What bars to use for lag. Lag size for the floor - recommendations for arranging a wooden floor

Wooden flooring on logs is one of the oldest flooring methods and the only one used in the northern regions of our country. Modern materials only improved old technology, due to which the scope of application has significantly expanded and performance indicators have improved. Before proceeding directly to consideration different options, you should familiarize yourself a little with the engineering requirements for calculations.

Lags are distinguished from beams by their smaller size and mobility. If the beams cannot be moved after installation, the repair is very long and labor-intensive, then the beams are a mobile architectural element. They are much easier to install, and if necessary, repairs are made faster.

Before proceeding with the construction of the floor, you need to study the requirements normative documents to the dimensions of the lag and the distance between them, taking into account the thickness of the floorboards.

Lag section table at a step of 70 cm

Table of the distance between the lags, depending on the thickness of the board

In order to learn how to independently make calculations based on tables, it will be useful to consider simplest example... Initial data: the length of the room is 10 m, we take floorboard 30 mm thick.

Calculation method

According to the table, with such a thickness of the board, the distance between the lags is 50 cm, with a room length of 10 m, 20 lags will be needed. The removal of the lag from the walls cannot exceed 30 cm. This means that we will have to increase their number by one piece, the distance between the rest will decrease to 45 centimeters.

Important note. During calculations, all rounding should be done only downward, thus creating an additional margin of safety.

There is no need to calculate dimensions and distances with millimeter precision, no one does such measurements. By the way, during construction, the absolute majority architectural elements and structures are measured in centimeters, the greatest accuracy is half a centimeter. Millimeters are almost never used during measurements.

Floor base options

These types of floors can be placed on wood and concrete base or on the ground. Each option has its own technological features which must be borne in mind during the production of work. As for the specific purpose of the premises, taking into account this parameter, the base of the floor and its performance characteristics... The technology of the device itself remains almost unchanged. There are, of course, options for warm and cold floors, but these features have a general construction algorithm.

Installation of a wooden floor on logs on wooden bases

Such floors can be made both in wood and in brick buildings, can have several varieties. It is necessary to think over the features of flooring at the stage of building design. Not only the purpose of each room and its size are taken into account, but also the climatic zone of residence, the requirements for the microclimate and the financial capabilities of the developer. Given below are step by step recommendations construction of this type of flooring.

Depending on the specific conditions, the algorithm can be slightly changed, but all the main construction operations are mandatory. The base can be moisture-resistant OSB boards or plywood sheets. The design of the flooring provides for the possibility of laying insulation, it is allowed to use rolled and pressed glass wool or foam. If there is insulation, then it is imperative to put a hydro and vapor barrier.

Step 1. Take off the dimensions of the room and calculate the number of lags, taking into account the above recommendations. Prepare materials and tools, make markings. Do the work slowly, mistakes made at this stage have extremely negative consequences. Removing them will take a lot of time.

Step 2... Begin to install the logs from the extreme wall ones. If the room has black floors, then the logs can be fixed directly to them. To facilitate the work, it is better to use metal squares with perforation, such elements significantly speed up work and increase the stability of the log. Along the mark on the wall, taking into account the thickness of the floorboards, set one end of the log, fix its position.

Practical advice. During the installation of the extreme lags, do not fix them immediately, at first the screws should only be baited. This will enable the final fine adjustments to be made.

Do the same at the second end of the log, constantly monitor its position in level. The lag code lay down normally, you can fix the ends firmly and proceed with the installation of intermediate fasteners. The distance between them depends on the thickness of the boards that are used for joists, it is about 70 centimeters.

Step 3. Between the extreme lags, you need to pull the ropes, set all the remaining lags along this line. Constantly check with a level, the accuracy of installation should be ± 1–2 mm. It doesn't make sense anymore, it takes a lot of extra time. A slight difference in height will be removed during the finishing of the front surface of the floorboards.

Step 4. If the floors are warm, then it is necessary to lay thermal insulation between the logs; to prevent moisture ingress, waterproofing and vapor barrier are used. The distances between the lags need to be adjusted taking into account the length and width of the insulation. It could be like mineral wool or polystyrene, and bulk types of insulation. If all preparatory work are completed, you can start laying the floorboards.

There are options for mounting logs on floor beams. These are the so-called ventilated floors, which are most often used for non-residential premises. It is not necessary to observe special accuracy, the alignment of the sizes is done with lags. Lags are fastened to the beams with nails or self-tapping screws from the side. The work algorithm is the same. First, the extreme ones are put, a rope is pulled between them and all the rest are fixed along it.

