There are two options for arranging wooden floors: along beams and along logs. The choice of one or another method of performing work depends on the individual characteristics of the room and the preferences of its owners. Among the advantages of floors made on beams, it should be noted high level their strength and low cost of work. Let's look at how to build floors on wooden beams below.
Floor construction on wooden beams: performing calculations
The use of wooden beams, compared to reinforced concrete ones, is distinguished primarily by their more affordable cost and ease of work. In addition, the floor has almost the same strength characteristics. The use of wooden structures helps reduce total weight house and its load on the foundation base.
Among the advantages of floor beams in a wooden house, we note:
- high resistance and rigidity to loads;
- light weight compared to concrete beams;
- affordable price;
- opportunity self-installation, without specialized technical equipment.
To install a floor on wooden beams, you do not need specialized equipment, since a few people are enough to lay the beams. The main load-bearing element of the structure is a wooden beam. She has a shape wooden beam, the height of which ranges from ten to thirty centimeters, and the thickness from seven to twenty centimeters. The optimal pitch for laying beams ranges from 65-100 cm. To determine the section of the beam, the individual characteristics of the room, the load and weight of the building, the span length and other important factors should be taken into account. Wooden boards connected to each other and mounted on an edge will help replace the timber. The use of hewn logs will be the most economical option for arranging the floor.
In order to determine the cross-section of a beam installed in a particular house, you must first determine the level of load that acts on it. To determine the total load, the weight of the floor, the load from people and fittings that will be installed on it are taken into account. General value the total load is four hundred kilograms per square meter. In relation to this value, the section and size of the beam is determined from the table:
If the span is about 4 m, then with an installation step of 65 cm, a beam measuring 10x20 cm will be required. Please note that the length of the beam must be 15 cm longer on each side to ensure its installation in the wall. That is, to determine the length of the beam, add 30 cm to 400 cm, you get 4.3 m.
Correct calculation of wooden beams allows you to select the optimal size of materials that will help correctly distribute the load in the building.
Laying of wooden beams is carried out in a direction parallel to each other. At the same time, the interval between the beams must be maintained in almost all areas, with the exception of chimney pipes and other structural elements ceilings The interval for laying beams in a house made of wood is about one meter. If the house is made according to frame technology, then this distance is reduced to 50 cm. If given value increases in relation to design features building, then between the beams it is installed additional element, improving their load-bearing capabilities.
If in the area close to the staircase opening there is no place for attaching the beam, an additional structure in the form of a wooden crossbar should be installed here. This will become the place to install the beams. At the same time, beams can be installed directly on or into the crossbar. In order for beams to easily withstand the loads placed on them, the following requirements must be met:
- the optimal height of the beams will be at least one twenty-fourth of its length;
- the width of the beam should be at least half its height;
- if the beam is installed in the attic, then a width of one third of its height is sufficient.
Using this relationship, it is possible to select best option beams for arranging floors. If the installation of beams is carried out in a section of fastening grooves, then the size of the beams should increase slightly. In order to reduce the thickness of the beam, if the floor is quite long, support pillars are installed between them.
If the installation of beams is carried out in outbuildings, garages, change houses or other non-residential premises, the level medium load decreases and ranges from 100 to 300 kg per square meter. At the same time, the cross-section of the beams should also be reduced.
If you could not find the specified size of beams, then the option of constructing them yourself using ordinary boards is possible. At the same time, they are laid in a checkerboard pattern, connecting to each other using nails.
During the further construction of the stove and chimney in the house, one should take into account the fact that the distance between it and the beam should not be less than thirty centimeters.
Floor covering with wooden beams: features of installation of beams
The wooden beams are fixed directly to the wall. If the ceiling is installed in the attic, then the beams are installed on the last crown of the wall, made of timber or logs.
A hole should be made in the wall, comparable in size to the beam. Before installation, the beam should be covered with tow. If there are beams that are too thin, they are installed 10-15 cm into the wall. In this case, a special cutting method is used. It is possible to attach the beam using a connection called a dovetail.
