How to correctly calculate the distance between the lags of the floor? Calculation of building materials for a wooden floor device - online calculator A large distance between the lags what to do.

Wooden structural materials, combining high strength, environmental friendliness and ease of installation, are widely used in modern low-rise construction for the construction of roofs, ceilings and the power frame of the floor. A correctly calculated distance between the floor lags and interfloor beams is the key to the strength and durability of not only a single structural element, but the entire structure as a whole.

What are floor joists?

Floor logs, made of a wooden beam of a certain, precisely calculated section, are power elements that perceive static loads from furniture, equipment installed on the floor, and dynamic loads that occur when people move indoors. Floors on wooden logs have some features that allow leveling minor flaws in building structures:

Uniform distribution of the load on the underlying building structures;
Increase the overall strength of the floor or ceiling;
Improvement of soundproofing properties with the formation of an additional heat-insulating layer;
Possibility of stacking engineering communications with relatively high maintainability;
Low installation complexity, providing a flat surface for flooring from sheet or roll materials and flooring from natural wood valuable breeds.

Logs are made mainly from coniferous wood, the resin content of which provides protection from moisture and a long service life. For the installation of logs in difficult-to-use premises, hardwoods with high moisture resistance or larch products with a high content of natural resins are used.

Why is it necessary to calculate the distance between the lags?

Like any other structural material, wooden crafts have certain indicators of strength, wear resistance, service life and, of course, prices. When installing wooden floors on logs or interfloor beam ceilings, you can also use thick logs laid at a close distance from each other, obtaining the highest structural strength and spending a fairly significant amount. But use required amount a log or beams having a cross section corresponding to the intended load will make it possible to obtain the necessary structural strength at a much lower cost.

IN panel house when the logs are laid on the surface of a reinforced concrete floor slab, their cross section is selected to be the minimum necessary for fixing the floorboard or chipboard. Another thing is the application wooden structures in frame structure when the logs perform the function of not only the basis for the future floor, but also serve as a strength element of the frame associated with wall supports.

Main calculation criteria

The thickness of the floorboard or board materials OSB, chipboard;
The number of support points or the distance between the walls;

Even with such minimal data, it is possible to correctly calculate required section wooden beam for the manufacture of logs and the maximum step between the logs.

Bar section

The cross section of a wooden beam for the lag device is selected depending on the distance between the supports and the required load capacity of the floor. When calculating the required section of the lag, the maximum load on the floor should be no more than 300 kg per m 2.

As a log, a square or square bar is used. rectangular section, the wider side of which is located vertically. Thus, the maximum rigidity of the log is obtained with a minimum consumption of wood, which reduces unproductive costs for flooring. In construction practice, the ratio of the width of the log to its height is 1.5-2, which is optimal in terms of strength and cost. When used as a standard log edged board 5 cm thick, its height with a gap between supports of 2 m should be from 10 to 15 cm. Standard sizes lag depending on the span are presented in the table:

Sometimes it is difficult for an individual developer to find a standard timber suitable for the manufacture of logs of the required section. The way out of this situation is quite simple. To ensure the required load capacity of the floor, several standard boards 5-6 cm thick can be installed side by side, increasing the height of the resulting timber by 1-2 cm relative to the standard one. Such a “layer cake”, even in the absence of fastening the boards to each other, completely replaces a full-bodied timber of the required dimensions. Similar results can be achieved if the boards are placed at regular intervals along the entire length of the supporting surface of the foundation.

The only thing to consider is frame house it is quite difficult to apply this method of load distribution due to the binding of the log to the racks wall structures, openings and distribution of insulation. In a frame house, floor logs are used as beams interfloor overlap, therefore, the minimum required cross section must be increased taking into account the load from ceiling structures and a heater.

Step between lags

In the manufacture of wooden floors, it is clearly seen how the distance between the lags, called the step from the thickness, and the type of materials used depend. The thicker the board used as flooring, the greater the distance should be between the lags. More clearly about which step to choose when using different thickness boards, the table below shows.

As a draft floor covering in modern construction very often slab structural materials are used instead of boards, which accordingly changes the calculation method. Chipboard (chipboard), cement particle board(DSP), oriented strand board (OSB) and gypsum fiber boards (GFP) are successfully used as a base for a coating of rolled materials or ceramic tiles, arranged on wooden logs. In some cases, chipboard can be additionally covered with materials on cement or plaster base. Considering the greater bending rigidity of chipboard and less strength than the board, you should choose a step between lags no more than 40 cm, and when using a thicker chipboard (20-22 mm), increase the step between the lags to a maximum of 60 cm.

