A lot depends on the quality of the floor subfloor. These include the service life of the finishing coating and the overall quality of the floor. Modern construction technologies allow you to create unique floors, but the traditional subfloor on joists is still popular. This technology has already been tested by time.

Everything you need to know about lags

Lags are called bars made of wood or polymer materials. They can have different sizes and different shapes. The logs are located under the subfloor covering. Among the advantages of this solution are:

• High heat and sound insulation properties;
• Uniform load distribution;
• Wide range of possibilities for leveling surfaces;
• A ventilated subfloor, in the cavity of which various communications can be located;
• Strength – the subfloor on joists can withstand static and dynamic loads of up to 5 tons per 1 sq/m;
• Ease of installation;
• Affordable price.

Logs can be installed directly on the ground, wooden or concrete floors buildings.

Classic flooring schemes

Floors can be either with or without underground space. Those structures where there is no underground floor are called cold, but there are technologies that allow such floors to be insulated.

Subfloors with crawl space come in more varieties. So, there are cold and heat-insulated ones. An insulated floor is equipped with a layer of heat-insulating material between the joists or between the supports.

Installation of a simple cold floor on the ground

This scheme provides that the logs will be mounted on a dry soil foundation. The first step is to remove all the fertile soil layer. Then the surface must be compacted with special care. Next, the surface is covered with sifted sand. If there is no sand, then you can use crushed stone or even construction waste, filled with sand.

The resulting pillow must also be compacted. To do this, it is recommended to use a vibrating plate, but you can also make hand tool from scrap materials. It is a fairly weighty deck, which is equipped with handles.

Then another layer of backfill is made. Here they already use calcined sand, slag, or dense clay. This layer will become the main one in the construction of subfloors. Already on this basis the logs will be installed. Therefore, such a base should not create conditions for wood rotting. As for the thickness of the pillow, it should be 3 times greater than the thickness of the selected block.

If slag, rather than sand, is used for the cushion, it should be delivered to the site about a year before the start of work on the construction of the base. This material needs to rest.

Mounted in the last layer wooden joists. The top line of the block should be flush with the plane of the base. Before installing wood in the ground, it is recommended to treat it with antiseptic materials.

The logs are laid at some distance from each other. This distance depends on the width of the boards with which the subfloor will subsequently be covered. So, for installing a subfloor in wooden buildings, where work is completed with flooring based on tongue and groove boards, the optimal distance is 60 cm.

Insulated floors

The design of an insulated subfloor on joists is slightly different from the design of a cold base.

So, the bottom of the pit, which resulted from the removal of the fertile layer of soil, is carefully compacted and then covered waterproofing material. Next, add a multi-layer pillow. First of all, crushed stone is poured. Its thickness should be no more than 8 cm. This layer is also compacted, and then filled with lime milk.

After this layer is covered with roofing felt, and then laid on top fiberboard sheets 30 mm thick. Then expanded clay with a small or medium fraction is poured. The layer should also be at least 8 cm.

The insulating base is filled with “lean” concrete, where the sand content is increased. After the solution has hardened, the area is additionally covered with sand, and then a scheme for arranging a conventional cold floor is used.

Installation of logs for different types of floors

If the floor is wooden, usually the beams are not perfectly even. The installation of a subfloor can be difficult, because when installing joists on such floors, it is not possible to obtain the most even horizontal surface. The joists should be strengthened on the sides of the beams.

The main advantage of this method is that there is no need for spacers that adjust the height. Fastening is carried out using partial screws, where the length of the screw is less than the length of the log. The diameter of the screw must be at least 6 mm.

When the beams are located too far from each other, a second syllable is laid perpendicular to the first syllable, but closer.

If the floors are concrete, then it should be taken into account that in this case it is necessary to take care of good waterproofing, otherwise the entire structure will be constantly damp. In this case, a different subfloor device is used.

When laying floors special attention is given to waterproofing, as well as heat and sound insulation. Also in mandatory A wet or dry screed is required. And only after all this the logs are laid and the finished floor is laid.

For logs, you should not choose short beams. If the length is not enough, then the parts are joined to each other end-to-end. The bars are laid directly on the screed.

Installation of logs on soft insulation is not recommended. In such a situation, the bars will “float”, which can lead to destruction of the finish coating. If heat and sound insulation materials allow, then the logs must be positioned so that the insulating materials are located between two bars.

Laying the joists correctly

Before starting work, the base must be thoroughly cleaned and treated with primers. Wooden parts dried and treated with an antiseptic. It could be bitumen. The soundproofing layer can be made of slag or sand.

Wood before and after treatment with an antiseptic.

It is better to install the logs from the window. The gap between the wall is made up to 40 cm. After the logs are laid, the plane must be checked against the rule. If you don’t see any gaps, it means everything was done efficiently.

