on the desired interior design, you can lay almost any floor in a wooden house:

Wood floors are great for living rooms. The main thing is to install good waterproofing to protect the insulation. But it is better to lay tiles in the kitchen and bathroom – places with high humidity.

In addition, there are variations with the device of warm wooden floors and even concrete screed by lags. So the choice depends only on construction skills and design preferences.

DIY technology for laying floors in a wooden house

Warm floors are comfortable, economical and extremely functional. Especially when you have to dry the winter overalls, jackets and mittens of three children after winter games outside. And so the entire floor area turns into a capacious battery - it would be a shame not to use it!

Concrete screed in a wooden house - reliability and functionality

In a wooden house, it is difficult to make a warm floor in a concrete screed, but it is quite possible:

The most important thing when pouring a concrete screed is to correctly calculate the load on the joists in advance. After all, the weight finished slab taking into account the finished floor it will be about 150 kg/sq.m and this does not take into account furniture and residents. When pouring concrete, the pitch of the beams is halved, and the logs themselves are lowered to the height of the screed (if the pouring is done only in the kitchen and bathroom, and not in the whole house).

A great way to reduce the weight of the floor is to not install a subfloor. Enough to secure at the bottom vapor barrier film slats so that the insulation boards do not sag.

Dense waterproofing is laid on top of the log with a mandatory ventilation gap of 5 cm. It is very important to glue all places where it is attached to the beams with butyl rubber tape - so that there are no holes left through which the screed will wet the insulation.

Slate or cement bonded particle board– they have the best adhesion to concrete. Formwork of the same height as the future screed is installed on top of the level. Reinforcing mesh is laid on the same slate substrate. The height of the substrate is about 1 cm.
A “snail” of heated floor pipes is laid out. It can be attached to the mesh with ordinary cable clamps. It is important not to forget to lay a damper tape between the formwork and the reinforcement to compensate for the expansion of the future floor.

To protect yourself, a test run of underfloor heating systems with increased pressure is carried out. If no leaks are found, you can start filling.

After pouring, it is better to vibrate the screed and only then level it long rule. Concrete needs to be watered for 1-2 weeks to gain strength. After a month, you can begin laying any floor covering.

Wooden floors - simple and beautiful

If the floor joists are not strong enough to support the weight of the concrete slab, no need to worry! After all, you can make a dry heated floor with water heating. To do this, you will need boards with grooves for pipes, and foil is used as a heat-reflecting layer. Laminate is laid on top. The entire process is presented in detail in the video:

The concept of “subfloor” hides not just poorly processed boards, but a real “pie” of various materials, which together form solid foundation for finished 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 a subfloor includes a set of measures that provide hydro, heat and sound insulation of the base. In this article we will look at how you can make a durable and reliable subfloor on which you can lay any finishing coating.

How to make a wooden subfloor on the ground

IN country house arranging the floor is a responsible and time-consuming task. Wooden flooring on the ground can be done without restrictions. Even if you live in a house temporarily, when the heating does not work, wooden floor serves for a long time without changes, since the underground is well ventilated through vents in the foundation.

For wooden elements For floor construction, it is necessary to select high-quality dried wood with a moisture content of no more than 12%. This is important, since wet wood can “lead” during operation. For the subfloor in the house choose conifers wood - spruce, pine, fir, larch. Wood saturated with resins is less susceptible to rotting and mold development.

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

The underground wooden floor on joists should be well ventilated. To do this, vents are made in the foundation, which are covered with a mesh with a mesh size of no more than 8 mm, so that mice do not get inside.

Wooden floor base

The design 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, logs can be laid on support beams, a crown molding or on support posts.

If the room is large enough, fixing the logs only at the ends to the beams will not be enough; the structure will turn out to be fragile. Therefore, in the spaces between the walls, support columns are installed on which the logs will be laid. The pitch between the columns depends on the cross-section of the lag. For example, if a 150x150 mm beam is used as a log, then the distance between the support posts should be no more than 80 cm.