Ventilation is carried out through special vents in the foundations, the distance between the ground and the floor must be at least fifty centimeters. Otherwise, the frequency of air exchange does not meet the required indicators, and this becomes the cause of damage to wooden structures.

Floor installation on wooden logs for concrete

Such floors are considered more complex, time consuming and expensive; all wooden structures must be reliably protected from direct contact with concrete. Otherwise, the structures will quickly become unusable and will have to be changed prematurely. There is chemical method lag protection from decay processes using various impregnations. They are quite effective, they really prevent the process of wood spoilage. But unfortunately soaked wooden structures can no longer be considered environmentally friendly, and it is for the sake of this indicator that most developers install natural wooden floors.

If the logs are laid over the entire area on concrete, then waterproofing is required between them.

But you can also fix them with metal squares, which allows you to make a gap between the base and the log. It should be borne in mind that in this case the load-bearing characteristics of the floor are somewhat reduced.

This fixing method has its advantages. Firstly, direct contact of wooden structures with concrete is completely excluded. Secondly, the logs are allowed to be installed on a black screed. With the help of corners, you can eliminate irregularities of a few centimeters, there is no need to do finishing screed... This saves a lot of time and money.

The second way of laying on concrete screed- the logs are placed directly on it; a material based on modified bitumen is used for insulation.

Laying logs on the ground

The method is used for outbuildings, baths, gazebos, verandas, etc. The wood must be treated with antiseptics. The foundation is better columnar, if you want to make a more durable tape, then it is necessary to provide for air vents in advance for natural ventilation.

How is this floor made?

Step 1. Remove the fertile soil layer. It can be added to the beds or level the area in front of the house.

Step 2... Mark the posts. The distance between them is selected taking into account the load and the size of the log. The posts can be made of concrete, block or prefabricated. The dimensions of the supports are approximately 40 × 40 cm, the burial depth is within 30 cm. A layer of sand ≈ 10 cm thick should be poured onto the bottom and tamped down.

Step 3. Fill the supports with concrete. To prepare concrete, two parts of crushed stone and three parts of sand should be taken for a part of cement. Water is added as needed. In the ground, the formwork can be omitted, a formwork from boards or OSB scraps is installed above the ground level. During the manufacture of the formwork, you need to use a level, all edges must be strictly vertical.

Practical advice. It is much easier to make columns from ready-made blocks. The horizontal alignment should be done along the rope. After the extreme ones are exposed along the water level, a rope is pulled between them. Deviations should not exceed ± 1 cm. This spread is eliminated during the installation of the lag.

Step 4. Start fixing the lag, you also need to start work from the extreme ones. Shims can be used for accurate horizontal alignment. It is undesirable to take wedges made of wood, over time they will dry out and wobble will appear: the floor will begin to creak unpleasantly while walking. Between timber structures and concrete surfaces it is imperative to lay two layers of roofing material for reliable waterproofing.

Step 5. After the extreme logs are laid, a rope is pulled between them and all the remaining ones are laid under it. The lags are fixed with metal squares on dowels and screws. To increase stability, it is recommended to install them on both sides. Floor boards can be laid directly on the joists or a sub-floor can be laid beforehand. The final choice depends on the characteristics of the operation and the purpose of the premises.

Always select the joists with a margin of safety, especially in cases where the installation method involves bending loads. It must be remembered that it is always much more expensive to correct mistakes made during the construction of floor coverings than the production of work. quality materials and in compliance with the recommended technologies.

Choose your log boards carefully. They must be absolutely healthy without any signs of rotting. The presence of through cracks and rotten knots is completely prohibited. If there are large healthy through knots, then you need to install the logs in such a way that there is an emphasis under them.

When attaching the lag, do not allow the likelihood of wobbling.

Most of the lag wobbling causes very unpleasant squeaks of the flooring while walking. To eliminate such phenomena, floor coverings will have to be removed, this is long and expensive, it is not always possible to keep the dismantled materials in a suitable reuse condition.

Video - Installation of a wooden floor on logs

Despite the fact that wooden floors have a shorter lifespan and are susceptible to negative effects various factors, many consumers prefer them. After all, they are lightweight, reasonable price and environmental friendliness. Lumber on the floor is one of the most popular options in suburban construction. The basis of this whole structure is the floor joists, which are also made of wood. Although today some manufacturers offer lags from polymer materials, which are superior to wooden ones in many respects.

Why are lagged floor structures so popular?