Promising technology - adjustable logs

Gradually, new construction technologies reached these traditional floors. Thus, the installation of a subfloor using this method involves ready-made beams with threaded holes. They add reliability to the design.

In addition, such logs have an adjustment function. This can be done by rotating special bolts, which allows you to easily change the height of the bar at any time. When the adjustment is completed, the excess part of the bolt can simply be cut off.

Wooden floor with joists

Wood is one of the most the best materials for arranging subfloors. The floor, laid according to all requirements, has long term operation, does not require special care. Subfloor made of wood or plywood - an easy opportunity to level a crooked base, high thermal insulation characteristics, quick installation, efficiency and availability.

Plywood is best suited for constructing subfloors, OSB boards or chipboard sheets. Ideally, the slabs will have a tongue-and-groove end, and the thickness of the slab will be about 20 mm. It is also allowed that sheet materials will be laid in two layers.

Laying the sheets begins from the corner of the room. The first row should be positioned with the tongue against the wall. This leaves a gap between the board and the wall. It must be at least 10 mm. This is the so-called compensation gap. The next row is laid offset by two logs. If the boards do not fit tightly together, you need to adjust them by lightly tapping them with a hammer on the end of the board or sheet.

For fastening, lathing is used using transverse bars. The flooring is secured with self-tapping screws. The joints of sheet materials should be located on the central axis of the beam.

Finishing

When installing subfloors, it is important to get rid of small differences in height and various defects of boards or plywood. To do this, the surface is ground or scraped.

Then, the floors must be impregnated with oil, parquet varnish or covered with wax mastic.

That's all there is to say about subfloors. It's simple and affordable way, which will last for many years. You can watch the video to see how the subfloor is installed on joists. The video clearly shows all stages of work on different types foundations and ceilings.

When the initial stages of construction have come to an end and the walls have already been erected and the roof is in place, interior work begins.

At this point, they begin to arrange the floors. To do everything right, you need to provide protection to the finishing coating.

Wooden house

For this purpose, a subfloor is installed in wooden house. it is designed for insulation and additional protection main floor.

You don’t have to use a subfloor on the joists if this is a country house where the family lives only in the summer, or a summer kitchen. The question is whether flooring is needed wooden beams, a kind of rhetorical – master in in this case based on its requirements and capabilities.

Laying a subfloor in a room will save on heating costs, since the timber that is installed under the floor additionally retains heat. In addition, if you make a subfloor in a wooden house, you can count on natural ventilation, and protection from moisture that comes from the soil.

The subfloor will also improve sound insulation in the room.

Subfloor

Preliminary work

The main element of the structure is the logs. They are a beam or board up to 5 cm thick. In order for the floor to be of high quality and withstand loads, the boards and logs themselves must be securely fastened.

Attention! When laying, the logs must extend onto the base by at least 10 centimeters. In addition, a gap is left taking into account the fact that the timber expands with changes in temperature and humidity.

If the base is too narrow, the joists are cut into the wall. The arrangement can be done in another way: at a short distance, make a base of brick for support beams. The made column will become a support on the concrete base.

To ensure the flooring lasts a long time, it is important to use well-dried wood. The timber is also pre-treated with a special antiseptic. It is recommended to impregnate the material in two passes with an interval of several hours to protect it from rotting.

Laid joists

Preparing the base

The logs are mounted with their ends on the plinth, but before starting this action, a layer of waterproofing is laid on the concrete and the strapping is performed, for which it is used thin board. The ends of the logs must be firmly fixed with metal corners. In no case should the fastening be made rigid, since the ceiling must “breathe” and at the same time not change the structure after sudden changes in temperature and humidity.

Important! If in the future it is planned to install a fireplace, piano, or heavy furniture in the room, then the distance between the joists is reduced.

The gap that appears between the joists and the wall is filled using a special soft material for thermal insulation.

Subfloor in a wooden house

To install the subfloor, a low-quality board is used, since it is not visible. But at the same time, even lower grade boards are pre-treated by special means. For a high-quality result, it is not difficult to take a plane and trim the timber.

Beam for lag device

In addition to boards, chipboards or plywood are used to construct the subfloor. Roofing felt is used for waterproofing. If you make a subfloor with your own hands, it is recommended to start from the individual aspects of the room and material capabilities.

Installation of a high-quality subfloor in a wooden house

The lower part of the log is equipped with a beam, and the floor subsequently rests on this structure.

Typically, flooring is a board that is thoroughly dried beforehand. The boards are driven towards each other using a hammer, and no other fasteners are used for this.

Batten

Waterproofing is laid on the ceiling with a margin extending to the walls, which is subsequently cut off. Fastening occurs using metal brackets.

The next layer is a special membrane. It must be solid and end directly at the base of the wall. The joints are connected with tape. To ensure ventilation, a beam with a cross section of 5 × 5 centimeters is driven in.