This option is suitable for houses that are also made of timber. To fix the beam in a house made of wood, a trapezoidal connection is used, and a clamp is installed for additional strength. In this case, the crossbar and the beam will be on the same level. The most in a simple way Installing floor beams involves installing cranial bars and fixing the beams on them. IN in this case, the size of the bars will be about 5x5 cm.
If the house is made of panels, then to lay the beam you should make a hole in the wall in the form of a nest. Each end of the beam is installed inside the holes. In this case, each beam socket must be at the same level. The optimal depth of the nest is about 15-20 cm, and the width between the beam and the wall is about 1 cm. Each of the ends that is installed in the nest is lined with tow. Next comes the process of treating the beam with an antiseptic solution. Thus, it will be possible to extend its service life and protect the coating from mold and mildew.
It is possible to fix the tow using steel anchors. One end of the anchor is installed in the socket, and the second is fixed on the beam with screws, while the length of the beam is calculated so that it does not fit into the wall and is equal to the length of the floor.
If the house is made of brick, then the installation of wooden beams will also require the construction of nests. They are supporting elements for holding beams. Try to build the nests as level as possible. In order to install the beams at the same level, you will need to level the bottom of the nests using concrete mortar. After the concrete solution has completely dried, roofing felt or roofing felt is installed on its surface to protect the wood from moisture.
In this case, the size of the nest is 6-10 cm larger than the thickness of the beam. The gap between the wall and the wooden beam should be about three centimeters. The depth of the nest is about 20-25 cm, but the beam is installed inside only 15 cm. The areas of wooden beams that are placed in the nest should be coated with hot bitumen.
Next, they are wrapped with roofing felt or glassine in two layers. After this, the rest of the beam is covered with a solution with antiseptic properties. After laying the beams in the nests, they should be filled with concrete mortar, for which crushed stone is used as a filler. The beams are aligned flush with the wall.
Flooring with wooden beams: features of floor construction
The rolling part of the floor is the ceiling on the rolling floor. There are several ways to lay out flooring. Most often, cranial bars are installed on the beam, the cross-section of which is 4x4 or 5x5 cm. The cranial bars are installed in such a way that they are flush with the beam. Next, a wooden roll is laid on the surface of the bars in the form wooden planks, the thickness of which is from 10 to 20 cm. At the same time, there should be no gaps between the boards. Will help replace boards ready shield made of wood or regular plywood. In order to arrange a flat ceiling on the lower floor, install on top of the roll plasterboard sheets or plywood.
Using another method of installing the roll-up, it is possible to significantly increase the ceiling area, if it is not large enough. Bars with a cross-section of 4x4 cm are installed on a wooden beam. The roll is laid on them, and its installation is carried out perpendicular to the beams. Next comes the installation of the filing in the form of boards, the thickness of which is the same as that of the previously installed bars.
In addition, to make the knurling, a beam is also used, the thickness of which is from 6 cm. Skull bars, the cross-section of which is 4x4 or 5x5 cm, are installed on the beam. Next follows the process of laying the beam. In this case, they are connected using the quarter method using a cut groove in the beam . The thickness of the beam depends on the height of the beams; they should be located at the same level. In this case, the beam performs the function of both rolling and filing. In addition, making a fastening groove inside the beam will help replace the cranial bars. In some cases, the bottom of the beams is left exposed and unfinished. This method relevant when used in a country style room.
Installing a floor on wooden beams: technology for performing the work
Next comes the process of arranging the floor on wooden beams. To begin with, bars are installed on each of the beams, in relation to which the surface of the flooring is formed. This stage involves adjusting the floor and constructing rough coating. Therefore, it is allowed to use unplaned boards, however, it must be covered protective materials and impregnations.
Next comes the work of waterproofing the decking. The best option is to use a clay-sand mortar that has the consistency of putty. Another option for performing waterproofing work is to use roofing felt. With its help, it is possible to provide high-quality waterproofing that does not take up much space. After this, the process of providing thermal insulation follows. The most popular materials for carrying out this work are the use of:
- slag poured between the beams;
- mineral wool;
- polystyrene foam;
- non-polystyrene;
- sawdust or expanded clay.