When calculating the step between the lags for a particular room, you can use the average table values, and if the distance between the last lags is less, then the strength of the floor in this place will only increase.

Consequences of calculation errors

What happens if you choose the wrong section of the lag and the step between them? When arranging floors according to concrete base most important parameter there will be a step between the lags, on which the behavior of the finish coating depends. chipboard, fixed on logs installed with a larger gap than allowed, may sag or break, ceramic tile- crack, and the board - bend. In any case, the floors will require alteration.

More backfire come from errors in calculating the required number of lags used as interfloor floors. If should be used large quantity log or their larger cross section than indicated in erroneous calculations, the strength of the entire structure is significantly reduced, which can lead to irreversible deformations and complete destruction of the floors.

Calculation methods

To calculate the dimensions of the beam and the number of elements required for the installation of a wooden floor on logs with rough coatings from a board or chipboard, you can:

Contact the design organization, which will professionally calculate how many elements should be covered from a board or chipboard, and what size of timber should be used during construction;
Use special averaged tables on your own, choosing which value is closer to the required one, leaning upwards if there is no exact match between real and tabular sizes;
Use computer programs and online calculators into which a sufficiently large number of parameters are entered, and the program will accurately determine required dimensions timber and the distance through which it must be installed.

There are many DIY floor leveling solutions. An exception is not laying the floor with the help of wooden logs. This method of floor installation is very popular due to its environmental friendliness and practicality, and the naturalness of the materials creates warmth, comfort and a welcoming atmosphere. The wooden floor has always been valued both for arranging in country houses as well as in apartments. And if the choice fell on a wooden floor on logs, you should decide what kind of wood to choose, how to install the logs for the floor in a particular room, their size, amount of material, and so on.

Scheme of the device of a wooden floor on the ground on logs (with heaving soil)

The main purpose of the lag is to obtain a flat surface for subsequent finishing works in the House. In addition, they help to maintain a full ventilation mode of the lower part of the floor, which prevents wood decay. This is especially important if the floor is laid on the ground, from which dampness appears. The space between the base of the floor and the flooring prevents dampness and improves sound insulation. In addition, there are other functions:

Communications can be placed in this space, which spoil the view if they remain on the floor;
Logs ensure uniformity of the load on the foundation;
There is an opportunity for, the types of which are many. Expanded clay, sawdust, mineral wool and etc.;
It is possible to adjust the height of the floor;
The beam allows you to get a solid floor due to the support points;
Mounting on joists guarantees a quick and easy installation that even a novice can do.

The lags are wooden beam, which is laid on any base or directly on the ground. Most often you have to use a beam with an aspect ratio of 1:1.5 and 1:2, but there are other section sizes. It all depends on the characteristics of the overlap and load.

Pine timber and the section used for the floor log

It is better to buy a ready-made timber, but making it yourself is also not excluded, the main thing is to choose the right wood. Its ideal moisture content is 18-20%. At higher values, deformation of the finished floor will occur after drying.

The most popular material is pine. You can also use spruce and fir. There are no special requirements for the very quality of the tree; the beam can be made of material of the second or third grade.

There are options for making logs from simple boards, which are connected with self-tapping screws and installed on the edge. If very long bars are needed, they are spliced together by creating a lock joint or butt-to-butt. And at the joints, a support is installed, for example, columns of bricks.

The choice of material for the lag

When choosing a base material, it should be remembered that it must be strong, even and have a low rate of deformation in the event of a load. It can be plastic, metal, reinforced concrete, etc. But the most popular material is a wooden beam.

Since there is no need for high quality wood for timber, the choice usually falls on spruce and pine, which are very popular due to their low price. But when installing such a tree in a house, it is better to think over a waterproofing system.

Larch and aspen are more expensive, but indispensable if we are talking about high humidity. Larch is considered the best option if you need strength and resistance to rotting of the floor in the house.

Logs on brick posts and a full floor cake on the ground

If the beam is mounted on a reinforced concrete base, then a layer of foamed polyethylene is preliminarily laid. And if the logs are installed on brick support posts, then polyethylene is placed between the beam and the post, as well as between the post and the ground. Roofing material is suitable for laying between wood and brick.