How to make support pillars for joists:

First we make markings where the logs will be located. We make marks on the support beams or foundation of the house. Then we stretch the cords across the entire underground. We stretch the cords across the future logs at a distance of 80 cm or any other distance that is equal to the step between the posts. Support posts will be located at the intersections of cords or ropes.

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

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

After the concrete has completely dried, cover the surface of the column with roofing material or glass insulation in 2 - 3 layers. Definitely no sprinkles. Coat the surface and joints with mastic.

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

After the concrete has dried, the formwork can be removed. For greater reliability fertile soil It’s better to remove it 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 compact it thoroughly with a vibrating plate.

Before arranging the base, it is necessary to treat the beams, joists and subfloor boards with an antiseptic. The logs can be laid directly on the embedded crown or foundation and on the support columns, or you can first install the support beams on the columns, and then the logs across the top. Any option is correct. Only laying the logs across the beams provides a more stable and robust construction in the event that the distance between the logs is very small, 40 - 60 cm.

The cross-section of the logs must be selected taking into account the thickness of the heat-insulating material that will be laid 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. A ventilation gap of 30 mm must always be left.

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

Table 1. Lag step.

Let's consider laying lags on support posts:

We lay the logs on the embedded crown (support beams, foundation) and support posts. We control their even position, horizontal. A noise-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 post, springs well and conceals sounds.
If, however, sagging of the logs is noticed somewhere, it is necessary to place wooden blocks on the support posts under the logs and secure them firmly. If a beam sticks out somewhere, it can be cut off with a plane.

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

We fix the logs to support pillars using mounting brackets. On the wood side we secure it with self-tapping screws 50 mm long, and on the concrete column side we tighten the anchor.
The first to lay the so-called “beacon logs”, which are located at a distance of 2 m from each other. We will follow them further.
By analogy, we lay all the logs and check their even position.

After all the logs are secured, you can begin arranging heat and waterproofing.

Thermal insulation and waterproofing of wooden floors

Waterproofing and thermal insulation materials are laid between the joists. To secure them, it is necessary to arrange the base. There are several ways to do this.

Method 1. Sheets of moisture-resistant plywood can be nailed to the bottom of the joist. This design will be as reliable as possible. To do this, you will have to work underground, which is not always possible.

Method 2. At the bottom of the lag you can nail 20 mm thick cranial blocks, and roll the boards on top. This work is more painstaking, since you will have to cut a lot of boards with a cross-section of 15 mm and a length equal to the pitch between the logs.

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

We lay a layer of waterproofing with an overlap of 15 - 20 cm, and seal 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 in from the underground. Therefore, ordinary plastic film cannot be used.

We lay thermal insulation material on top of the film between the joists. We cut the rolled material with a width equal to the pitch between the lags plus 1 - 2 cm, so that the material fits into the gap between the lags at random.

Important! Can be used as insulation for wooden floors mineral wool in rolls, slabs, basalt wool, you can blow out ecowool, sawdust. Polystyrene foam and extruded polystyrene foam cannot be used. These materials are completely vapor-tight; a wooden floor simply cannot breathe.

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

Laying the subfloor

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

Subfloor from floorboards:

We start laying from the wall. We cut off the tenon and apply the board to the wall, leaving a gap of 2 cm.

Important! A distance from the walls is required, since wood is a plastic material; when it absorbs moisture, it expands, and when it dries, it shrinks. The gap will provide unhindered opportunity for the wood to expand and shrink.

We fix the board to the joists. From the wall side we screw the screws directly into the board, then this place will be hidden by the baseboard.
From the tenon side, we screw the screws into the tenon at an angle of 45 degrees.
We move the next board close to the first. We insert it into the groove of the first board.
We screw a self-tapping screw into the groove of the second board, securing it to the joist.
We lay all subsequent boards 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 laid offset - staggered.

The last board is secured so that the screw heads can be hidden under the baseboard. At this point the subfloor is ready. The main thing is to fit the boards tightly to each other. You can lay it on top flooring.