The most popular insulation for floors on wooden beams is mineral wool. It has high thermal insulation abilities, has long term operation, resistant to rodents and quite antiseptic.
Mineral wool is installed in such a way that it fits tightly to the floor surface. After this, a vapor barrier is installed, since this material is not resistant to moisture, which can reach it through a wooden floor.
Further actions are related to the arrangement of the finishing flooring. It is possible to install it directly on beams, but it is best to pre-install the system from logs. Thus, firstly, additional space and ventilation will be provided under the flooring, and secondly, the noise level emitted by the wooden floor will be significantly reduced.
In addition, it is possible to construct a floating wooden floor. Warm floors on wooden beams are distinguished by the presence of rigid fixation to the surface of the walls. In addition, it has excellent soundproofing characteristics and a low level of squeaking. As a final finishing material for arranging a concrete floor on wooden beams, planed batten, chipboard, laminate, parquet board or linoleum.
The possibility of unsupported covering of large areas significantly expands the architectural possibilities when designing a house. A positive solution to the beam issue allows you to “play” with the volume of rooms, install panoramic windows, build large halls. But if it is not difficult to cover a distance of 3-4 meters with “wood”, then which beams to use on a span of 5 m or more is already a difficult question.
Wooden floor beams - dimensions and loads
Made a wooden floor in timber house, and the floor shakes, bends, a “trampoline” effect appears; we want to make wooden floor beams 7 meters long; you need to cover a room 6.8 meters long so as not to rest the logs on intermediate supports; what should be the floor beam for a span of 6 meters, a house made of timber; what to do if you want to make an open plan - such questions are often asked by forum users.
Maxinova User FORUMHOUSE
My house is about 10x10 meters. I “threw” wooden logs onto the ceiling, their length is 5 meters, cross-section is 200x50. The distance between the joists is 60 cm. During the operation of the floor, it turned out that when children run around in one room and you stand in another, there is quite a strong vibration along the floor.
And such a case is far from the only one.
Elena555 User FORUMHOUSE
I can't figure out which beams are for interfloor ceilings needed. I have a house 12x12 meters, 2 floors. The first floor is made of aerated concrete, the second floor is an attic, wooden, covered with timber 6000x150x200mm, laid every 80 cm. The logs are laid on an I-beam, which rests on a pillar installed in the middle of the first floor. When I walk on the second floor, I feel shaking.
Beams for long spans must withstand heavy loads, therefore, in order to build a strong and reliable wooden floor with a large span, they must be carefully calculated. First of all, you need to understand what load it can withstand. wooden joist one section or another. And then think about, having determined the load for the floor beam, what rough and finishing floor coverings will need to be made; what the ceiling will be hemmed with; whether the floor will be a full-fledged residential space or a non-residential attic above the garage.
Leo060147 User FORUMHOUSE
- The load from the own weight of all structural elements of the floor. This includes the weight of beams, insulation, fasteners, flooring, ceiling, etc.
- Operating load. The operating load can be permanent or temporary.
When calculating the operating load, the mass of people, furniture, household appliances etc. The load temporarily increases when guests arrive, noisy celebrations, or furniture is rearranged if it is moved away from the walls to the center of the room.
Therefore, when calculating the operating load, it is necessary to think through everything - right down to what kind of furniture you plan to install, and whether there is a likelihood of future installation sports equipment, which also weighs more than one kilogram.
The following values are taken for the load acting on long wooden floor beams (for attic and interfloor floors):
- Attic floor – 150 kg/sq.m. Where (according to SNiP 2.01.07-85), taking into account the safety factor, 50 kg/sq.m is the load from the floor’s own weight, and 100 kg/sq.m is the standard load.
If you plan to store things, materials and other household items in the attic, then the load is assumed to be 250 kg/sq.m.
- For interfloor slabs and slabs attic floor the total load is taken at the rate of 350-400 kg/sq.m.
