Types of interfloor ceilings: building a house correctly. Interfloor overlapping on wooden beams: calculation for prefabricated loads and allowable deflection

The tendency to increase the number of floors of private houses forces us to solve the problem associated with the construction of floors. The level of modern construction technologies allows you to not be tied to certain conditions, which are associated with the configuration and size of the premises of the house. This expands the possibilities for the implementation of plans and facilitates the work. Before you start building floors, you need to thoroughly understand how this is done. In this article we will describe in detail how and from what to make floors between floors.

Basic requirements for floors between floors

Overlapping is a structural element of a building that divides the building in a horizontal plane with the formation of floors, and also separates them from the attic and basement. The share of costs for the construction of this structure is about 20% of the construction estimate. Overlapping refers to critical structures, therefore, at the design stage, one should adhere to the basic requirements that apply to them:

1. Strength indicators should be at a level that allows you to withstand the load, which consists of its own weight and the mass of structural elements, objects and people. The strength of the overlap increases with a decrease in the level of its location.
2. The stiffness parameters are directly dependent on the strength and width of the structure. For wooden structures, bending is allowed within 0.5-0.7% of their width, for steel beams - 0.25%.
3. The ceiling must provide sufficient sound insulation, at which the noise level is within the limits sanitary norms. The improvement of this indicator is achieved by increasing the tightness of the joints.
4. The structure must have adequate thermal insulation. If it is located between rooms with a temperature difference of more than 10 degrees Celsius, it is required to implement additional heat conservation measures.
5. To achieve the required fire safety, the floor material must have a certain fire resistance. This concept refers to the degree of protection of premises from the effects of fire for a certain time.
6. The combination of weight and thickness of the structure should be optimal.

How are floors classified?

Depending on the level at which the floors are located, the requirements for them differ.

The cover is:

Interfloor ceilings: manufacturing options

In construction, there is a wide variety of solutions for organizing floors. They may be:

1. Beamless: prefabricated, monolithic and prefabricated-monolithic.
   
2. beamed: wooden, metal, reinforced concrete.
3. Wooden.
   Wooden floors

   This design is the most common in construction. country houses. This is due to the possibility of creating the overlap yourself. In addition, the material is affordable and has good sound and heat insulation properties.

4. Metallic.
   This flooring option is usually used in the organization of the basement and basement. Metal constructions have high reliability and long service life, as well as their dimensions are smaller with the same bearing capacity.
   Metal products do not have sufficient thermal insulation and are subject to corrosion. The structure can be constructed from channels or I-beams, which are laid at a distance of 500-1500 mm from each other. They are used to install reinforced concrete slabs of small sizes.
5. Reinforced concrete.
   The use of this option necessitates the use of lifting equipment, since the mass structural elements significant. In addition, the foundation is subjected to heavy loads, which should be taken into account when designing.
   Reinforced concrete floors

   The indicators of sound and heat insulation of the material are at an average level, reinforced concrete is difficult to process and has increased labor costs during installation.

6. Coffered, arched and hipped.
   Ceilings of caisson and tent types are a kind of ribbed panels. They are used in the construction of facilities with big sizes, with complex architectural forms. Such ceiling structures are not relevant in the construction of private houses, as well as arched ceilings.

Overlapping on wooden beams: features

The construction of interfloor floors made of wood has several advantages:

• the design is simple in execution, it can be done with my own hands. Installation does not take much time. The cost of work is significantly reduced, due to the absence of the need to use special equipment, and activities for lifting and moving material can be carried out with one or two assistants;
• availability of wood. Used to make beams conifers trees that are widespread;
• relatively low weight, which makes it possible to significantly reduce the mass of the structure as a whole. Thus, the cost of construction is reduced;
• ease of installation of sound insulation improves the comfort of living in the house;
• wooden structures have a lower cost, which in general gives significant cost savings;
• the speed of creating the floor is comparable to the installation of the floor with slabs and is carried out in a day. In this case, the crane is not needed.

To disadvantages wooden floors can be attributed:

• the existing length limitation (4.5 m) does not make it possible to construct ceilings over rooms with a greater length without additional support;
• high fire hazard of wood requires special processing of parts;
• the tree is exposed to a number of biological factors, which is prevented by appropriate processing;
• relatively low strength.