Before installation, the logs must be treated with an antiseptic to protect themselves from various pests. This is especially true for wooden houses where carpenter beetles can start.

Determination of section and dimensions

How reliable the design will be depends not only on what material is used, but also on the correct calculations. Before purchasing a timber, it is necessary to determine its length and thickness. The length must match the length and width of the house in which the floor is to be installed. But it is better to leave a gap, and choose a bar 20-30 mm less. This is done in order to prevent deformation in the event of changes in temperature and humidity.

With the determination of the dimensions of the cross section of the beam, the situation is much more complicated. The thickness depends on the lag material and on the calculated characteristics of the future floor. The maximum possible load on the floor and the size of the spans between the lag support points are taken as the basis. IN residential buildings It is customary to take an indicator of 300 kg per square meter for the maximum load. m.

There is a table that displays the relationship between the thickness of the beam and the length of the span between its supports. Usually, with a length of 2 m, a beam with a section of 110x60 mm is used, with a length of 3 m - 150x80 mm, and for a four-meter span, a beam with a section of 180x100 mm is used. You can trace the pattern: the larger the span, the thicker the beam.

Dimensions of the lag section depending on the span of the room

The shape of the section itself is usually rectangular. The beam is installed on the edge so that the logs can withstand high pressure. This achieves maximum rigidity of the beam.

But do not get hung up on the ratio table, since the thickness of the lag can be greater if necessary. For example, if you plan to lay a thick layer of insulation.

It should be taken into account the fact that for non-residential premises the load level indicator is more than 300 kg per sq. m. And it will have to be calculated first and only then select the appropriate lags, based on the data obtained.

If the beams are not made of wood, but of metal or reinforced concrete, a smaller thickness is allowed. This is due to the fact that such materials are more resistant to stress, they bend less.

The distance between the lags is selected depending on the thickness of the coating that will be used for the flooring. After all, the thicker the flooring, the greater the step can be between the lags, since a thick coating is less susceptible to deflection when exposed to loads. To establish such a ratio, there is also a special table. With a board thickness of 20 mm, the step is 30 cm; 25 mm - 40 cm; 30 mm - 50 cm, etc. And you can use the following formula: with an increase in the thickness of the beam by 5 mm, the step length increases by 100 mm.

The distance between the lags depending on the thickness of the floorboard

When used or calculations are slightly different. This is due to the higher bending stiffness. Here, for a beam with a thickness of 1.5-1.8 cm, a distance between the lags of up to 40 cm can be allowed. And such materials are attached to the lags in several places. The logs are arranged in such a way that the flooring can be fixed at the edges and in the middle. In this case, the edge of the sheet is laid only up to half the beam, and not over its entire width.

Log laying

Wooden logs can be installed on any base, subject to the installation rules. For the crate you will need:

bars,
Level,
screwdriver,
jigsaw,
fasteners.

When installing the floor on the logs can be used as simple design, so and . In an adjustable design, the screws are able to align the joists. The bars can not be attached to the base of the floor, but there is a risk of destruction of the entire structure due to the displacement of the lag.

In addition to these tools, you may need others. To install a log on concrete or soil, you need a manual puncher. First, supports are installed, for which holes are made up to 10 cm deep, covered with sand and filled with water. A film is placed on the sand, and a brick support is placed on the film, which is covered with roofing material. Bars can be installed on these supports, fixing them to the walls with the help of galvanized corners.

If the basis is wooden beams, it is important to determine the direction of the beam. If the timber is laid across the beams, it is better to fasten the logs with self-tapping screws, treat the beams with an antiseptic, and drill the holes to avoid splitting. With a parallel fastening of the beam relative to the beams, the logs are installed both on top and on the sides.

For the concrete floor, polyethylene foam with a foil layer is used, which creates waterproofing and reduces heat loss. The beam is distributed over the entire surface with a certain step. Next, the base is leveled and the lags are fixed. You can also install the beam using stands. First, the supports are fixed to the ceiling, and the logs are already attached to them with the help of self-tapping screws.