Flooring with boards 200 by 50 and other common sizes
These are the types of beams on a span of 4 meters that are allowed by the standards.
Most often, in the construction of wooden floors, boards and timber of the so-called running sizes are used: 50x150, 50x200, 100x150, etc. Such beams meet the standards ( after calculation), if you plan to cover the opening no more than four meters.
For floors 6 or more meters long, the dimensions 50x150, 50x200, 100x150 are no longer suitable.
Wooden beam over 6 meters: subtleties
A beam for a span of 6 meters or more should not be made of timber and boards of standard sizes.
You should remember the rule: the strength and rigidity of the floor depend to a greater extent on the height of the beam and to a lesser extent on its width.
A distributed and concentrated load acts on the floor beam. Therefore, wooden beams for large spans are not designed “end-to-end”, but with a margin of strength and permissible deflection. This ensures normal and safe operation of the ceiling.
50x200 - overlap for openings of 4 and 5 meters.
To calculate the load that the ceiling will withstand, you must have the appropriate knowledge. In order not to delve into the strength of strength formulas (and when building a garage this is definitely redundant), an ordinary developer just needs to use online calculators for calculating wooden single-span beams.
Leo060147 User FORUMHOUSE
A self-builder is most often not a professional designer. All he wants to know is what beams need to be mounted in the ceiling so that it meets the basic requirements for strength and reliability. This is what online calculators allow you to calculate.
These calculators are easy to use. To make calculations of the required values, it is enough to enter the dimensions of the logs and the length of the span that they must cover.
Also, to simplify the task, you can use ready-made tables presented by the guru of our forum with the nickname Roracotta.
Roracotta User FORUMHOUSE
I spent several evenings to make tables that would be understandable even to a novice builder:
Table 1. It presents data that answers minimum requirements by load for the floors of the second floor - 147 kg/sq.m.
Note: since the tables are based on American standards, and the sizes of lumber overseas are somewhat different from the sections accepted in our country, you need to use the column highlighted in yellow in the calculations.
Table 2. Here is data on the average load for the floors of the first and second floors - 293 kg/sq.m.
Table 3. Here is the data for the calculated increased load of 365 kg/sq.m.
How to calculate the distance between I-beams
If you carefully read the tables presented above, it becomes clear that with an increase in the span length, first of all, it is necessary to increase the height of the log, and not its width.
Leo060147 User FORUMHOUSE
You can change the rigidity and strength of the lag upward by increasing its height and making “shelves”. That is, a wooden I-beam is made.
Self-production of laminated wood beams
One solution for spanning long spans is to use wooden beams in the floors. Let's consider a span of 6 meters - which beams can withstand a larger load.
According to the type of cross section, a long beam can be:
- rectangular;
- I-beam;
- box-shaped
There is no consensus among self-builders as to which section is better. If we do not take into account purchased products (factory-made I-beams), then the ease of manufacture in “ field conditions", without the use of expensive equipment and accessories.
Just Grandfather User FORUMHOUSE
If you look at a cross section of any metal I-beam, you can see that from 85% to 90% of the metal mass is concentrated in the “shelves”. The connecting wall contains no more than 10-15% of the metal. This is done based on calculation.
Which board to use for beams
According to the strength of strength: the larger the cross-section of the “shelves” and the farther they are spaced apart in height, the greater the loads the I-beam will withstand. For a self-builder, the optimal I-beam manufacturing technology is a simple box-shaped structure, where the upper and lower “shelves” are made of boards laid flat. (50x150mm, and the side walls are made of plywood with a thickness of 8-12 mm and a height of 350 to 400 mm (determined by calculation), etc.).
Plywood is nailed to the shelves or screwed with self-tapping screws (not black ones, they do not work for cutting) and must be placed on glue.
If you install such an I-beam on a six-meter span with a step of 60 cm, then it will withstand a large load. Additionally, an I-beam for a 6-meter ceiling can be lined with insulation.