In general, the question of how to make a subfloor has been sorted out, but the last stage remains - laying the finishing flooring. To make the floor beautiful and attractive, whatever top material you choose, secure it carefully with self-tapping screws. The main condition here is not beauty, but a macroscopic surface, so that the arrangement of the top layer is as simple and problem-free as possible.

What indicators to pay attention to when purchasing timber or beams

• The material must be processed before sale special composition, which prevents moisture;
• To prevent the floor from deteriorating prematurely, the timber is treated with a pest control compound;
• The board must be well dried. otherwise, during operation the material will be deformed;
• For the installation of a subfloor, it is recommended to give preference coniferous species, such timber will not rot over time due to the high level of resins.

Dry screed under the subfloor

If the house has concrete floors, they are leveled using a dry screed. This method is less expensive and takes less time than other options.

Dry screed with expanded clay

Attention! To make a dry screed yourself, prepare the tools in advance and purchase materials that are available to everyone today in construction stores.

Preparation

For something already ready concrete base lay a polyethylene film with an overlap of 15 cm. Scotch tape is used to secure the edges. After the completed manipulations, beacons are set. This is done using a water level, and the height is set wooden blocks, adding and removing which, we get the desired height.

Then expanded clay is poured in and, using a rule, it is carefully leveled along the installed beacons. There is no need to work with the entire floor at once; it is better to pour material with an area equal to a sheet of plywood.

Laying plywood sheets on expanded clay

After the first sheet is laid, beginners begin to doubt whether they did it correctly. Therefore, you need to stand on the plywood and walk around a little. Initially, the impression of a “sinking” floor will be created. But such doubt arises only among those who encounter dry screed for the first time. Do not be afraid, because after laying subsequent sheets it will become clear that the screed is effective and the sheets are in their places.

To attach the sheets, use self-tapping screws; they are fastened at a distance of 10 cm from each other. And for greater confidence in reliability, the joints are additionally treated with glue. It is better to apply the glue in “waves”, in a small layer.

At the final stage, the joints are treated with putty; after drying, the surface is sanded and leveled.

Installation of plywood sheets

Attention! If the screed of this type used for a bathroom or other room with high humidity, remember about additional treatment with a waterproofing compound. For these purposes, mastic or elastic solution is used.

And in conclusion...

Arranging a subfloor is not a difficult task, so you can do everything yourself. It is important to choose carefully from the beginning wood materials to cover and process them well. If the initial rough design is done correctly, then the floor itself will delight the owners for many years.

Ventilation holes (vents) must be provided in the base, which are subsequently covered with a special mesh. Air movement will prevent the wood from gaining moisture and protect it from mold and fungi.

Professional installation of a subfloor is shown in the video:

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Private low-rise construction in recent years is becoming more and more popular.

Country houses and country houses, built with their own hands, occupy an increasingly large share of the total volume of housing put into operation.

The most popular material in private construction is wood, due to its affordable cost and ease of processing. But not all individual developers have sufficient experience and knowledge to independently carry out the full range of construction work. So, the question often arises of how to properly lay the floor of the second floor in compliance with all construction standards and technologies.

Construction requirements for wooden floors

In order to install a durable and safe wooden floor between the 1st and 2nd floors with your own hands, you must strictly comply with the technical requirements for them.

Thermal insulation layer

Thermal insulation of the floor will improve the temperature in the room on the second floor

If a wooden floor separates the upper and lower rooms with a temperature difference between them of more than 10°C, it will be necessary to construct a thermal insulation layer.

This is necessary, for example, when arranging floors between the first floor and the subfloor, basement, or between the first/second floor and an uninsulated attic.

Beam strength

Beams and floors must withstand up to 180 kg/sq.m load

When constructing the floor of the second floor on wooden beams, special attention should be paid to the strength of the supporting structures. The safety of the building depends on how strong the wooden floor beams are.

According to building standards for wooden low-rise buildings, the maximum load on the floors of the first floor should not exceed 210 kg per sq.m., the pressure on the wooden floor of the second floor should not exceed 180 kg/sq.m., and for attics and attics this figure should be less than 105 kg/sq.m.

Maximum deflection

In addition, building regulations also impose requirements on the deflection values ​​of wooden floor beams. According to SNiP, this coefficient should not exceed 1 to 250. That is, the maximum deflection of wooden load-bearing structures during operation should be less than 4 mm per meter of beam length.

According to this standard, the deflection of a beam structure 4 m long in the center should not be more than 1.6 cm (4 m: 250 = 0.016 m). If you plan to place massive furniture in the room and household appliances, flooring as flooring tiles etc., then the requirements for structural rigidity increase to 1 to 400.

That is, the deflection should not exceed 2.5 mm per meter. For non-residential attics and attics, a higher deflection coefficient is allowed - 1 to 200 (5 mm per 1 meter).