The floor in the house plays a huge role. And in order for it to be even and beautiful, preparation should be taken seriously before installation. When installing the floor along the logs, it is important to correctly calculate their size, the amount of material, the distance between the bars and the parameters of the house itself. If you strictly follow the instructions for laying the floor along the lags, the surface will not sag and creak, but will only bring joy and comfort to the residents of the house. After all, despite the ease of installation, the process of installing such a floor is very responsible. And it is better to constantly monitor all actions in order to avoid errors. If you have something to add, or you want to leave your opinion about the article, write in the comments!

All parameters must be specified in mm

X- The width of the floor.

Y- The length of the floor.

S1- Lag width.

S2- The thickness of the lag.

S3- The distance between the lags.

O1- The width of the floorboards.

O2- The thickness of the floorboards.

O3- The width of the subfloor board.

O4- The thickness of the board.

R- The distance between the boards.

With help online calculator and you can calculate:

Volume of materials lag;
Calculation of the lag for the floor: length, width and required quantity;
Total floor area or quadrature;
Number of rows and volume of floor covering;
The number of sheets of wood, laminate or parquet;
The volume between the lags for insulation;
The amount of material for the subfloor.

Useful information

Wooden flooring is made in three tiers, as shown in the figure above. Below are the bearing logs on which they will lay draft boards, and on top of the finishing floorboards. Below we describe in detail the installation technology.

DIY wooden floor

As a rule, these works are carried out after completion heating season. Since at this time, the boards will not absorb excess moisture. The weather should be dry and sunny. It is best to use a non-planed board for rough flooring. At the same time, milled and dried boards with a longitudinal groove for ventilation are used for the finishing layer. Boards with a figured edge for a mortise connection. As a rule, each such board is pre-treated with a decorative and protective composition.

During the installation process, you must follow the requirements:

All logs must have good stability;
Logs are laid strictly horizontally (except when the slope is provided for by the project);
Ensure ventilation of the space under the floor;
The moisture content of wood should not exceed 12%.

Marking and preparing the floor surface

First of all, we mark out the room, and designate the places that need to be planned in order to achieve a single level (taking into account the thickness of the seams and the height of the brick). For filling incompressible soil, fine crushed stone or sand is used, with a layer thickness of up to 5 centimeters.

After that, we tamp the entire surface. In those places where the logs will be located, we fill in the rubble and also tamp it into the ground.

Installation lag

As a log, you can use a wooden beam measuring 50x100 mm. According to your results of the program, we install the beam on an already compacted surface.

If you plan to increase this distance between the lags, then in this case you should use a larger section of the timber.

If the subfloor base has concrete floor or slabs, then we install the logs directly on the concrete. In this case, you can use a smaller cross-section of the beam, since the bending load is almost completely eliminated. The rough flooring will act as a retainer for the second tier, and therefore a section of 50x50 is sufficient.

The distance between the lags will depend on the thickness of the material being covered. For example, 60 centimeters for a milling board, 40 centimeters for covering OSB or plywood.

When the logs are installed, we proceed to the waterproofing of the space under them with the help of roofing material or other modern material.

Rough layer

When the logs are laid, we begin to install the second level, namely the “draft boards”. To do this, all end joints should be performed directly in the middle of the lags. To fix the boards, we use wood screws of the desired size. You can either press the draft boards against each other or nail them at short intervals. In our case, this interval is determined by the value R.

Nails should be hammered towards each other at a slight angle, for a strong fixation.

If you are laying with milling boards, it is not enough to press them together by hand. For this, special stops and wedges or tightening devices are used.

To fix the finishing board, we use nails or wood screws.

Hats of fasteners should not be higher than the surface of the board. To do this, you need to go deeper by 2 millimeters. The recesses can be treated with a special putty before painting the floor.

If you are using screws instead of nails, you will need to drill holes and subsequently countersink each recess.

In the process of laying between the wall and the end of the log or the end boards, it is necessary to leave a gap of 10-15 millimeters, which will subsequently be closed with a plinth. This gap will serve as a compensator in the process of thermal expansion or moisture swelling.

The flooring is ready, now it can be covered with stain or protective varnish.

Let's start with what is overlap?

An overlap is a structure that separates adjacent rooms in height.

talking plain language, overlap is a structure for the formation of floors, both for separating living quarters from the attic and basement, and for separating living quarters. Interfloor, basement, basement and the value of the withstand load are distinguished from each other (it is determined by the type of beams and the distance between the floor beams), as well as the sheathing of the beams.