Also, using a similar principle, you can connect two long boards, collecting them in a “package”, and then put them on top of each other on an edge (take boards 150x50 or 200x50), as a result, the cross-section of the beam will be 300x100 or 400x100 mm. The boards are placed on glue and tied together with pins or placed on wood grouse/dowels. You can also screw or nail plywood to the side surfaces of such a beam, having previously lubricated it with glue.
Also interesting is the experience of a forum member under the nickname Taras174, who decided to independently make a glued I-beam to span a span of 8 meters.
To do this, the forum member purchased 12 mm thick OSB sheets and cut them lengthwise into five equal parts. Then I bought a board 150x50 mm, 8 meters long. Freza " dovetail“I chose a groove 12 mm deep and 14 mm wide in the middle of the board - so that it turns out to be a trapezoid with an expansion downwards. OSB in grooves Taras174 glued it in using polyester resin (epoxy), having previously “shot” a strip of fiberglass 5 mm wide to the end of the slab with a stapler. This, according to the forum member, would strengthen the structure. To speed up drying, the glued area was heated with a heater.
Taras174 User FORUMHOUSE
On the first beam I practiced “pushing my hand.” The second one was done in 1 working day. In terms of cost, taking into account all materials, I include a solid board of 8 meters, the cost of the beam is 2000 rubles. for 1 piece
Despite the positive experience, such “squatter construction” did not escape several critical remarks expressed by our experts. Namely.
When planning the construction of a country cottage, the owner has to solve the difficult issue of choosing floors. Some contractors advise him to use reinforced concrete panels, others insist on using wooden beams as a floor.
We decided to help newbies get out of a difficult situation. In our article you will find an overview of the advantages and disadvantages of wooden interfloor floors.
Useful tips for installing them and important nuances doing this work will also not be superfluous. We hope that the information received will be useful to you at the construction site and will help you avoid serious mistakes.
There is a stereotype in the minds of citizens according to which prefabricated reinforced concrete panels are the only Possible Solution for any building. It is not difficult to overcome it.
It is enough to list the advantages of wooden beam floors:
- Minimum cost (1 m3 of timber is several times cheaper than 1 m3 of hollow-core panels);
- The load on the walls is 2-3 times less than from the panels. This allows you to significantly reduce the consumption of reinforcement and concrete when constructing the foundation;
- On short spans (up to 4 meters), wooden beams can be laid manually using simple devices (a winch or a lifting block). Installing heavy slabs without a powerful crane is an unrealistic task;
- Low labor intensity and high speed of work (compared to pouring a monolithic reinforced concrete floor);
- Environmental friendliness (granite gravel is used in concrete, the background radiation of which can significantly exceed the norm).
As you know, there are no advantages without disadvantages. Wood floors have few of them:
- Increased deformability. It manifests itself in the effect of vibration when walking and the formation of cracks at the junction of plasterboard partitions;
- Low fire resistance (without special impregnation);
- Relatively short length (does not exceed 6 meters). For reinforced concrete panels it reaches 7.2 meters.
Among the disadvantages of these structures, some authors of feature articles include the formation of cracks in the ceiling plaster and poor insulation of impact noise. However, with a competent approach to installation, these two problems can be solved simply and reliably. For this below load-bearing beams lay a series of less thick beams, specially designed for lining the ceiling (plasterboard, OSB, lining, board).
The backing beam, like the main one, is placed on the wall, but lower, and the ceiling lining is attached to it. This solution is not found often, although it is competent and its history goes back more than one century; in addition to cutting off structural noise from the second floor, this option eliminates cracks in the ceiling. They appear when a beam serves as a support for the floor of the second floor and at the same time the ceiling of the first floor is attached to it. Vibration and shock loads cause cracks in the finish.
Areas of application and calculation of wooden floors
- in buildings constructed of wood (frame and log);
- V country houses, designed for summer operation;
- in outbuildings (sheds, bathhouses, workshops);
- V prefabricated houses collapsible type.
In addition to the listed options, wooden structures for interfloor ceilings can be used in cottages intended for year-round residence. Only in this case you need to use the two-row beam installation system, which we described above.
We do not recommend selecting the section of timber according to the principle “the thicker the better”. There is a simple calculation method taken from building regulations.