Reasons for the popularity of lag designs

They have a number of advantages:

This design has excellent thermal insulation properties... By the way, you can put an additional one under it. thermal insulation material.
The price availability of lumber and the minimum costs for them.
The load on the foundation, floor joists or concrete slab is minimal. This creates a free space under the wooden floor that can be used for laying communication networks.
The ability to raise the floor plane to any level. Sometimes designers use this to create tiered floors.
Rapidity assembly process if compared to styling cement-sand screed where you have to wait for it to dry. In addition, you can do the installation yourself, thereby saving a decent amount from the family budget.
Due to the wooden floor, it is possible to create a certain microclimate inside the premises.

With the floor installed on the lags, you can avoid the large money and time costs associated with leveling processes. After all, this design itself performs leveling functions. The emptiness under the plank floor is a kind of ventilation duct, guaranteeing the long-term operation of the structure. But experts still recommend processing wood materials antiseptic compounds.

Design and technical features

Immediately, we will make a reservation that you can lay the floor on the logs regardless of the base in your house. It can be ordinary soil, floor beams or concrete slab... The design in all versions is approximately the same with small deviations, which mainly concern the lag attachment.

If we talk about what the logs are, and what they are made of, then these are the transverse beams on which the wooden topcoat is installed. Currently, the most popular logs are made of wood or plastic. Less often - from metal or concrete products. Wooden elements are chosen because of their low cost, and polymer ones - because of the speed of the installation process and ease of installation.

Attention! If, for some reason, it was not possible to purchase a wooden beam for the lag, you can use double boards as this element. They are usually laid on the edge. In terms of its strength characteristics, a double board is in no way inferior to a bar, and if you take boards of a large section, then their quality increases significantly.

Beginning of work

Suburban developers always face the question of the strength of the lagged structure. How to choose the right section of the timber for the logs? Experts say that for this you will have to take into account several factors regarding the construction of the floor as a whole. Here you have to take into account the span, which means the size of the area of the room, the thickness of the boards to be laid, and so on. But one indicator should be unchanged - this is the ratio of the height and width of the beam itself. It should be 2x1.5. That is, the height of the timber should be a multiple of 2, and the width of 1.5.

For example, a timber of 70 × 100 or 150 × 200 millimeters is selected. In the event that the floor is arranged along wooden floor beams, then the wider the distance between the beams, the more the lags in the section should be.

Pay attention to the location of the ventilation gap. The distance between the finished wooden floor and the heat-insulating material between the joists must be at least 2 centimeters. And it is better if this figure is 3-4 centimeters. So you need to acquire lags taking into account this gap. If the floor is mounted on logs that are installed on the ground, then you will have to take into account the size of the cranial bar, which is attached to the structure from below and creates the necessary roll.

Some masters advise purchasing a bar with a section margin so that it can be reduced as needed. But such an operation is beyond the power of a layman, so it is better to acquire material exact dimensions, and when leveling, use shims. If the lag structure is built on the ground, then brick posts are suitable for leveling in the plane. But keep in mind that it is better to use red brick of the M100 brand for this. You can also use silicate material, but you will have to find information about the depth at which groundwater... If this indicator is below 2 meters, then use it without problems.

A few words about laying the lags in columns. Most important point- This is the definition of the distance between the rows of laid beams. Be sure to pour a small foundation measuring 40x40 centimeters under each brick column. Sometimes flooded strip foundation under one row of columns. The minimum number of bricks in a column of one layer is 2 pieces.

Installation step

Insulation between the lags

This constructive indicator is one of the most important. It is on its basis that the calculations of the amount of materials are carried out. There is one contradictory feature here. If you choose the distance between the lags big size, then the deflection of the elements of the finished floor will be greater. He will not be able to withstand heavy loads. This means that you will have to increase the thickness of the floorboards. And the shorter the distance, the thinner the boards. This suggests that if you want to save on the number of beams, you still have to buy expensive boards.

For example, if you purchased boards 24 millimeters thick, then the distance between the lags should be 30-40 centimeters. If the thickness of the boards is 50 millimeters, then the distance between the logs can be made 1 meter. Traditionally in private country houses a 40 mm board is used, hence the standard distance between the elements of the lag structure, equal to 70 centimeters. In any case, each developer must decide for himself what size floor elements he needs.

Attention! The distance from the wall to the first element should not exceed half the distance between the joists. Traditionally it is 20-25 centimeters.

How to orient the styling correctly

The orientation of the structure in space is an important component of the installation process. What do you need to know for those who assemble the floor with their own hands?

The direction of laying the finished wooden floor - boards - should be along the room, that is, perpendicular to the wall where the window is located. Thus, natural light should not create shadows that can be generated by the laid boards. Then the floor will appear monolithic.
In those rooms where the permeability is very high - a corridor, an entrance hall, a vestibule - the boards are laid along the direction of movement.

