Floors made of precast reinforced concrete (floor slabs).
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Today, reinforced concrete slabs are the most commonly used type of interfloor slabs. According to their load-bearing capacity, they are divided into three main groups: Load-bearing capacity: 400 kg/m2 or 4 load Load-bearing capacity: 600 kg/m2 or 6 load Load-bearing capacity: 800 kg/m2 or 8 load Currently, slabs with load-bearing capacity are mainly produced capacity of 800 kg/m2, with very rare exceptions you can find 600 kg/m2 and not 400 kg/m2 at all. And at the same time, there is SNIP 2.01.07-85 “Loads and Impacts”, which determines the necessary and sufficient load-bearing capacity of floors depending on the type of premises. In accordance with SNIP (clause 3.11 table 3), the load-bearing capacity of the floors of an apartment in a residential building is 150 kg/m2, and the highest value is 500 kg/m2 and is reserved for book depositories, archives, stages of entertainment enterprises, stands for standing spectators, as well as for premises for raising cattle. Now let's figure out what a load-bearing capacity of 800 kg/m2 means in relation to the house in question. Let's take as an example the most loaded room, namely the Kitchen-Living Room (with an area of 27.3 m2). When using reinforced concrete slabs, the load-bearing capacity of this room will be: 27.3 m2 * 800 kg/m2 = 21,840 kg, if we subtract the weight of furniture and interior elements from this value (maximum 500 kg), we will get a residual load-bearing capacity of 21,340 kg. Now let's determine how many people can withstand such an overlap with an average person weighing 100 kg. Number of people = 21,340 kg / 100 kg = 213 people! It is clear that such a number of people simply cannot fit in this room. If we talk about the possibility of this room from the point of view of the people present, then this is no more than 20 people at “peak” load. In other words, you will get a safety factor of 10! In civil engineering, the safety factor does not exceed 0.5, and for military designers/builders it does not exceed 5! |
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In fact, by using reinforced concrete slabs, you get high load-bearing capacity, the value of which exceeds the standard by 5 times! In this case, under no circumstances will you use the high load-bearing capacity “for its intended purpose,” since there is not enough room area to place a significant load on it. From the point of view of fire safety, sound insulation, thermal insulation, the option of reinforced concrete slabs does not stand out in any way compared to other types of floors. It is based on the above that the load-bearing capacity standard for apartments in residential buildings is set at 150 kg/m2. If we carry out similar calculations, but in accordance with the standard value, we get: 27.3 m2 * 150 kg/m2 = 4,095 kg, if we subtract the weight of furniture and interior elements from this value (maximum 500 kg), we get the residual load-bearing capacity 3,595 kg. Now let's determine how many people can withstand such an overlap with an average person weighing 100 kg. Number of people = 3,595 kg / 100 kg = 36 people! It is clear that such a number of people simply cannot fit in this room. If we talk about the possibility of this room from the point of view of the people present, then this is no more than 20 people at “peak” load. In other words, you will get a safety factor of 1.8! Let me remind you that in civil engineering the safety factor does not exceed 0.5, and for military designers/builders it does not exceed 5! That is why the standard of 150 kg/m2 is sufficient for normal operation of residential premises! P.S. When designing lightweight, economical LVL timber floors, we set a load-bearing capacity of 180 kg/m2, thereby slightly exceeding the standard and obtaining a safety factor of at least 2! |
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Calculation of costs for installing precast reinforced concrete floors over a cold underground using floor slabs of the PNO series. The calculation also includes materials for thermal insulation and leveling the base for finishing the floor.
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1. PNO slab 1m2/ 1125 RUR 2. Mortar for joints M200 0.126tn / 315 rubles 3. Leveling screed M200 thickness 50mm 0.100tn / 250 rub. 4. Extruded foam 5. Vapor barrier film 1m2 / 22 rubles 6. Reinforcing mesh 200x200x5mm 1m2 / 60 rub. 7. Leveling screed M300 thickness 50mm 0.100tn / 260 rub. 8. Finishing screed 5mm 0.0075tn / 203 rub. Total cost of materials for 1m2 = 2,969 rubles |
1. Installation of PNO slabs 1m2 / 600 rubles 2. Concreting slab joints 1 piece / 288 RUR 3. Performing a leveling screed M200 thickness 50mm 1m2 / 400 RUR Total cost of work for 1m2 = 2,488 rubles |
Total materials and work for the installation of prefabricated reinforced concrete floors: 5 407-00 rub/m2.
Floors made of monolithic reinforced concrete.
Scope of application: Interfloor ceilings in construction.
We calculate the costs of erecting 1 m2 of floor structure.
Calculation of costs for installing a monolithic concrete floor over a cold underground. In addition to the material of the supporting structure, the calculation also includes materials for thermal insulation and leveling of the base for finishing the floor.