Soundproofing

Fifty-millimeter mineral wool will not only insulate the floor, but will also become a good sound insulator

According to building regulations, the sound insulation threshold for interfloor ceilings residential buildings should be 50 dB.

To meet this requirement, it will be quite enough to cover the floor of the second floor under finishing coat mineral wool 50 mm thick.

The length of the beam should be no more than 5 m

The maximum permissible length of free sag of wooden beams should not exceed 5 m for interfloor and 6 m for attic floors. If the design length of the room is more than 5 m, it will be necessary to install additional support under the load-bearing beam. The fact is that the optimal length of a load-bearing wooden structure is 4 m.

With a further increase in its length, the rigidity and strength of the supporting structure sharply decreases and the requirements for the thickness of the beam section increase disproportionately. So, in order for the deflection indicators for an 8 m beam to “fit” into SNiP standards, its thickness should be about 40 cm. For example: the same deflection indicator is shown by a 4 m beam with a cross section of only 15 x 15 cm.

Wood is a material quite vulnerable to external influences, primarily dampness and fire, therefore, before proceeding with the construction of load-bearing structures, all wooden elements must be treated with antiseptic materials and fire retardants.

Construction material

Before you begin installing the floor on the second floor using wooden beams, you should make a list of all the necessary materials. This will allow you to avoid unexpected downtime and delays during work caused by the need to purchase additional building materials.

Beams

A beam section of 15 x 15 will be sufficient

The basis of the entire structure of interfloor wooden floors is beams. They act as load-bearing elements, and the strength of the structure depends on them. For them, a beam or carriage with a section of 15 x 15 cm or 18 x 18 cm is usually taken.

This cross-section is usually enough to provide sufficient rigidity for a specific load of 400 kg per sq.m. In this case, it is necessary to comply with the parameters recommended by construction standards: the span length is 4 m, and the step between the beams is 60 cm. Based on these parameters, you can also calculate the required amount of timber.

№	Span length (mm)	Beam cross section (mm)
1	2000	75×150
2	2500	100×150
3	3000	100×175
4	3500	125×175
5	4000	125×200
6	4500	150×200
7	5000	150×225

However, in the absence of timber and small values ​​of the expected loads on the floor, it is quite possible to use boards 50 or 40 mm thick, knocked together in pairs and placed on edge. This option is suitable for installing floors in an attic or in a small country house.

For the first floor of a residential building, this option is not suitable due to the low load-bearing capacity of the boards: to ensure the necessary rigidity, the pitch between the board beams will have to be significantly reduced, which will lead to an unjustified waste of material.

Pine is most often used as a material for beams. This best option according to the “price-quality” criterion: its wood is quite affordable and at the same time has good technical characteristics.

Beams made from wood of stronger species (larch, oak) can rarely be found on the open market, and their price is incomparably higher, and pine wood, after appropriate treatment with antiseptics, will be little inferior in durability to the same larch.

When purchasing timber, you should choose a material with dry wood. Otherwise, after installation of the beams, they may become deformed during the drying process - bending and twisting.

Flooring

Wood flooring, laid on beams will be a rough base for the floor covering

Typically, the flooring of interfloor floors is two-tiered: below are subfloors, on which insulation is laid, and on top is a pre-finish flooring mounted on top of the load-bearing beams. Decorative flooring is laid directly on it.

To determine the nature and quantity of flooring material, you should clearly think through the design of the floors.

When constructing a subfloor, either 5 x 6 cm bars, packed onto load-bearing beams, or grooves made in the beams can be used as support for the flooring boards. The latter option is quite labor-intensive, so most often 5 x 6 cm bars are used to create support.

To calculate the required number of bars, it is enough to count the number of beams and multiply them by the length of each of them. Received footage ( total length all beams) multiply by two more (since the bars will be packed on both sides of each beam).

A wide range of materials can be used for finishing flooring. This can be plank flooring, plywood, chipboard panels, MDF, OSB, etc. Each of these materials has its own advantages and disadvantages, after reading which you can choose one of them. To calculate required quantity material, it is enough to simply calculate the area of ​​​​the room.

When purchasing building material, you should always purchase it with a reserve of 10–15%, since during construction unforeseen material overruns are inevitable.

This will save you from having to interrupt your work and buy the missing part.

Impregnations

Antiseptic will extend the life of wood

To maximize the service life of wooden structures, they must be treated with antiseptic materials.

It would also be useful to treat the wood with fire retardants, which increase its fire safety.

To calculate the required amount of impregnation, you should read the instructions for its use - the approximate consumption of the mixture per sq.m. is always indicated there.

Waterproofing

Since wood is afraid of moisture, waterproofing materials are always used during construction.