Accordingly, the logs are installed perpendicular to the boards.

Mounting methods

The creak of the wooden floor on the logs can be an unpleasant surprise.

More recently, lags to concrete floor fastened with ordinary nails. But this type of fixation was not the best and most durable. Today, additional fasteners in the form of metal corners are increasingly used. of various shapes... What does the instruction for this fastening method say?

For fastening wooden structures, only self-tapping screws are used.
The depth of penetration of the self-tapping screw into the wood is 3-4 centimeters.
If the lag is attached to a brick or concrete post, then dowels are used instead of self-tapping screws.
Sometimes, instead of corners, "P" -shaped are used metal constructions, which are a strengthened version of the former.

Sequence of installation work

A lagged structure can be built after raising the walls, but the boards themselves are mounted only after all the roughing has been carried out finishing works in the form of plaster and putty, as well as after the completion of painting processes.

The sequence for erecting the floor on the ground is as follows:

First of all, the soil is tamped, and crushed stone is filled with a layer of 5 centimeters. This creates an incompressible base.
Formwork is installed under each support, and small foundations are poured. After they dry, brick columns are erected. Please note that there must be waterproofing between the post and the foundation - roofing material, roofing felt or bitumen. It is laid on the posts upper layer waterproofing. You can also install a soundproofing pad.
Lags are installed and fixed. A prerequisite is exposure in one horizontal plane. A cranial bar is attached to their lower edge. A sub-floor is mounted on bars, for which you can use cheap lumber.
A layer of waterproofing material, thermal insulation material, another layer of waterproofing roll material are laid, and the boards are installed as a final floor. Please note that the boards should be located two centimeters from the walls. This gap will compensate for the expansion of the lumber due to changes in indoor humidity and temperature.

Adjustable floors

If wooden floors are assembled on beams or on a floor slab, then many processes disappear, which reduces the time of work and the number of necessary materials... For example, brick posts will not be needed.

Modern approach to many construction processes, including the construction of a wooden floor, has led to the introduction of improved materials on the market. For example, the logs were supplemented with special lifting mechanisms, with the help of which you can easily and quickly change their position in space. Such a mechanism is a rod, which is based on a threaded bolt-nut connection. The rod has two supporting plates supporting the floor and the beam itself. By rotating it, you can raise or lower the edge of the log. According to many experts, this is very convenient device, several times reducing the time for setting the lag in one horizontal plane.

Conclusion on the topic

It may seem to many that properly laying a wooden floor is not so difficult. But this is only apparent simplicity. You have to work hard to install the floor joists correctly. In addition, the complexity of the process will depend on the installation technology. If the structure is installed on the ground, then there will be a lot of work. In addition, the foundation poured under the supports must be dried, which increases the time of work.

Ruslan Vasiliev

Modern technologies in construction, these are unique opportunities. For many, words such as bridging and polymers, tape flooring, GOST, pedestals, column connections, dimensions 100x200, or 150x50 do not say anything. But those who have already encountered repairs know that it comes most likely about the field on the logs. Someone just wants to make the floor reinforcement, while someone needs to lay a new, durable and beautiful one. And very often the technology of flooring on logs is used.

It should be said right away that laying the floor on the logs in many cases is simple perfect solution... Indeed, this method has many advantages. It is very important that the floor is warm.

It is also worth making the floors on the logs as:

Noise from downstairs neighbors will not penetrate you;
Installation can be completely done by hand;
The cost of flooring and work is quite acceptable;
Wires and pipes, not very attractive, but necessary, can be hidden under such a floor;
This is an eco-friendly floor.

When you work, the smell in the room will be very pleasant. For many, by the way, the smell of processed wood is a real antidepressant, which by itself raises your spirits and sets you up for work.

Lags are called beams that are needed as a support for a hard floor covering. Logs can be made of metal, polymers, reinforced concrete, but usually wooden logs are taken. Wood is easier to work with and cheaper.

Lags differ from beams in mobility and smaller dimensions. Beams after installation, if you give a figurative example, cannot be moved, but logs can. And it is much easier to mount them, and if repair is needed, it will be simple and quick.

Installation tools: installation of floors along the logs in the house

For work you will need a hammer, level, screwdriver or drill, knife. The materials for the manufacture of such a floor are taken as follows - pieces of chipboard or plywood, any insulation, self-tapping screws, corners or U-shaped fasteners.