How to make a wood subfloor on a concrete base

In apartments with concrete floors, you can also make a wooden floor. The logs are laid on a concrete base, but for this it must be level. A height difference of several centimeters is unacceptable. Therefore, the option is to place wooden blocks, not suitable. Over time, the pads will dry out and become deformed, which can easily cause them to fly out and the floor will begin to creak.

Preparation of the base: hydro- and sound insulation

Before laying the joists on the concrete floor, it is necessary to level the base. 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.

We lay a waterproofing film on the surface of the concrete screed with an overlap of 15 - 20 cm, and seal the joints with tape.

We place soundproofing pads under the joists. To do this, you can use cork materials or foamed polyethylene with a thickness of 1 - 4 mm. Lining under the joists is needed to dampen impact noise.

Laying joists on concrete

It is advisable to use a beam equal to the length of the room. If this is not possible, then you can take a shorter beam and connect it to the end. The connection points should be spaced apart.

We lay the logs on the prepared base.
We check the horizontal position of the logs.
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 joists, we lay the insulation between the joists in the same way as in the case of a floor on the ground.

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

Installation of subfloor

We lay a subfloor on top of the joist. As mentioned above, it could be plywood, or it could be 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 joists and fasten them 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.
The joints of the plywood sheets must not be on the same line.

Do not forget that there should be a gap of 2 - 3 cm between the wall and the subfloor. The following floor coverings can be laid on top of the plywood base: 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 over the ground. There are certain restrictions. Firstly, groundwater on the site should be quite low - at a level of 4 - 5 m. Secondly, the soil must be stable, not mobile, otherwise the concrete floor may collapse. Thirdly, people must live in the house permanently, or it would be more correct to say that it must be heated during the cold season. If all conditions are met, you can safely fill concrete slab on the ground.

Excavation and foundation preparation

First of all, it is necessary to outline the “zero” mark - the level of the future floor. You need to orient yourself along the bottom of the doorway. All walls must be marked so that in the future you can see until when to pour concrete.

The floor on the ground is a multi-layer structure 30 - 35 cm thick. To equip it, we remove upper layer soil until the height from the zero mark to the bottom of the pit is 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, compact it, add sand to the required level and also compact it thoroughly.

We compact the base of the pit.
Pour a 10 cm layer of crushed stone and compact it thoroughly. If the thickness of the backfill is difficult to control, then we hammer several pegs into the ground at the required mark. After leveling and compacting, the pegs can be removed.

Pour the 10th layer of sand, water it and tamp it too.
Pour a small layer of crushed stone on top with a fraction of 40 - 50 mm.
Sprinkle with sand, forming thin layer, compact thoroughly.

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

At all stages of backfilling, it is necessary to ensure horizontality.

Waterproofing, thermal insulation, reinforcement

We lay a waterproofing material on the surface of the base - polyethylene film with a density of 200 microns, roofing felt or glass insulation. The main thing is that the material is not damaged by the edges of the crushed stone.
We apply waterproofing material to the walls to a level 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 durable thermal insulation material. For example, extruded polystyrene foam or basalt wool in slabs, perlite or expanded clay. You can also place the thermal insulation layer higher, on top of the concrete base.

Concrete floors must be reinforced. For this we use metal mesh with cells 10 cm.
We install the reinforcing mesh on stands 2 - 3 cm high so that the mesh is completely inside the concrete.

Installation of formwork and guides

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

We install formwork between the guides to fill the floor. This is not necessary, but it makes the task of pouring a concrete floor by hand much easier.

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

Rough floor screed - pouring concrete

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

We begin pouring concrete from the corner opposite the front door.
Fill several cards at once, then level them with a shovel.
We compact the concrete using an internal vibrator.
Level the surface using the rule. We set the rule on the guides and pull it towards us. Excess solution is distributed among cards that do not have enough solution.
We take out the cards and fill the voids with concrete.
When the entire floor is poured with concrete using this technology, it must be covered with plastic film and allowed to dry for a month.

For better drying of the concrete subfloor, its surface must be moistened with water.

After the concrete has completely dried, you can finish screeding the floor and laying the floor covering.

Making a subfloor 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 the old subfloor unless it has been completely renovated.