It could be roll waterproofing, used to create a water-repellent layer between wooden floor structures and the finishing coating, or between wood and brick (stone, cinder block, etc.).

To protect wood from dampness, you can also use coating waterproofing based on polymers or liquid bitumen.

Heat and sound insulation

If it is necessary to create a barrier to noise or cold, insulating materials are used in the construction of floors. Most often, mini-slabs or polystyrene foam are used for these purposes. Their total number in area should be approximately equal to the area of ​​the room. For more information about floor insulation, watch this video:

Expanded clay or ordinary slag mixed with sawdust can also be used as an insulating material.

Fastening materials

For fastening wooden elements floors, you should purchase screws, nails, steel corners, anchor bolts and other consumables. When purchasing screws and nails, you should pay attention to their length.

According to the standards, for a strong connection, the nail must be 2/3 longer than the thickness of the element being attached (board, block). For self-tapping screws and self-tapping screws, this figure can be reduced to 50%.

Those. For reliable fastening for the beam of the “magpie” board you will need 120 mm nails or 80 mm long self-tapping screws.

After all the necessary materials have been purchased and all preparations have been completed, you can proceed directly to construction work. The construction of interfloor slabs can be divided into several main stages.

The part of the beam inserted into the wall is wrapped in three layers of waterproofing material

The installation of load-bearing beams is most often carried out during the construction of the walls of the building. Before laying the load-bearing beams, their surface is treated with all necessary impregnations.

Then their ends are cut at an angle of 60° and the part that will be walled up in the wall is wrapped in 2-3 layers of rolled waterproofing.

The ends of the beams are usually also coated with waterproofing compounds, but some experts advise leaving them open to allow the moisture contained in the wood to freely escape.

The depth of the beams inserted deep into the wall should be at least 15 cm. The laying step of the beams is usually taken at 0.6 m, but depending on the expected load on the floors, as well as on the thickness of the beam section, this figure can be reduced or increased.

The choice of interval between beams is also influenced by the technical characteristics of the material used for the finished floor.

If the top flooring is supposed to be made of inch boards, plywood or chipboard, then the distance between the beams should not exceed half a meter, otherwise the floors will sag when walking. For more information about installing beams, watch this video:

Floor joists must lie in the same plane

The installation of load-bearing beams begins from the two outer walls, while the beams should be located at a distance of 5 - 10 cm. After installing the two outer beams, we install the rest, observing the required interval.

When laying beams, special attention should be paid to the horizontal slope: all floor beams must lie in the same plane. To do this, place an edged board between the two outer beams, or pull the twine tightly.

If the base on which the beams are laid is uneven, then for leveling horizontal level Mortgages should be installed under the ends of the beams. For mortgages, a material is used that is resistant to rotting and physical stress - metal plates, pieces of tile, etc.

It is not recommended to use wooden wedges to adjust the level of beams, as they can rot quite quickly, which will cause individual floor beams to lower and bend the floor line.

The supporting beams are attached to the wall using anchor bolts and steel corners.

Fastening the support bars

After all the floor beams have been exposed, bars with a cross section of 5 x 6 cm (the so-called “cranial” bars) are attached to them. They serve as a support for laying the subfloor and are attached along the entire length of the supporting beam, on both sides.

They should be nailed in such a way that they bottom part was flush with bottom beams

Most often, the subfloor is made from inch boards

To construct a subfloor, edged boards are taken and laid across the beams on support bars. Since the distance between the beams usually does not exceed 0.6 - 0.8 m, then an inch or thirty board is quite suitable for subfloors: the pressure on them will be limited only by the weight of the insulation.

You can also use a trimmed slab for these purposes. You can also combine the subfloors of the second floor with the finished ceilings of the first floor or basement. In this case, the edged boards are hemmed from below, from the side of the first floor to the beams. For more information about the draft field, watch this video:

Thermal insulation flooring

After installing the subfloors, compartments are formed between the beams, which can be filled if necessary thermal insulation materials.

To do this, a hydro- or vapor barrier (roofing felt, isospan, etc.) is laid on top of the subfloor boards, and then mineral wool, polystyrene foam, slag with sawdust, etc. are laid.

In this case, the entire space between the bars must be densely filled. We fill the gaps between the beams and the foam sheets with sealant.

It is also advisable to lay waterproofing on top of the insulation, which will protect it from moisture leaks from above.

The final stage will be laying the finished floors, which are attached on top of the load-bearing beams using self-tapping screws or nails.

To do this, the material (boards, OSB, plywood) is cut so that their joint falls in the middle of the beam. The finished floor is the basis for the finishing coating - laminate, linoleum, parquet.

One of the stages of building a house is installing floors. How to properly lay a subfloor on wooden beams so that after a few years you don’t have to redo the finished floor structure? What should you pay attention to when designing and what are the most common mistakes that novice builders make when creating subfloors on wooden joists?