To prepare the floor for installation, the entire floor area must be cleared. Check old screed, if the concrete floor is already devoid of integrity, it needs to be patched up. Then debris and dust are removed, everything should be clean. Then you need to eliminate the defect in the subfloor. The floor should be primed. How many pros do not say about the need for a primer, there is some kind of careless attitude to this procedure. The primer is right, it must be absorbed and dry, and only then the flaws are filled.

Then, from the level, the maximum point of the surface in the room is calculated. You need to set a mark so that this is a guideline for subsequent work. And then the work develops according to two possible scenarios: to make a screed, bringing the surface to one level, or to expose the logs to the level with small plywood gaskets.

Step-by-step instructions: installing a lag for the floor with your own hands

It all starts with the fact that solid or connected bars are laid out across the width of the room. The first bar and the last will be located 20 cm from the wall. You need to calculate the step between the lags in advance.

It is necessary to deduce the floor level, from of this moment the quality of the topcoat will depend;
All bars must be placed in one horizontal plane;
For lifting, lining of bars or plywood is used;
It is not enough to install, you need to fix the lags, for this, either self-tapping screws are used, or anchor bolts are installed;
The length of the interval of fastenings is 70-80 cm, you drill the timber, grabbing concrete foundation, tighten the self-tapping screw.

There is an option of installing a lag and on an adjustable fastener, turning it, you will achieve the desired result. By the way, if topcoat there will be not a wooden floor, but ceramic tile small, then the distance between the bars will be 30 cm. Only in this situation there are also transverse logs, and at the same distance. They need to be fixed at an equal level with the longitudinal bars (a corner is used). This reinforcement of the structure must be used, because the size of the tiles is small.

Modern floor logs: the size of the timber

The reliability of the structure depends not only on whether you use a board or metal elements, but also on whether the calculation is correct. First, the length and thickness of the bar are determined. Length is the length and width of the house. In this case, it is imperative to leave a gap, and the timber, accordingly, is selected 20-30 mm less.

Such ventilation gap necessary - it prevents deformation if changes in humidity and temperature occur.

The cross-section of the timber, its size is more difficult to calculate. The potential load on the floor is important here, as well as the size of the spans between the direct pivot points of the log data. There is a table that makes the calculations easier. The larger the span, the thicker the timber will be. For example, the size of the span is 3m, which means that the section of the lag is 150 by 80 mm. The sectional shape is usually rectangular. The beam is installed on the edge so that the logs can withstand high pressure.

What is the distance between the floor lags

The lag step will depend on the thickness of the flooring. If you are using solid thick planks, the joists can be attached relatively rarely. Well, subtle and not special durable coating requires more lag.

Dependency can be seen with a couple of examples. For example, the thickness of the floor board is 30 mm, which means that the interval between the lags is half a meter. Or a thickness of 40 mm, therefore, the step between the lags is 700 mm.

The most accurate calculation is not needed. It will be sufficient to simply take the distance between our lags of the averaged value. And if at the end of the installation you saw that the distance is inaccurate, then make the step between these last lags less, and the structure will be strong.

Timber size: floor logs

The length of the timber should be approximately 3 cm less than the width and length of the room where the floor is laid. The length of the lag must necessarily be less than the length of the room in order to avoid deformation of the structure if temperature drops occur. It is good to make logs from solid materials, but sometimes the bar needs to be lengthened.

Two elements are spliced according to the rules:

Under the splice there should be support elements eg pillars;
If adjacent logs are spliced, then the splicing points are positioned relative to each other with an offset.

The connection must meet these conditions, otherwise there may be a threat of low floor rigidity in the very place where the timber is spliced. Adjacent logs are spliced with an offset of a meter. This fact affects the size of the beams taken.

Algorithm: laying the floor on logs with your own hands

You need to lay a wooden log from the corner of the room. Then, the first row is usually placed with a tongue and groove relative to the wall, and in this case, the gap between the wall and the log should be equal to 1 cm (to avoid deformation of the wood). Then a row of lags is laid offset relative to the first lag, by about several bars.

In order for the boards to be firmly attached to the base, you need to knock a little on the wood with a construction hammer. This is necessary for secure fastening. Boards are attached along the wall, fixed with screws. The screws can be on the surface, it doesn't matter, they will be covered by the baseboards.

Hint: how to strengthen sex lags

Everything here is individual, but some general rules there is. For example, if there are floor joists and a strapping on the same level bottom bar, then you can fasten them together with forged staples, or perforated corners will help. If the logs are located below the strapping bar, then a rack-mount bracket is used, metal.