According to it, the height of the wooden beam must be at least 1/25 of the size of the span being covered. For example, with a 4-meter distance between the walls, you need to buy a saw log with a section height (H) of no less than 400/25 = 16 cm with a thickness (S) of 12 cm. To create a safety margin, the found parameters can be increased by 2-3 cm .
The second parameter that needs to be selected correctly is the number of beams. It depends on their pitch (the distance between the central axes). Knowing the section of the beam and the size of the span, the step is determined from the table.
Table. Choosing beam spacing
The design load of 350-400 kg/m2 indicated in the table is the maximum for the second floor. If it is not residential, then its value will not exceed 250 kg/m2.
When planning the layout of the beams, you need to take into account that the two outer ones must deviate from the end walls by at least 5 cm. The remaining beams are distributed evenly across the walls (in accordance with the selected pitch).
Installation stages and features
Technologically, the installation of floors using wooden beams cannot be called complex. The main attention should be paid to the horizontal alignment of the beams and the quality of embedding their ends into the wall mass. You cannot simply lay the beams on the masonry and cover them with bricks. It is necessary to provide them with a reliable connection with the walls and to properly protect the wood from rotting.
Options for sealing beams depending on the masonry material, type of wall structures (external, internal, chimney) and methods of their fastening are shown in the figures.
The length of the supporting part of the beams in a brick and block wall should be at least 16 cm (in a wooden wall 7-8 cm). If instead of timber, paired boards placed on edge are used, then they are embedded in the masonry at least 10 cm deep.
The side parts of the beams in contact with the wall are wrapped with 2 layers of glassine or 1 layer of roofing felt. Experienced craftsmen cut the ends of the beams at an angle (60-70°) and leave them uninsulated, not forgetting to treat them with an antiseptic compound evenly with the rest of the part. This ensures the “breathing” of wood wrapped in waterproofing.
When installing the ceiling, small gaps (3-5 cm) are left on the sides of each beam, filled with mineral wool or tow. A heat insulator is also placed in the space between the end of each beam and the wall. This eliminates the “cold bridge” that occurs by reducing the thickness of the masonry.
When installing floors in walls made of aerated concrete and arbolite blocks, it is recommended to use an open seal. In this case, the ends of the beams are also cut at an angle, antiseptic and covered with roofing felt and mastic, leaving the ends free.
The outer wall of the nest is insulated with felt or mineral wool and a box made from pieces of antiseptic board is inserted into it. Its height is chosen such that an air gap (2-3 cm) is formed above the beam. Through it, water vapor accumulating in the wood will escape into the room in the baseboard area. This solution protects the supporting part of the beam from rotting.
In practice, developers most often use a simpler method of sealing without the use of insulation and wooden box, covering the logs with block cuttings or just a raster.
The floor beams rest on, which is used to increase the spatial rigidity of the block masonry.
Beams are embedded in the internal load-bearing walls in a closed way. To increase the rigidity of the floor, they are connected through three to each other with steel anchor plates.
The section of the beam adjacent to the smoke duct is insulated with asbestos or other non-combustible material. The main protection against fire here is a brick cut (thickening of the pipe masonry) 25 cm thick.
In wooden houses, installation of beam floors is carried out in two ways:
- Cutting into log crowns;
- Through a steel shaped plate (chair), fixed to the wall using threaded rods.
Installation of ceilings by cutting into walls
Option to install beams on “chairs”
If top floor or the attic space will not be residential (heated), then it is necessary to insulate the wooden floors. To do this, insulation (mineral wool, ecowool) is placed in the space between the beams, having previously spread a layer of vapor barrier along the ceiling lining.
Polystyrene foam should not be used for this work for three reasons:
- It does not allow water vapor to pass through, and the wood underneath it rots;
- Does not isolate impact noise;
- It is problematic from an environmental point of view.
The design of the insulated floor is shown in the diagram.