This technology is often used by builders when constructing warm buildings. The main task of the subfloor is to create a solid base for a decorative coating that does not have the necessary strength. Such coverings include linoleum, carpet, laminate, etc. Also, the task of the subfloor is to maintain a level surface for subsequent installation parquet board or PVC tiles.

Regardless of the type of foundation chosen, if the owner wishes, a subfloor can be made using wooden beams. The type of foundation directly depends on the terrain, proximity groundwater, as well as the weight of the future structure. The most popular types among developers are:

• Recessed tape. One of the most expensive types that is used to create basements or ground floor. Floor slabs, made at the factory or cast at the construction site, are installed on the finished strip.
• Shallowly recessed strip foundation(MZLF). In this case, the logs rest either on a rough screed or on beams that lie on the foundation strip.
• Columnar foundation. The logs are fixed in lower crowns log house or rest on the lower frame made of boards or timber. Additional support points are provided on pedestals or pillars made of ceramic bricks, cinder blocks or other durable materials.

Subfloor on brick cabinets

What is a subfloor over wood beams? Many experts mistakenly consider the subfloor to be the flooring that is nailed from the bottom to the skull beam. But it is not a mandatory structural element and serves as a support for laying thermal insulation materials. Essentially, it is a support layer. A true subfloor is a flooring laid on top of beams or joists. It gives the necessary rigidity to the base for subsequent laying of the finishing coating.

Calculation of wooden floor structure

How to correctly calculate the cross-section of a beam used in the construction of a future house? Otherwise, there is a high risk of floor sagging, laminate creaking and other equally unpleasant nuances. Experienced builders They recommend either leaving the arrangement calculations to professionals, or trying to figure out this system yourself.

So, the main load-bearing element when laying a subfloor on wooden beams is the beam itself. It bears the main load, therefore the correctly selected section and pitch of this structural element is the key to long-term operation of the future floor. The dimensions of the beam range in height from 10 to 30 cm, and in width from 7 to 20 cm. Optimal width The pitch (distance between adjacent elements) of the beam varies from 60 to 100 cm.

The calculation of the beam section is determined based on several factors:

• Span lengths;
• Features of the operation of the premises;
• Maximum load per m 2 of floor;
• Etc.

If timber of the required cross-section is not available, it can be replaced with boards placed on edge and fastened together to achieve optimal thickness and heights.

Table for calculating floor configuration

Determining the cross section of a beam is carried out using simple calculations. There are specialized tables that indicate the main parameters of a wooden beam under certain factors. Thus, it is necessary to take into account the loads that consist of the weight of the floor, as well as the mass of people and potentially furnishings placed on it. The average load is about 400 kg per m 2. If we consider the arrangement of floors in non-residential premises, change houses, garages, bathhouses, etc., then the average load on square meter surface is 300kg.

Next, we find the span length in the table. In our case, let’s say it is 4m. And we select the installation pitch (distance between the beams) equal to, for example, 65cm. In this case, the ideal beam cross-section is 10*20cm. It is important to remember that if the span length is 4 m, then the length of the beam must be chosen 30 cm longer. That is, 15 cm on each side for secure mounting in the wall. The more efficiently and meticulously the calculation of the load-bearing elements is carried out, the more reliable the finished structure will be. Optimal size beams and step widths allow you to evenly distribute the load on the floor coverings and ensure a long period of flawless operation of the structure.

Methods for attaching beams

The success of creating a reliable subfloor largely depends on how carefully the installation of the beams is carried out. The method of fastening wooden beams has its own differences when installing from brickwork, in a panel structure, as well as in a log structure.

Brick house

Installation of wooden beams in this case will require the organization of nests for their fastening. They become the supporting elements that hold the beams at a certain level and in a strictly specified position. Experts attach great importance to the scrupulous alignment of nests to a single level. After completing the stage of creating them, you should use cement mortar give them a perfect bottom flat surface. Complete drying of the solution serves as a signal to place a layer of roofing material or roofing felt inside the nest. This is done to protect the beam wood as reliably as possible from negative influence moisture. It should be remembered that the size of the nest must be 6-10 cm larger than the cross-section of the beam. the distance between the beam and the wall varies within 3cm. And the depth of the nest is 20-25cm, provided that the beam enters it only 15cm. The part of the beam that will be placed in the nest can be processed using hot bitumen solution.

Wooden houses

Subfloor in a wooden house

For buildings made according to frame technology or made from timber or logs, the gaps between the beam and the wall of the nest are slightly smaller and amount to 1 cm. The ends of the beam are not treated with bitumen solution, but are only tightly wrapped in tow and placed inside the nest. Otherwise, there are no significant differences between the technology for preparing nests and the subsequent fastening of a wooden beam in a brick or panel house does not exist.