Reinforcing cage for a monolithic floor slab

Cover requirements

The structure must have the necessary strength in order to withstand not only the load of its own weight, but also additional - such as the weight of people, furniture, equipment. The value of the expected load per square meter of flooring is determined depending on how the room is used.

The corresponding calculation is performed. Here are the loads:

for the basement and interfloor - at least 210 kg of load per sq. m of floor area.

Based on this, it is determined which timber to use and how to lay it.

load on one square meter basement ceiling must be at least 210 kg.

Ceilings must be sufficiently rigid so that deflections do not form. Wooden floor beams can be used as logs for the floor of the next floor. To determine which timber to use, you need to touch the resistance mat a little. Such a lag calculation is usually performed by architects, and those who want to build with their own hands use tables.

When renovating or building a new room division element, sound insulation must be taken into account. How to do this and what are the requirements for soundproofing - this is determined by regulatory building documents. This requires carefully closing existing gaps at the joints of structural elements and using appropriate materials to fill the gap between the beams.

Ceilings that divide the room, having, at the same time, a difference in temperature, must comply with heat protection requirements normative documents. To do this, we use heaters that fit between the beams. Their number determines the calculation. To prevent the lags from becoming cold bridges, the choice of lag material must be approached with appropriate knowledge.

Scheme beam ceiling, consisting of beams and internal filling.

Any floor structure must withstand prolonged fire exposure. Fire resistance limit various designs ranges from 15 to 50 minutes. Reinforced concrete floors, in this sense - the most persistent, wooden - the weakest. Therefore, before using a wooden beam, it is necessary to impregnate the wood of the beam with an appropriate fire-resistant material or use plastering of the finished structure.

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Types of floors

According to the type of construction, two types of overlap are distinguished. The first type is beam. It consists of beams and internal filling. The second type is a beamless design. Beamless is made of homogeneous elements, such as deck slabs or deck panels.

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Beamed wooden floors

The frame of such an overlap is wooden beams (logs), which should be fixed at a uniform distance from each other. The calculation of this distance is made depending on the section of the beam and the width of the span between the supporting walls.

Experts have long made such a calculation. The distance between will tell the table:

Section (for a wooden beam) cm x cm	Floor span width3 m	Floor span width3.5 m	Floor span width4 m	Floor span width4, 5 m	Floor span width5 m
Beam 5 x 16	0.8 m	0.6 m	0.45 m	—	—
Beam 6 x 20	1.25 m	0.80 m	0.70 m	0.55 m	0.45 m
Beam 10 x10	0.60 m	0.45 m	0.35 m	—	—
Beam 14 x 18	—	—	—	1,8	1,48
Beam 15 x 20	—	—	—	2,4	2,0
Beam 16 x 22	—	—	—	—	2,5

Wooden beam structures are perfect for building a private country house.

Unfortunately, these are not all the disadvantages of a floor using metal structural materials. Other disadvantages of such an overlap include:

Rust formation in damp rooms.
The need for lifting mechanisms during installation.
Good sound and thermal conductivity (these disadvantages are combated by wrapping the ends metal structures felt).

Rolling on such beams is not only from boards, but also from slabs. It can be lightweight reinforced concrete slabs or slabs from other lightweight and durable building materials- their application regulates the calculation.

To avoid corrosion bearing beams, use reinforced concrete beams overlap. Such beams are laid at a distance of 0.6 -1.0 m. The space between the beams is filled with lightweight concrete slabs or lightweight concrete blocks. On top of such an overlap, a screed is made under the floor, and the ceiling is plastered for whitewashing, painting or wallpaper.

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Beamless floors

Perform, at the same time, both the carrier and the enclosing (separating) functions. There are no beam crossbars in their design, and they consist of a monolithic slab or several slabs or panels. There are three types of beamless floors:

Prefabricated.
Monolithic.
Prefabricated monolithic.

Prefabricated ceilings cannot be assembled by hand, as this requires a lifting mechanism and slingers. But such an overlap is quickly assembled and withstands heavy loads. It is assembled from hollow or U-shaped reinforced concrete slabs. For installation of coatings logs made of wood can be used.

With their own hands, most often, they make. It can be done slowly and slowly. The most time-consuming and responsible stage in its implementation is the installation of suspended formwork and reinforcement. Pouring a concrete layer of 8 - 12 cm, compared to these painstaking work seems like a vacation. Do-it-yourself concrete of the M200 brand is poured, any reinforcement is used.