Monolithic flooring on corrugated board: what to look for

The difference between creating a ceiling on corrugated board and concrete is the fact that in the first case, special formwork is not required, and as a result they have a finished ceiling. In addition, the technology using corrugated board does not need to be finished or improved.

The profiled configuration of the material creates the necessary strength and rigidity of the floor, thereby reducing the need for reinforcement and concrete. This is possible due to the fact that the solution fills only the voids of the ribs, and does not occupy the entire surface of the sheet.

To create such an overlap, it is important to use only sheets intended for roofing.
The essence of the technology is the use of corrugated board as a formwork, which is not dismantled after pouring concrete. The resulting structure has as bearing supports special facility, consisting of metal columns, beams, lag. As a result, the load is redistributed from the ceiling to the supports, while the walls are not loaded. Such a constructive solution makes it possible to carry out lightweight walls.

In addition, the organization of the support system allows instead of expensive strip foundation use a glass type support. This will significantly reduce the construction cost.

Overlapping with slabs between the first and second floor: reinforced concrete

Slabs made of reinforced concrete are widely used. According to some parameters, when compared with the monolithic execution of the ceiling between the first and second floors, they have the best performance.

The organization of such an overlap requires a powerful foundation and involves the construction of walls from durable materials. As a rule, floor slabs are used for high-rise buildings.

Structures made of reinforced concrete slabs are reliable, durable and have a long service life. The magnitude of the loads that concrete can withstand is colossal. It is characterized by the property of increasing strength characteristics over time. In addition, the material fully meets the requirements for heat and sound insulation, and also have sufficient fire safety. The process of installing a ceiling from slabs does not require much time using special equipment and is not difficult.

The main disadvantages of reinforced concrete products include their significant mass and the need to use special equipment during the installation. In addition, such overlaps require the creation of a screed so that the load on them is uniform.

With all the shortcomings reinforced concrete slabs ceilings are successfully used in the construction of private houses.

Overlappings between floors in a private house are structures that divide the premises in height, forming floors. These structures separate the basement and attic from the main ones. They must have sufficient strength to withstand the load of their own weight and payload, which turns out to be furniture, people, as well as equipment.

general description

The amount of payload per square meter will depend on the purpose of the premises and the nature of the equipment. If it's about given value no more than 105 kilograms per square meter. For interfloor overlap, this value increases to 210 kilograms per square meter. The floors between floors in a private house must be strong, under the influence of loads they should not bend, the allowable bending value for attic floors is 1/200, while in the case of spans between floors this value should be 1/250.

Basic requirements for floors

During the construction of floors, a sufficient degree of sound insulation should be ensured, the value is set by the standards during the design. To do this, close the gaps at the joints of the material, only in this case, sounds from neighboring rooms will spread minimally. Ceilings that separate rooms with a certain temperature difference must comply with thermal protection requirements. This indicates the need for an additional layer of thermal insulation. Any structure, especially made of wood, is not able to withstand prolonged exposure to fire. It should be remembered that each material is characterized by a certain value of the fire resistance limit. For reinforced concrete floors, it is 60 minutes, but if the structure is made of wood with backfill, and has a plastered surface from below, then fire resistance will last 45 minutes. which are protected by a layer of plaster, are able to withstand the flame for about 15 minutes. If there are wooden floors that were not protected by fireproof materials during the arrangement, it should be borne in mind that their fire resistance limit is even less.

Types of floors

Overlappings between floors in a private house can be interfloor, basement, basement or attic. By constructive solution The bearing part of the floors can be beamed or beamless. In the first case, the system consists of beams and infill. In the second, the structure is made of homogeneous elements like panels or slabs.

Features of the beam ceiling

Overlappings between floors in a private house can be beamed, while individual elements are located at an equal distance from each other, and filling elements are laid on the beams. The latter act as a barrier. Beams can be metal, reinforced concrete or wood.

Features of the construction of floors from wooden beams

In the construction of private houses in most cases are used beam ceilings from wood. For beams, there are restrictions on the width of the span, they can be used for attic floors or interfloor structures, in which the span should be 5 meters. Such products are made of coniferous or hardwood, and on the upper side there is a flooring, which is the floor. The design of such an overlap provides for the presence of beams, rolling, floor and heat-insulating material.