Installation of a classic subfloor

After installing the beams in the sockets, it is necessary to secure the cranial bars on their narrow sides. The fixation is carried out in such a way that the cross section forms the letter T. The classic section of the bar is 4*4 or 5*5 cm. At the time of fastening, it is necessary to ensure that the surface of the bars is perfectly flat. This will avoid difficulties when installing slab flooring material.

Classic subfloor

There are certain rules laying the subfloor on wooden joists, which are prescribed in the construction regulations. OSB boards, plywood, chipboard, as well as tongue and groove boards or edged boards can be used as flooring materials.

There are certain rules for laying slab material and edged boards on wooden logs to give maximum strength to the finished structure:

• The top layer of plywood veneer must be fixed in such a position that it is located across the joists.
• Long side chipboard sheet located along the run. And the installation of parallel joints of adjacent sheets should be carried out staggered.
• When laying plywood sheets, it is possible to shift joints perpendicular to the direction of the beams.
• When using edged or tongue-and-groove boards, you must choose a size that is at least 18cm wide. The purlins provide precise support, and the angle of attachment of the board to the purlin should not exceed 45 0 C.

This is important: fastening the flooring as a base for subsequent finishing coating should be done using self-tapping screws. Only when subsequent installation of a flexible base is planned is it necessary to use nails equipped with a ruff notch or ribs.

It should be noted that the service life of the future floor directly depends on the quality of the flooring. The installation of thermal insulation materials also plays an important role. You can choose as insulation various options materials.

Laying thermal insulation

To ensure that the finished base structure is not only strong and durable, but also warm, experts recommend using thermal insulation materials, as well as vapor barrier membranes. The main layers of the so-called “pie”:

• Waterproofing layer. Its task is to prevent the wood from becoming saturated with moisture. For this purpose. A diffusion membrane is used, located under the beams.
• Layer mineral wool or other slab insulation. It is mounted directly on the diffusion membrane.
• The vapor barrier is located directly under the subfloor material. Experts prefer foil materials that can reflect heat back towards the room. This allows you to reduce the cost of heating the building.
• Sound insulation is used mainly in the construction of houses with 2 or more floors.

A prerequisite is the use of antiseptics for treating the base slab material, as well as joists and cranial beams. Their use is most effective before the stage of cutting slab material or wood. The cut site must also be carefully processed. In this way, it is possible to increase the service life of the finished subfloor on wooden joists.

Floating subfloor method

Distinctive feature this method the creation of a subfloor was the absence of load-bearing structures that are built into the walls (beams). That is, it does not have an attachment to load-bearing walls. This technique has become widespread in the construction of houses on strip foundations.

Steps to create a floating floor:

• Removing soil from the underground;
• The resulting space must be filled with crushed stone, which will act as insulation;
• Compacting gravel bed;
• Installation of brick pillars around the perimeter of the room. Their minimum dimensions are 40*40cm;
• Laying a layer of roofing felt on the surface brick column for the purpose of waterproofing;
• Fastening beams treated with antiseptics. The optimal step between them is 65-70cm;
• Fixing slab material used as a subfloor.

Subject to availability cement screed For indoor flooring, a method called a dry floating floor can be used. For this purpose. It is necessary to put marks on the walls that characterize the horizon level. Then fine expanded clay is applied to the floor. It should be carefully leveled and compacted. The top part of the subfloor floating floor is a gypsum fiber board. Its installation is carried out in the direction from the door to the window. The final stage is the installation of decorative covering in the form of laminate, linoleum or carpet.

Layers of floating subfloor

The undeniable advantage of a floating subfloor is the minimal load of the floors on the foundation. It also has excellent soundproofing and thermal insulation properties. This option for installing a subfloor is economical, simple and reliable.

Making a subfloor with your own hands is not difficult. You will need a tool quality materials, as well as the desire to make your home warm and comfortable!

When installing a floor in a wooden house, it is important to take into account some of the design features. You also need to take into account all the elements that will be required to complete the installation. The subfloor in a wooden house is made with your own hands, you just need to do some research. At the same time, you will not have to spend money on attracting professional workers.

Features of the floor in a wooden house

The floor arrangement must take into account the type of floor. Reinforced concrete is not used in a wooden house, since they have a very large mass and transfer increased load to the walls. The ceiling is arranged on beams. Most often they are wooden, but sometimes it is more rational to use metal ones. Floor installation must take into account the limited load-bearing capacity of the floors. There are two options:

• floors on joists;
• rough screed.

Each of these methods has its own characteristics and scope. When installing floors in living rooms, most likely the finishing coating will be linoleum, laminate, parquet or carpet. They are quite light and wooden structures They can handle that weight without any problems. In this case, it would be better to make a subfloor in a wooden house along the joists, and use wooden ones as load-bearing floor beams.