Roughly speaking, the main purpose of reinforcement is to rigidly fix the log of the floor and beams. lower crown... In this case, when the flooring is strengthened, the floorboards will stop moving apart. Also, as an option, you can rally the floors until the gaps are eliminated, and the gaps are simply covered with baseboards.

How to put logs on the floor (video)

Today, when the floor can be laid, filled, made polymer coatings, use plastic parts, blotches of bricks, etc., from classic ways many refuse to repair. But sometimes, instead of complex and expensive structures, old and proven methods are required. The same floor on logs, which will "make friends" with both wooden and brick houses.

The device of even and solid floors is considered one of the main issues when carrying out repairs in a residential building or building a new house. Homeowners in modern conditions have many options for flooring, relying on new technologies in production building materials... There are a huge number of construction compositions synthetic or mineral based. However, as before, many homeowners still prefer to make floors by laying a wooden covering on logs, according to the old, time-tested technology.

Of course, the technologies of modern manufacturers of building materials have also touched the floors on the logs, but the principle of construction itself has remained unchanged. Exactly reliability and simplicity make such a flooring device in demand and popular and now. Such a floor covering is able to do it yourself House master not very highly qualified, showing attentiveness, patience and accuracy, using the necessary control, measuring and working tools.

What are floor logs and the benefits of their use

Crossbeams, which are the basis for installing wooden floorboards or other floor sheeting in the house, are called logs. Modern construction technologies allow the use of concrete, metal and polymer materials for the construction of structures, but still traditional material wood remains in production.

Wooden logs for the house can be different designs and thickness. The most convenient to use is considered wooden flat bar required size. The use of a bar greatly simplifies the setting of the level required for a given surface, and the assembly process of the structure is more accurate. Used to make structures and boards, if installed on the edge. The required thickness of the log is obtained by connecting several parts together. Sometimes beams are made of round timber, and it is necessary to trim at least one side in order to achieve a snug fit of the battens or floorboards.

Of course, wood is inferior in strength to a cement coating, but still the construction of a floor using a lag has its advantages:

The construction with logs is much lighter than a concrete floor, with an equal floor lift.
If the assembly is done correctly, then the floor on the logs is well ventilated, which serves important factor such coverage.
It is very easy to place various hidden communications(electrical wiring, pipes). If it is necessary to eliminate the accident and carry out work on the prevention of communications, access to them is much easier.
It is very easy to insulate the floor in the house, even if there are communications. Almost any type of insulation material can easily fit into the niches between the lags.
Almost without changing the consumption of the material used, using a lag it is very easy to level the surface under the ideal horizontal, even with a large level difference. Application concrete pavement, in such cases, becomes a more time consuming process.
And you can also highlight more high level noise absorption of floors on logs.
Distribution and transmission of loads (dynamic and static) occurs evenly, which has a positive effect on the strength of the base.
Repair work is very easy to carry out using the floor on the joists. It is enough just to dismantle and replace the damaged areas of the coating.
The design feature of the use of lags involves fastening of any type floor covering... It can be not only wood, but also almost any roll material, and even ceramic tiles, if you observe necessary technologies manufacturing.
Modern technologies of building materials allow, even on wooden covering, fix the base heating system.

Choice of wood

The optimal material used in the manufacture of floor logs is a timber, which is cut on a special machine in accordance with the size. Usually, for the manufacture of timber, not very expensive wood is used - spruce, fir, pine. Hardwoods are used much less often, because they have a high cost, although they have the best performance.

The use of wood first and top grade is impractical, the use of second-class wood is sufficient. The use of a bar made of wood of the third grade should be taken with caution, since it contains knots that negatively affect the strength of the material.

The section of the bar must have a strictly rectangular shape.... Deformed, bent or twisted bars are very difficult to level. The timber must be dried to a moisture content of 12%. It is undesirable to use a wetter material, as it can warp after complete drying.

The usual height of the timber should be 1.5–2 times its thickness.

The following types of wood are used for flooring:

The flooring made of pine, spruce and fir is used in rooms with low traffic, since these types of wood are considered soft and mechanical damage easily remains on them.
The most durable material is oak. Its application, possibly, in any premises, even in industrial and office. But not very frequent use of this material is due to its high cost.
Siberian larch, due to the presence of resins, does not rot, therefore it is often used for floors in baths. Has the same hard structure as oak.
Alder and aspen are good for use in children's rooms and bedrooms, since this wood is considered beneficial to health.

The type of wood is often selected depending on the planned coverage of the boards. Gathered to paint the floor - you can take the second grade of boards. For varnishing, it is necessary to use boards of the first grade. And in utility or technical rooms, the floors can be laid with boards of the third grade.