To lay the floor on such a structure, it is desirable to lay wooden logs. For linoleum flooring or tiles, logs do not need to be laid.

Thanks to the lags, you can make a perfectly flat floor in any room Modern technologies in construction, these are unique opportunities. For many, such words as bridging and polymers, tape floor, GOST, cabinets, column connections, dimensions 100x200, or 150x50 do not say anything. But those who have already encountered the repair know that we are talking, most likely, about the field on the logs. Someone just wants to reinforce the floor, while someone needs to lay a new, durable and beautiful one. And very often the technology of arranging the floor on the logs is used.

Their advantages: what are lags

It’s worth saying right away that laying the floor on the logs is in many cases simple perfect solution. Indeed, this method has many advantages. It is very important that the floor is warm.

Among the advantages of the lag, it is worth noting the reliability and low price.

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

Noise from neighbors in the apartment below will not penetrate to you;
Installation can be completely done by hand;
The cost of the floor 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 cheers up and sets you up for work.

Lags are called bars, which 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 to be laid. Wood is easier to work with and cheaper.

Logs differ from beams in mobility and smaller sizes. Beams after installation, to give a figurative example, cannot be moved, but logs can. Yes, and it is much easier to mount them, and if repairs are needed, it will be simple and quick.

Installation tools: laying floors on logs in the house

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

Everything necessary tools for mounting a log can be purchased at any hardware store at an affordable price

To prepare the floor for installation, the entire floor area should be freed. Check old coupler if the concrete floor is already deprived 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 of the subfloor. The floor should be primed. No matter how much the pros say about the need for a primer, there is some kind of careless attitude towards this procedure. The primer is right, it must be absorbed and dry, and only then the flaws are filled.

Then, the maximum point of the surface in the room is calculated from the level. You need to set a mark so that this is a guide 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 set the logs to the level with small plywood spacers.

Step-by-step instructions: do-it-yourself installation of a floor lag

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

To make the floor warm, heat-insulating material should be placed between the lags.

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

Modern logs for the floor: the size of the timber

The reliability of the design 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 beam is determined. Length is the length and width of the house. In this case, it is imperative to leave a gap, and the beam, respectively, 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 beam, its size is more difficult to calculate. Here, the potential load on the floor is important, as well as the size of the spans between the support points of these lags. There is a table that makes the calculations easier. The larger the span, the thicker the beam will be. For example, the span size is 3m, which means that the lag section is 150 by 80 mm. The sectional shape is usually rectangular. Install the beam on the edge so that the logs can withstand high pressure.

What is the distance between the floor joists

The lag step will depend on the thickness of the flooring. If you use flooring from durable thick boards, logs can be fixed relatively rarely. Well, subtle and not special durable coating requires more lag.

The distance between the lags should be chosen depending on the area of \u200b\u200bthe room and its design features

Dependence can be seen in 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, a step between lags of 700 mm.

You really don't need an exact calculation. It will be sufficient to take just the distance between our lags of the average value. And if at the end of the installation you saw that the distance was inaccurate, then make the step between these last lags smaller, and the structure will be strong.

Beam size: floor joists

The length of the beam should be approximately 3 cm less than the width and length of the room where the floor is laid. The length of the log must necessarily be less than the length of the room in order to avoid deformation of the structure if temperature changes 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 should be supporting elements, for example, pillars;
If adjacent logs are spliced, then the splicing points are positioned relative to each other with an offset.

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

Algorithm: laying the floor on the logs with your own hands

Lay wooden log needed 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 lag should be 1 cm (to avoid wood deformation). Then a number of logs are laid offset relative to the first log, by about a few 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 the reliability of fastening. Boards are attached along the wall, fixed with screws. The screws can be on the surface, it doesn't matter, the skirting boards will close them.

Hint: how to increase sexual lags

Everything is individual here, but some general rules eat. For example, if the sex lags and the strapping are on the same level lower bar, then you can fasten them together with forged brackets, or perforated corners will help. If the logs are located below the strapping beam, then a metal bracket is used.

Roughly speaking, the main objective reinforcements - rigid fixation of the floor log and beams lower crown. In this case, when strengthening the floor, the floorboards will stop moving apart. Still, as an option, you can rally the floors until the cracks are eliminated, and the gaps are simply covered with skirting boards.