Installation of floors in the bathroom, toilets, kitchens, and corridors involves the use of more wear-resistant materials. In most cases, the choice is made on ceramic tiles. It is resistant to mechanical stress and moisture. For wooden house can be cited following tips:

1. It is better to install floors with your own hands in wet rooms using tiles. But you need to take into account its weight. The most optimal solution The situation will lead to the following solution: make a ceiling in the bathroom and toilet using metal beams, on which to lay a corrugated sheet. Concrete is poured over the profiled sheet and reinforcement is laid. A cement-sand screed is provided on top of such an overlap, on which ceramic tiles are mounted. This method is applicable only for individual rooms of a wooden house, since it creates a large load on the walls made of timber or logs.
2. It is better to avoid installing ceramics in the corridor in favor of lighter laminate or linoleum. This will avoid overloading wooden floors and walls. Tile screed can also be poured onto a wooden floor, but this is an extremely undesirable measure, which reduces the reliability and safety of the house.

Once you have chosen to install the subfloor and ceiling yourself, you can begin to study the technology.

Floor installation using joists

In essence, logs are load-bearing floor beams, which is a system of main and secondary load-bearing structures or involves the presence of only one row of beams. Do-it-yourself installation is performed in the following order:

1. Procurement of material. It is necessary to purchase the required amount of wood and prepare all the elements. To do this, you will need to develop a drawing of the future floor along with a floor plan, which indicates the sections of the elements and their lengths.
2. Wood processing. Here you will need two compositions. The first will protect the tree from damage by mold, mildew and other harmful microorganisms - an antiseptic. The second will help increase the fire resistance of structures - fire retardant. In private construction, no one will check for the necessary treatments, but it’s worth doing them for your own peace of mind. If the wood is not treated, it will begin to rot in a short time, which means that the structures will have to be repaired or replaced.
3. Next, the installation of the floor and ceiling involves the installation of the main beams. Their cross-section depends on the span, which for a tree should not be more than 7-8 meters. On average, the cross-section of beams is 100 by 200 mm. The step can be chosen differently, but it is better to take it approximately 1 meter. The beams rest on the crowns of the walls, in which notches are specially provided for this purpose. To prevent floors from creaking in the future when doing work with your own hands, it is necessary to provide a gap between the end of the beam and the wall of approximately 3-5 mm.
4. The next step is the installation of the cranial bars. They are needed to lay the sheathing that will hold the insulation. For a private house, you can take bars with a section of 50 by 50 mm. They are attached on both sides of the load-bearing beams. Skull bars located below. Fastening is carried out with self-tapping screws.
5. Boards are supported on the bars, which must be laid perpendicular to the direction of the supporting beams. Fastening is done with self-tapping screws. The cross-section of the boards depends on the distance between the main beams. In most cases, a thickness of 32 mm will be sufficient. These boards will also become the ceiling of the lower floor along which the sheathing will need to be made. It is highly not recommended to walk on such flooring. It is not able to withstand a large load, and is designed only for the weight of the insulation and the ceiling.
6. Next, the device involves installing insulation. It is laid on the flooring installed at the previous stage between load-bearing beams. The thickness depends on the location of the overlap. If it is located between floors, then a small thickness is sufficient to ensure sound insulation (30-50 mm). If the overlap separates cold basement or an attic from a residential floor, then 100-150 mm of effective thermal insulation will be required.
7. The next stage is the installation of flooring. It can be attached directly to the main beams, perpendicular to them. Additional items are needed if the step of the main ones is too large. In this case, they are located transversely, and the flooring boards in this case will be parallel to the main load-bearing elements. Additional beams can be attached either on top of the main beams or on the side of them. For flooring, it is recommended to take a board of sufficient thickness. It all depends on the load, but optimal value thickness is 50 mm. The fastening is done with your own hands using self-tapping screws.
8. After this, you can begin laying the finished floor.

Laying parquet on a subfloor

Filling the screed

To lay tiles on the floor, you will need to make a screed.

After the installation of floors on wooden beams has been completed, you can begin to create a screed for the finished floor from ceramic tiles. There are three manufacturing methods:

• cement-sand screed;
• self-leveling (self-leveling) mixtures;
• dry screed.

In all cases, before starting work, you will need to level and clean the floor. After this, a plastic film is laid on it, which will serve as waterproofing. Further the process is different for different methods. With self-leveling mixtures, the order is approximately the same (it is important to read the instructions on the packaging).

If you decide to make a dry screed, you will need expanded clay. This option is attractively priced and does not require drying time. The minimum bedding layer is 20 mm. The screed is made using pre-fixed beacons. Sheets of plywood are laid on the expanded clay and secured with self-tapping screws. After this, a finishing floor is made.

Expanded clay is not resistant to water, so when performing work in wet rooms, it is better to cover it with bitumen mastic or a high-mobility cement-based mortar.