If you decide to build floors between floors in a private house with your own hands based on wooden beams, then you should know that the house can have a rectangular plan. In this case, it is necessary to overlap the spans in the direction along the short wall. In order for the floor to not sag under its own weight, its elements are laid at a certain distance. If it is necessary to build a 3x4 meter ceiling, 6x20 beams should be used, which are laid along a 3 meter wall. If the ceiling is interfloor, then the beams should be 1.25 meters apart, in the case of an attic floor, the distance increases to 1.85 meters. This indicates that as the span increases, the distance between the beams becomes larger.

Work technology

If you will be laying floors between floors in a private house made of wood, then initially the elements are treated with an antiseptic. When they are supported on concrete or stone wall the ends are wrapped in two layers of roofing material, and the beam is inserted into the prepared nest. In this case, the element must not reach rear wall 3 centimeters, the end of the beam should be beveled. Remaining free space filled with thermal insulation, which can be replaced with mounting foam.

On the side faces of the beams, 4x4 or 5x5 bars are fixed, which are called cranial. On the bars is fixed reel from wooden shields. The roll plates are tightly pressed against each other, they are attached to with the help of self-tapping screws. When overlappings are performed between floors in a private house, it is recommended to consider the photo in advance. This will allow you to understand that the design provides for the need for laying insulation. It will play the role of a noise-absorbing layer, and in the attic floor - the function of thermal insulation. As a material, you can use foam, expanded clay, sawdust, mineral wool, shavings, straw, as well as tree foliage. After fixing the roll-on, thermal insulation is laid on top. Between the beams, you should first lay a layer of roofing, vapor barrier film or glassine, bending the material five centimeters onto the beams. Then comes the turn of laying a layer of thermal insulation.

Concrete floor construction

Concrete floors between floors in a private house may have different forms. If we are talking about monolithic structures, then they are a solid slab, the thickness of which is equal to the limit from 8 to 12 centimeters. In this case, concrete grade M 200 is used, the slab itself is supported by Mass square meter such an overlap can be 490 kilograms if the thickness is 200 millimeters. Installation is carried out in several stages, the first is the installation of load-bearing beams on a prepared site, then it is equipped wooden formwork from an unedged board, and at the next stage 6 mm reinforcement is laid. On the final stage concrete is being poured. The thickness of the floors between floors in a private house can be equal to the above limit, but it is also important to correctly build the formwork, which is sometimes purchased in ready-made. It consists of beams, plywood, and a tripod. If you use formwork made of aluminum or wooden beams, then the master will have the opportunity to build a ceiling of any configuration.

Conclusion

Ceilings between floors in a private house made of aerated concrete are usually equipped with wood, since the weight of the material at the base of the walls is not so large as to undergo concrete loads.

Interfloor overlappings are practically the same in terms of the constructive principle. Whether it is the ceiling of the basement in the garage or the ceiling of the last floor.

However, the device technology of each of them will be different, and performance will depend on the correct manufacture.

According to the constructive principle, overlapping devices are divided into 4 main types:

• monolithic reinforced concrete floors;
• slab ceilings made of prefabricated reinforced concrete;
• ceilings are often ribbed (prefabricated-monolithic);
• wooden ceilings.

Consider the two most common ways to organize floors - wooden and monolithic

Wood, unlike other bases (reinforced concrete slabs, monolith), used for floors, is environmentally pure material. Besides wooden ceiling or the floor gives the room a distinctive look and retains heat well. Previously, the tree was used for these purposes all the time. Now interfloor floors made of wood, as a rule, are made only in wooden houses, although there are exceptions.

When building a house, you often have to face the problem of choosing a type.

There are three main options for this work:

1. Installation of reinforced concrete slabs.
2. Application wooden structure separating two floors.

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The use of reinforced concrete slabs

Reinforced concrete slabs, with the help of which the floors in the house are covered, are structures made of iron and concrete. Inside the slabs there is a reinforcing crate and round voids that stretch along the entire length of the product. The main purpose of voids is to reduce its mass and increase the index of resistance to deformation to fracture.

Reinforced concrete slabs have different sizes both in length and width. You can find out their dimensions by the abbreviation. For example, PK 72.15-8 products mean that the length of the plates is 72 decimeters and the width is 15 dm. The number "8" shows the design load that the structure will withstand (800 kgf / m).

The minimum weight of reinforced concrete floor slabs exceeds 500 kg. All these data indicate that it is impossible to do it yourself. To carry out the work, we can not do without:

• reinforced concrete slabs;
• lifting crane;
• welding machine;
• spider devices;
• steel bars;
• crowbars;
• trowel;
• cement mortar.