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1. Ready-mix concrete B 25 1m2/ 880 RUR 2. Reinforcement (12mm and 6mm) 0.02t / 500 rub. 3. Extruded foam listyrene, thickness 150mm 0.150m3 / 734 RUR 4. Vapor barrier film 1m2 / 22 rubles 5. Reinforcing mesh 200x200x5mm 1m2 / 60 rub. 6. Leveling screed M300 thickness 50mm 0.100tn / 260 rub. 7. Finishing screed 5mm 0.0075tn / 203 rub. 8. Rent of formwork for a month 1 unit / 400 rubles Total cost of materials for 1m2 = 3,059 rubles |
1. Installation / dismantling of formwork 1m2 / 600 rubles 2. Installation of arm. frame 0.02t / 200 rub 3. Laying concrete taking into account cost of a concrete pump 1m2 / 580 rubles 4. Laying extruded foam listyrene, thickness 150mm 1m2 / 100 RUR 5. Laying vapor barriers. films 1m2 / 100 RUR 6. Installation of reinforcing mesh 1m2 / 150 rubles 7. Performing a leveling screed M300 thickness 50mm 1m2 / 600 RUR 8. Performing finishing screed 1m2 / 200 rubles Total cost of work for 1m2 = 2,530 rubles |
Total materials and work for installing a monolithic floor: 5,589-00 rub/m2.
Floors on wooden beams.
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| Below is a calculation of the costs of installing a floor using classic edged lumber - wooden beams. The span between the supports is considered to be 4.7 meters. To costing materials for thermal insulation and leveling the base for finishing the floor are also included. The wooden elements of the rafter structure are made from coniferous wood with moisture content no more than 20%, pre-treated with protective compounds in accordance with the requirements SNiP 2.03.11-85 "Protection of building structures from corrosion", Chapter 3 "Wooden structures", as well as the requirements of SNiP 2.01.02-85 “Fire safety standards” clause 1.8. For a span of 4.7 meters, with a center-to-center distance of 500mm when using wooden beams 200*100 mm provides the following overlap indicators: Load-bearing capacity 300 kg/m2, Weight of floor structures 140 kg/m2 |
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We calculate the costs of erecting 1 m2 of floor structure.
Calculation of costs for installing a floor made of wooden beams over a cold underground. In addition to the material of the supporting structure, the calculation also includes materials for thermal insulation and leveling of the base for finishing the floor.
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1. Lumber 1.97 m3 / 15,760 rub. 2. Fasteners 1 piece / 3600 rub. 3. Fire and bioprotection 1 piece / 7800 rub. 4. DSP 20mm 39m2 / 13380 RUR 5. DSP 10mm 39m2 / 8350 RUR 6. URSA PureOne 200mm 7.8m3 / 11,270 RUR 7. Vapor barrier and tape 1 piece / 2000 rub. 8. Leveling screed M300 thickness 50mm 3.9t / 10140 rub 9. Finishing screed 5mm 0.29tn / 7920 RUR Total cost of materials for 39.25 m 2 = 80,220 rub. |
1. Installation of the floor frame 350 RUR / 13,650 RUR 2. Fire and bioprotection 200 rub / 7800 rub 3. Installation of 10mm DSP 200 RUR / 7800 RUR 4. Installation of 20mm DSP 200 RUR / 7800 RUR 5. Installation of PureOne insulation 200 RUR / 7800 RUR 6. Laying vapor barriers. films 100 rub / 3900 rub 7. Performing a leveling screed M300 thickness 50mm 600rub / 23400rub 8. Performing finishing screed 200 RUR / 7800 RUR Total cost of workfor 39.25 m 2 = 79,950 rub. |
Total materials and work for the installation of floors on wooden beams: 4 081-00 rub/m2.
Floors on beams made of LVL timber.Scope of application: Interfloor ceilings in construction, frame housing construction, rafter system.
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Below is a calculation of the costs of installing a floor using LVL timber. The span between the supports is considered to be 4.7 meters. The calculation also includes materials for thermal insulation and leveling the base for finishing the floor. Load bearing capacity 300 kg/m2 Weight of floor structures 55 kg/m2, the total “free” load-bearing capacity of the floor is 245 kg/m2 (according to SNiP “Loads and Impacts” for residential buildings the standard is 150 kg/m2). In the calculation presented below, the center-to-center distance between the beams is taken to be 625 mm to ensure waste-free laying of the 1,250 mm wide CBPB slab To simplify calculations, the following costs are given for a room of 8.3x4.7 m. |
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We calculate the costs of erecting 1 m2 of floor structure.