The insulation of the ceiling of the first (ground) floor is carried out in the same way. The difference between them is that it is quite difficult to hem beams from below from a shallow underground. In this case, builders act differently. They tack a cranial block (5x5 cm) to the side edges of the beams. An antiseptic boardwalk is laid on it. It serves as a support for slab insulation, placed in the spaces between the bars. A vapor barrier is placed under the mineral wool. A vapor barrier is also laid on top of the beams. After this, logs are attached to them and the finished floor is installed on them.
The mineral wool slab should be placed between the beams as tightly as possible to prevent the floor from blowing through. For better insulation, all insulation joints are treated with polyurethane foam.
Control of the horizontal installation of the beams is carried out using a bubble level laid on a flat, long board. For leveling, use scraps of boards protected with bitumen mastic. They are placed under the ends of the beams.
Vapor barrier sheets should be laid with an overlap of at least 10 cm and all joints should be taped with construction tape.
To reduce impact noise, before installing the second floor floor joists, soundproofing tape 5 mm thick is laid along the beams. A waterproofing film is placed under the joists only if the second-level room is residential. It will protect the insulation from water entering when washing the floor. The technology for its installation is similar to laying a vapor barrier.
The final stage of installing a wooden floor is the installation of a subfloor made of boards, plywood or OSB boards using self-tapping screws. After completing this work, lay a final covering of laminate, linoleum, parquet and carry out finishing ceiling.
Private low-rise construction V last years is becoming more and more popular.
Country houses and country houses built with their own hands are occupying 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 produce the entire range 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, care should be taken Special attention strength load-bearing 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 of residential buildings should be 50 dB.
To meet this requirement, it will be sufficient to cover the floor of the second floor under the finishing coating with 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 amount of material for the flooring, 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. We multiply the resulting footage (the total length of all beams) 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 margin of 10 - 15%, since during construction unforeseen overexpenditures of material 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 required quantity 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, hydro is always used during construction. insulating materials.
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, created on the basis of 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 angles, anchor bolts, etc. 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 everything necessary materials purchased, and all preparations are 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 spacing between beams is influenced by technical indicators 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 mortgages should be installed under the ends of the beams to level the horizontal level. Mortgage resistant material is used for mortgages. physical activity– metal plates, pieces of tiles, 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 load-bearing 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 their lower part is flush with the lower part of the beams.
Most often, the subfloor is made from inch boards To install the subfloor, take edged boards and are 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. Read more about rough field watch in this video:
Thermal insulation flooring
After installing the subfloors, compartments are formed between the beams, which, if necessary, can be filled with 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.
Overlapping between floors is necessary to isolate the building levels from each other. Today there are a large number of ways to accomplish this task. It is worth noting that the cost may vary depending on the material. Some of the most popular devices are made of wood and metal. Which flooring to choose is up to you. In our article we will look at the features of beam floors and the basic rules for their creation.
Features of material selection
The wooden floor is installed with a width of no more than 8 meters. For load-bearing elements, a beam type of timber is chosen, having sections from 5 by 15 to 14 by 24 cm. It is worth noting that debarked logs with a corresponding diameter can be used. The pitch between the beams ranges from 1 to 6 meters.
In the production of the material, only coniferous wood is used. The strength level of such logs is much higher than other types of wood. Before using the timber, it is necessary to dry it thoroughly in the air. Tapping the material with a hammer should produce a ringing sound. The length of the beam rests tightly in the nests of the brick or log frame, with optimal size. In addition to covering the floor with wooden beams, you can choose the following products:
- To complete the task, you can use cranial types of bars measuring 5 by 5 cm. Such elements are mounted to the lower surface of the beams on both sides, and then the ceiling of the first floor is hemmed to the upper level.
- The second floor floor board is used. Unplaned wood can also be used for such purposes.
- Planed tongue-and-groove boards are also ideal for construction work.
- Insulating materials. For wood, you can use a mineral board or special rolls, since the fibrous structure will enhance fire protection. Plus, this method will improve sound insulation.
- Waterproofing film, which is used to insulate and protect the material from moisture.
- A special antiseptic, bitumen mastic or roofing felt scraps are also suitable.