Plates must necessarily have four mounting loops, which can be in the form of curved parts of reinforcement or free reinforcement placed in recesses near the corners of the product. By purchasing reinforced concrete structures, all hinges should be carefully inspected. They must be whole.

The technological process involves the application of cement mortar on the wall at. This method leads to a stronger fit of the elements of the first and second floors, and also prevents the occurrence of cracks at the points of contact of reinforced concrete structures with the wall. But at the same time, making a mortar and laying it on walls, piles, beams or pillars should be done at the time of preparing the slab for installation work. This will prevent it from premature hardening.

The next step in creating a floor between floors is to attach the "spider" device to the mounting loops of the reinforced concrete slab. Only using this device (equipped with hooks and four cables of the same length), you can get horizontal position plates without rotating. Floor overlapping is best done by three people: one person will manage crane, and two are in the place of implementation installation work and align the installed plates with crowbars.

Plane reinforced concrete product has the shape of a trapezoid. Her top part slightly narrower in size. When an overlap is created, and the slabs are laid next to each other, then at the junction a recess 5-7 cm wide is obtained. It is obtained by pouring concrete into it. The hinges on adjacent slabs are also connected. It happens in the following way. Steel bars are taken, inserted into the loops of adjacent plates and bent. Now reinforced concrete structures are firmly connected to each other.

Mandatory requirements for overlapping the first and second floors with slabs are:

• compliance with safety rules;
• overlap load-bearing structures carried out extreme points reinforced concrete slabs;
• installation of the structure should provide for a strip of more than 15 cm in size between the edge of the slab and the outer part of the wall (a place for laying bricks).

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Technology for creating a monolithic structure

The monolithic ceiling of the first floor is a more durable structure. This technology it is used in almost any house (brick, aerated concrete, foam concrete, cinder concrete, reinforced concrete blocks) and it can be done independently. Sometimes a monolithic floor is the most suitable option due to the fact that reinforced concrete slabs cannot be installed for objective reasons (the presence of power lines, there are no entrances to the facility under construction, etc.).

To do monolithic structure between floors, we need the following materials and tools:

• cement (grade 400 and above);
• sand;
• crushed stone;
• ruberoid;
• steel fittings (20-25 mm);
• mesh for reinforcement;
• beam, wooden planks, channel or metal pipes for supports;
• unsuitable formwork boards;
• concrete mixer;
• Master OK
• buckets;
• hammer;
• rope;
• nails.

Monolithic overlap involves the construction of formwork when the walls of the first floor are erected to the desired height. First, vertical supports are installed at a meter distance from each other. Their dimensions must correspond to the dimensions of the formwork boards, which must be adjacent to the walls. The number of supports depends on the area of ​​\u200b\u200bthe house on which it is planned to cover the first floor.

Particular attention should be paid to the soil, which should not sag under the mass of the monolithic floor. Boards are tightly laid on the supports in the transverse position, which will become the bottom when the concrete solution is poured. Formwork is also created along the perimeter of the floor. It is necessary to do the work in such a way that the monolithic ceiling, which "lies" on the walls, does not push through the formwork. Important point- this is a high-quality connection and fixation of corners.

There are several requirements for the arrangement of formwork for a monolithic slab. The main ones are:

1. To prevent the poured concrete from leaking, the boards are placed to each other at the shortest possible distance.
2. To create vertical supports, only the most durable boards are used, which will not bend under the weight of the monolith and transverse beams.
3. To fix the height of the monolithic slab, a gutter is created on the outer perimeter of the formwork.
4. After the concrete mortar has set, the formwork is dismantled. For this reason, formwork must be done in such a way that it does not lie on the walls.

After the erection of the formwork and a thorough check of the reliability of the structure, it is possible to start pouring the monolithic ceiling. At its bottom, which is lined with boards, it is covered with roofing material. Thanks to him, all the remaining gaps between the boards are closed. Then, at a height of 6-8 cm from the roofing material, reinforcement and reinforcing mesh are fastened.

Made from sand, cement, gravel and water concrete mortar poured into the formwork. The overlap between floors should be 10-15 cm thick. If it is smaller, then there is a danger that the overlap may not withstand the load. At big thickness walls will undergo a solid load. A month later, the formwork is dismantled, and work on the construction of the second floor continues.