Calculation of costs for installing LVL beams over a cold underground. In addition to the material of the supporting structure, the calculation also includes materials for thermal insulation and leveling of the base for finishing the floor.
Total materials and work for the installation of floors on beams made of LVL timber: 2 942-00 rub / m 2.
What's in the bottom line?
Costs for erecting a floor structure for a house according to project 83-08.
Base area 124 m 2
Option 1. Floors made of precast reinforced concrete = 5,407 rub./m2 * 124m2 = RUB 670,468
Option 2. Floors made of monolithic reinforced concrete = 5,589 rub./m2 * 124m2 = RUB 693,036
Option 3. Floors on wooden beams = 4,081 rub./m2 * 124m2 = RUB 506,044
Option 4. Floors on beams made of LVL timber = 2,942 rub./m 2 * 124 m 2 = RUB 364,808!
It is worth noting:- glued beams do not create creaks
- in our projects, the ends of the beams are not embedded in the body of the wall, the beams are fastened on brackets, even capillary suction of moisture from the wall structure is eliminated, the floor materials always remain dry, as a result, the service life of the floor is equal to the service life of a stone house
- the space between the beams is completely filled with non-combustible mineral wool material, the subfloor, as well as the lining of the beams, is made using materials that do not support combustion: DSP, fire-resistant plasterboard, this design has high fire resistance ratings, because there is no free air around the beam necessary for the combustion process.
Today LVL timber has the best price/quality ratio. It is this material that is preferred in many private and public facilities, for example, the balconies of the Mariinsky Theater or the supporting frame of the dome of the new Oslo airport are made of LVL timber.
Additional benefits of choosing modern construction technologies.
The use of modern materials and solutions in construction, such as LVL timber for floors and rafter systems or porous ceramic blocks Cayman30 for external load-bearing walls, allows for savings not only within the framework of the current technical solution, without compromising the necessary and sufficient consumer properties and characteristics, but and significantly reduce costs at other stages, as well as obtain higher quality construction.
As an example, we can cite a situation where the replacement of reinforced concrete floors with floors using LVL of timber and 44 conventional ceramic blocks for thermally efficient ceramic blocks Cayman30, for external and internal walls, significantly reduces the weight of the house.
Difference within house project 83-08 is:
- on floors 147.8 tons
- along the walls 37.9 tons,
Replacing a monolithic strip foundation with a monolithic pile-grillage foundation will also lead to a general reduction in the load on the foundation, by approximately another 99 tons.
The total reduction in the weight of building structures, and as a consequence of the pressure on the foundation, is 284.7 tons.
When constructing various buildings and structures for both residential and industrial purposes, an important stage is the choice of material and the implementation of the floor. With the help of such structures, high-rise buildings are divided into floors. During the operation of a building, floors are subject to high loads, so it is important to choose the right material and install it correctly.
The main types of floors
Based on their purpose, structures are divided into three groups:
- attic: such structures separate the top floor and the attic space under the roof of the building. To create an usable attic area, it is recommended to use reinforced concrete slabs that can withstand a load of 400 kg/m2;
- interfloor: such floors are used to divide into separate floors. When choosing a material for their creation, the degree of load of interior partitions, interior items, various equipment, people, and so on is taken into account. Experts recommend using reinforced concrete slabs marked 6At and higher;
- basement: such structures separate the space of the lower level, which includes garages, basements and other rooms. The technical requirements for the material for these floors (degree of load, rigidity, strength) are similar to those for interfloor floors. Additionally, experts recommend insulating the structure and waterproofing it.
Based on the type of construction, floors are usually divided into the following categories:
- Full-bodied:
The body of the product consists of a solid material, for example, concrete, without any voids. Such slabs have a straight rectangular shape. The thickness is 10-16 cm. Most often they are used to cover underground technical channels.
- Hollow:
Such floors are made in the form of rectangular slabs with small voids around the perimeter (most often round, less often square). The most popular are products with a thickness of 22 cm, while the hole diameter can be 14-15.9 cm. Manufacturers also offer floor slabs with a thickness of 30, 26 and 16 cm.
- Monolithic:
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Such plates are characterized by high strength and wear resistance. They are made from reinforced concrete structures with continuous reinforcement. Recommended for the use of interfloor slabs in residential multi-storey buildings and modern residential complexes.
- Ribbed:
Such products are shaped like the letter P (from the end part). Their main difference is that the edges of the slab are reinforced with special beams. The products are characterized by increased load-bearing properties, so they are often used for floors of public buildings, multi-storey and industrial buildings. Due to the high cost of such a product, it is not advisable to use it when constructing a private house, summer house or country cottage.