Attention! The material you choose can create different decorative solutions, especially when using coating for these purposes.
Overlapping device
How to strengthen wooden floor beams? We will talk about this further in our article. It is worth noting that the surface between the levels of the building must be strengthened. To do this, treatment must be carried out to increase thermal, sound and thermal insulation, as well as ensure that all standards are met for the optimal load-bearing capacity of the elements.
You can make floors between floors of a wooden building yourself and in about one day. Plus, for such buildings there is no need to lay a powerful foundation. The span can be 5 or 6 meters long. Also, one should not forget about significant shortcomings, for example such as:
- The design has a high level of fire risk;
- The material may rot;
- Additionally, the device needs to be strengthened, since load bearing capacity elements have poor adhesion.
Attention! The low strength of the material does not allow it to withstand, and therefore for beams shorter than 5 meters in length, reinforcement is required. If this indicator is 5, 6 or higher, then it can be mounted without additional fasteners.
Types and classification of floors
The ceiling for the first floor should be waterproofed. It must be installed in such a way that there is a layer for ventilation. This method will preserve the integrity of the structure for long period. For level 2 perform additional insulation not necessary - this will make it possible to uniformly maintain the temperature inside the building. In this situation, it is enough to isolate the structure from noise exposure. Today there are several types of overlap:
- Structures with metal beams or wooden trusses;
- Use wood as the main material.
The first type was used until the 2nd half of the 19th century. It is worth noting that they were used only if the span was large. This method can be observed in the structures of old types of buildings, for example, Stalin buildings. The second type of flooring is used in the construction of stone and brick buildings. It should be noted that the material is used during major repairs.
For laying floors between floors, a dry type of wood is most often used. It is worth noting that to obtain such material, the logs are dried for 1 - 2 years.
Attention! The best results are obtained when drying for a period of 3 years.
Most often, experts advise choosing coniferous trees, as they have best indicator strength. By the way, pine logs best withstand negative factors environment. The span and amount of material are calculated taking into account certain construction tricky skills. Next, we will look at the main ways to increase your ability to withstand the load:
- If the beams are laid side by side, then the sum of the load capacity of adjacent elements is combined. So, if one log can withstand 6 hundred kilograms, then two can withstand a pressure of 1200.
- The strength of the structural parts is increased fourfold by stacking the beams one on top of the other.
- Beams are calculated using this technology: the cross-sectional value is usually more than 4 parts of the length. Thus, if the thickness is 6 meters, then the length should be 24 cm.
Please note that optimally selected beams will help extend the service life of the structure, as well as increase its stability.
Basics of installation work
One of the main components of a timber beam structure is the selected material. Thus, it is recommended to use deciduous or conifers wood The ceiling is created from beams, rolls and floors and insulation. In the case of creating a building in the form of a rectangle, it is better to use masonry parallel to the smallest wall.
To avoid the appearance of deflections of beam elements, it is necessary to maintain a certain structure among themselves. It is worth noting that to complete this task, you should take into account the cross-section of the parts and the length of the span.
Attention! With a thickness of 3 cm, the distance must be maintained at a distance of 50 cm. By the way, this value does not depend on the cross-section of the beams.
Before proceeding with installation work, the material must be processed antiseptics. We lay the ends of the beams on the wall and wrap them with roofing felt. It is worth noting that the ends of the elements must be left free. When performing this work, maintain a gap of 3 cm.
Attention! You have some free space left, so you can seal it with polyurethane foam.
Further anchor bolts We attach the beams to the structure. We attach cranial bars measuring 5 by 5 cm to the side part, which will provide a roll. Then we screw the boards to the structure with self-tapping screws. We definitely need these steps if we plan to do the ceiling ourselves.
After fixing the roll, we proceed to insulation, which will protect the building from noise penetration, and for basement and basements It will also create thermal insulation. For such purposes in modern construction mineral wool, which circulates air well.
Attention! For insulation you can use polystyrene foam, sawdust, wood shavings and expanded clay.
So we got acquainted with the features of ceilings and methods of their installation.