For execution interfloor overlap in private housing construction, as a rule, one of four options is used:

Each of these methods has its own advantages and disadvantages. Let's look at each of them in more detail and try to choose the most suitable option for us.

Before I begin to express my opinion about each overlap option, I want to draw your attention to the fact that any of them is best performed on a reinforced belt. Firstly, a reinforced belt will give your building an additional margin of safety, and secondly, it will more evenly transfer the load from the ceiling to the walls.

It is carried out in buildings with walls made of almost any material, but I can say that this type of flooring is ideal for walls made of SIP panels. I can’t say that this method is less time-consuming than the others, rather the opposite. The meaning of this design is as follows: wooden beams with a section of 100x200mm are laid against the load-bearing walls, the beams are laid on the side with a length of 100mm, the distance between the beams is from 0.60m.

On many sites you can find the given calculations of floor loads, distance and section of beams which must be applied depending on the length of the span (distance between bearing walls). On this occasion, I would like to say only the following: Do not bother your head. All these troubles are drawn from SNiPs and GOSTs for construction, written back in the last century for standard construction. Think for yourself, most lumber is made 4.50m long, beam section 200x200mm, half-beam 200x100mm. Finding or ordering lumber with other parameters is quite difficult and costly. So why do you need it? Got extra money? Give money to your wife, she will find a worthy use for them ;-). It just so happens that it is better to think in advance about what material the floor will be made of and design the premises with the appropriate geometric parameters, so as not to run around the neighborhood later, in search of a beam 5.50 m long and 300x150 mm in section. Based on all of the above, we return to the essence of our question: we accept beams with a section of 200x100mm, a distance between them of 0.60m and finish the puzzle on this. It is advisable to use larch timber for overlapping, this type of wood resists decay very well compared to other types of wood.

After installation, they are attached to the beams cranial bars with a section of 40x50mm. They serve as a support for the reel shields. You can fasten the bars with both nails and screws, the main requirement is reliability. The bars must bear the weight of the roll-over boards and materials that act as soundproofing.

Next, roll-up shields are laid. The roll-up shield is boards made of low-grade wood, laid perpendicular to the beams on the cranial bars. In our case, it is quite possible to use substandard tess, its thickness is 20mm, width 180-250mm. Before laying, the boards for the roll-up shield must be antiseptic and treated with flame retardants. There should be a gap of 8-10 mm between the overrun shield and the floor beam. Between the boards of the roll-over shield itself, the gap should be minimal.

According to the roll-over shield, I advise you to lay polyethylene film in one layer with an overlap on floor beams. This is done so that the particles soundproofing material and the dust did not pour through the remaining cracks.

Then stacked soundproof material. Mineral wool can be used as such a material, sawdust is well suited from improvised means, less often polystyrene concrete slabs with a strength grade of D200 or less are used.

After the installation of sound insulation, a draft floor is laid from boards 40-50 mm thick, and a number of works are carried out on the installation of the finishing floor.

Prefabricated reinforced concrete floors

As well as in the case of the basement interfloor overlap, it has a very high labor intensity. Simply put, it will be quite difficult for you to make it yourself. This is due to the fact that the implementation of this requires the installation of formwork, a large number of supports, the implementation of a serious reinforcement cage and high-quality concrete mix. Based on the foregoing, I strongly recommend that you perform interfloor overlap on beams or slabs. If you have the opportunity to use metal I-beams, then it will be just gorgeous. But in the absence of a better one, I advise everyone else to accept leafy beams with a section of 200 x 100mm. This method is the most optimal in terms of price / quality.

Currently this species overlap is becoming quite popular. The design is such that it allows you to make overlap, both along the basement and between floors. The use of small hollow blocks allows you to make floors in buildings with a difficult geometric shape(use of bay windows and other architectural delights). The essence of this method is quite simple:

Hollow metal beams are laid

Hollow blocks are laid on the beams

The entire structure is filled with concrete.

At the same time, it is very important that the concrete has as much adhesion to the beams as possible. Well, everything seems to be simple. This type of flooring has a number of advantages over prefabricated and monolithic ceilings:

The construction process requires less labor (3-4 people)

the overlap is lighter (20% lighter than prefabricated, and 50% lighter than monolithic)

Significantly reduced cost (up to 30%)

Not required construction equipment(enough power tool)

No leveling screed required

Everything is pretty simple. As I deal with this type of overlap in more detail, I will immediately write a detailed article on this topic.