To protect wooden structures from mold, mildew, bugs, decay, it is necessary to pre-treat them with an antiseptic.

Dimensions of the lag for the floor

The reliability of the entire coating system directly depends not only on the material that you have chosen for the manufacture of the floor, but also on the size of the timber. Therefore, even before tackling the issue of buying a bar, it is necessary to calculate the size of the required material:

The length of the lag directly depends on the area of the base itself. At the same time, it is advisable to choose the size taking into account the technological gap, the distance from the wall to the beam should be about 3 cm. This gap is arranged in order to avoid deformation of the frame during thermal expansion of the material.
Lags have a rectangular cross-section, and fit when mounted on the edge. Therefore, the size of the width should formally be half the height.

Installation of a lag for a floor

The device of the floor with the use of a lag can be made on various bases. In this case, it is imperative to take into account the properties of the base, the magnitude of the load on the surface and some features of the installation of the structure.

Installation on wooden floors

When installing a floor with such ceilings, the joists are attached to wooden beams. Due to the fact that the beams may not have a perfectly even level, they are attached to the sides of the beam. With this installation, the use of pads is not necessary. The horizontal is checked with a level control rod. It is better to fix the logs with screws with a diameter of at least 6 mm, and a length of 2–2.5 times the width.

To prevent cracking of logs and beams, you first need to drill holes with a drill with a diameter of 2.5 mm less than the diameter of the screw.

Installation on concrete

There are two ways to install structures on a concrete base:

Before installing the logs on a concrete base, you need to do several preparatory operations:

Since concrete perfectly absorbs moisture, a layer of waterproofing must be placed on the base.
Then apply a layer of sound insulation, which is necessary to eliminate impact noise.
Screed, either dry or cement.

Insulation must be laid strictly between the logs, preventing material from getting under them.

Installation on the ground

First you need to make leveling the soil surface and compacting it... This work is mostly done manually. Then it is necessary to mark the distance for the posts for the lags. The distance from the wall to the first log is from 3 to 20 cm.

After marking the location support pillars it is necessary to make a foundation for these pillars.

The foundation for the pillars is done as follows:

After complete drying of the concrete, we carry out waterproofing with pieces of roofing material. Then we lay the bricks directly on the roofing felt. Usually the foundation is calculated so that two rows of bricks are enough, and the top row should be located perpendicular to the length.

Then we carry out waterproofing on a brick from pieces of roofing material. On top we lay a gasket from soundproof material, we fix it so that it does not move out.

For the device of the floor, it is necessary to achieve a perfectly flat surface, for which we carefully calibrate the horizontal lag. The first to install the logs extreme from the walls and at a distance of two meters from each other. Then we lay all the intermediate logs and fasten them.

Floor device

Previously, before laying the finished floor, you need to make Painting works on the walls of the room to prevent contamination of the boards.

After installing lag you need to perform floor insulation operations... The insulating material must be laid between the joists. The insulation is laid directly on a solid base. And if the logs are arranged on the ground, then the insulation must be laid on the rough floor.

The floor begins to creep from the corner of the room farthest from the door. The first row of boards is laid at a distance of 10 mm from the wall, with tongue-and-groove to it, so that the expansion of the tree during use can be compensated. We fasten the boards to the lags with screws.

If the size of the floorboards is less than the length of the room, then the next row is laid with an offset. We insert the floorboard into the groove of the previous row and fasten it with a screw so as to hide its cap. So, consecutively, all the boards are tightly pressed against each other and must be fixed to all lags. The last row of floorboards is fastened with screws so that later you can close their caps with a plinth.

The device of the floor along the logs is one of the most common. Such a wooden floor is easily repaired.... If you carefully monitor the correctness of the lag laying process, then such a structure will turn out to be strong and durable in operation.

For high-quality arrangement subfloor in 80% of cases use logs. With the help of beams, you can not only make a strong wooden lathing, but also level the rough base. What should be the height and width wooden beams? The article will consider the relationship between the main parameters of the lag, as well as the ability to withstand static loads on the floor.

Basic requirements for floors

A log structure for arranging a subfloor must have a very high strength. Only in this case, it does not deform when exposed to static and dynamic loads created by the topcoat (laminate, ceramic tiles, solid board, parquet), furniture, equipment and people. The size of the floor beams is determined by the intensity of the load on m 2 of the floor, which is created during its operation.

The calculation is performed in accordance with the following defining parameters:

When arranging timber frame for attic floors the floor must support a weight of 105 kg / m 2;
When finishing rough foundations on interfloor and basement ceilings, wooden floors should not deform even with a load of 210 kg / m 2.

Based on the above nuances, a calculation is made, according to which the main dimensions of the lag are precisely determined:

section;
length;
thickness;
width.

It is very important that the necessary parameters are observed, otherwise, due to the high static load, the wooden crate and the floor board will begin to bend. This is fraught with complete destruction of both rough and finish coatings.

Features of the materials used

Theoretically, logs can be made from almost any material:

metal;
plastic;
wood;
compound.

But the rather high price of most of the above building materials makes them uncompetitive in comparison with wood. That is why, as a rule, a thick board or timber is used to assemble a wooden frame. But this material also has one significant drawback - hygroscopicity.

Therefore, in the process of choosing beams for arranging the floor, it is advisable to choose only that species of wood that is subject to decay and deformation to a lesser extent. Which wood to give preference to? The best option larch will become, but it is quite expensive. A more affordable alternative would be pine or spruce. At the same time, resin pockets and minor defects on the timber do not affect its technical performance in any way.

But do not forget that the material must be strong and resistant to deformation. Based on this, it follows that you cannot save on the strength of the lag. The moisture content of the wood should not exceed 20%, otherwise, during the drying of the wooden frame, the logs will bend, which will affect the horizontality of the laid finishing coating.

Section lag

The calculation of the optimal section (thickness) of the log for the subfloor is carried out taking into account the following parameters:

The width of the span between adjacent support points.

Important! To assemble a wooden frame, use logs with rectangular section... In this case, the large side of the beam should be located vertically. Thus, the floors become more rigid, which minimizes the possibility of deformations.

To understand what the cross-section of the timber should be for different spans, consider the typical dimensions of the beams for arranging the floor in residential premises:

In other words, the calculation of the optimal section is determined by the following expression: the height of the beam should exceed the width by about 1.5 times. However, there are some nuances here that are worth knowing about. The large thickness of the board inevitably affects its price. To reduce the cost of buying a log with a large section, in the process of arranging a wooden frame under the beams, you can make supports of concrete or bricks. If the supports are placed at intervals of about 1 m, the thickness of the timber can be reduced by two.

In some cases, the thickness of the lags is determined by the type of material from which they are made. Very often, when arranging the floor of the second floor, high-rise buildings are used as beams reinforced concrete floors. Optimum thickness metal elements is determined by the index of its flexural strength.

Linear dimensions of beams

Length and width are the main parameters that must be considered when choosing beams for arranging a wooden frame. How to make a competent parametric calculation?

Determination of the width. As already noted, logs with a rectangular section are chosen for the subfloor. During the installation process, they are laid on the edge to give the structure more rigidity. In this case, the formal width of the beam should be 2 times less than the height;
Determination of length. The length depends on the area of the base itself. However, it is advisable to select the size of the lag taking into account the technological gaps - the distance from the beam to the wall should be about 3 cm. The gaps are made in order to avoid significant deformations of the wooden frame during thermal expansion of the material.

Determination of the step size for laying lags

Calculation of the optimal step for wooden beams it is rather difficult to define. If between the section of the beam and the size of the span there is a straight line proportional dependence, then with the interval of laying the beams, the situation is different. A simplified version of the calculation should be as follows: the step between the lags is the greater, the thicker the board, which is laid on the wooden crate. Why is that?

The explanation of this rule is easy to understand: the thicker the board is, the less it will undergo deformation. However, it should be borne in mind that the interval between the layout of the beams does not depend in any way on the material from which they are made. Indeed, in this case, we are talking about the ability of the board to withstand static and dynamic loads.

How to calculate and determine what the step size should be? To do this, consider a simple formula:

Base length = distance between beams + gap between beams and wall + beam width. For clarity, let's analyze an expression with numeric substitutions:

10 m = 0.6 m * (T-1) + 0.03 m * 2 + 0.07 m * T, where T is the total number of beams. In this case, the expression T-1 is the step between the bars, laid at a distance of 60 cm from each other. In the course of easy calculations, we will find out that T = 16 (beams). That is, to construct a sub-floor from a log, a total of only 16 beams are required.

In this case, the sum of the intervals between the beams will be: 10 - 0.06 - 16 * 0.07 = 8.82 m. Now the resulting expression should be divided by the total number of intervals: 8.82 / 16 = 0.55 m. In our case, for assembly wooden lathing the logs should be installed in 0.55 m increments.

Conclusion

When finishing the subfloor, logs are very often used. But in order for the base to really last a long time and not deform, it is necessary to take into account the linear dimensions of the beams (section, width, height). These parameters are determined by the expected degree of load on the floors and the width of the spans between the supports on which the joists will be installed.