- Lightweight:
The main difference between these slabs is their low weight compared to similar slabs. The structure of the product is multi-hollow. It is recommended to install such a floor on those construction sites where the foundation is of insufficient strength. An example of these products are slabs made on the basis of polystyrene concrete.
Types of floors by material
- Concrete floors: such structures are usually used in the construction of large objects (multi-story buildings, industrial workshops, and so on). The main component for their production is concrete of various types: silicate, light and heavy. Concrete floors are divided into several subtypes:
- precast: The overall floor structure consists of several individual concrete slabs bonded together. These are factory-made products;
- monolithic: a solid slab that is concreted to specific dimensions directly on the construction site;
- monolithic on a supporting profiled sheet: the installed corrugated sheet is a permanent formwork for concreting a monolithic slab. As a rule, such structures are used to create interfloor ceilings, which simultaneously serve as a supporting structure and a base for the floor.
- Wooden floors: such structures are characterized by low weight and ease of installation. They are often used in the construction of private houses from various materials: brick, timber, various blocks. Wooden floors are divided into subtypes:
- solid wood beams: the length of the solid wood floor is up to 6 meters.
- glued laminated timber: the length of this type of floor is up to 12 meters.
- Metal floors: metal beams are used to cover large areas with increased load. They are made from high-rolled steel according to the strict requirements of GOST standards.
Features of beam structures
Beam floors are a more economical option compared to slabs.
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The installation procedure is simpler, but the finished structure successfully withstands heavy loads. 
Experts recommend using this type of floors in the construction of private houses or low buildings (up to several floors). The beam web is secured using special supports. Such an overlap is placed horizontally or at some angle. Thus, the load from the beam falls on the supports: walls, columns, and is then redistributed between other structural elements.
The strength of the product, as well as the maximum loads, are determined depending on:
- beam material;
- method of its fastening;
- shape and cross-sectional area.
Truss is another modern way of arranging floors. The design is a rod system. To form it, linear rod elements are used, which are connected at certain nodes, which bear the load. This type of floor includes trussed beams - a structure made of a continuous beam (two- or three-span) and a girder. Similar structures are used for arranging high-rise buildings.
The stability and strength of the entire building, as well as its service life, depend on the correct choice of material for creating floors. When choosing a specific product, first of all, you should take into account the overall architectural design of the construction site. It is important to make some technical calculations so that the finished floor can successfully withstand the required load and be durable and reliable. In addition, the selected products are subject to requirements for thermal conductivity, fire safety, water and sound insulation.
With sufficiently high technical characteristics, the selected structures should have the lowest possible weight and thickness. It is very important not to make mistakes when performing calculations, so it is better to entrust this task to an experienced and qualified engineer.
Advantages and disadvantages of various floors
Most often in construction, reinforced concrete slabs are used as flooring. Compared to monolithic concreting, reinforced concrete structures are characterized by a number of undeniable advantages. Most of the models have voids in their design, which increases the sound insulation of the room, reduces the overall weight of the structure, and, therefore, the load on the foundation of the construction site.
The modern construction industry is increasingly using new building materials made by saturating the original binders with various light components, such as air, slag or wood waste. We are talking about blocks. Their use can significantly speed up the process of constructing the vertical parts of a building for residential and non-residential purposes, and increase the heat and sound insulation properties of the house.
Usually, to separate attic or attic spaces, various types of floors are installed on the main frame. Today we will tell you about the features of choosing and installing floors for a house built from foam blocks.
One of the characteristic properties of block materials, especially those in which various gas mixtures and air are used as filler, is low strength characteristics. They must be taken into account when choosing materials for installing floor elements in order to avoid violating the geometry of the entire house and its strength. In this regard, in the manufacture of the second and third floors, as well as the attic, wooden beams receive the greatest attention.
In addition to reducing the load on the walls of a house made of foam blocks, such elements allow their installation by several workers without the use of specialized lifting devices or construction equipment.
Also, splicing along the length or making laminated veneer lumber allows you to obtain beams reaching a length of about ten meters or more, which, subject to certain wall parameters, allows you to build buildings without internal partitions. Instead of rectangular bars, boards with a thickness of 50 millimeters or more, joined together along planes, can be used.
A peculiarity of the use of wooden beam floors is the need for their additional treatment with various fire and biological protective compounds that prevent the rapid combustion of the wooden parts of the house, as well as their destruction when exposed to various microorganisms. In order to avoid reducing the heat-shielding functions of the walls, floor beams must be laid directly into the upper crown of the walls in the case of attics, or into the masonry and their ends must be carefully insulated with some artificial resins.
In addition, in order to evenly distribute the load from the floor, we recommend making a small reinforced belt of reinforced concrete.
Floors made of steel profiles
Sometimes, instead of wooden beams, steel profiled beams in the form of a channel or I-beam are used. Due to the greater mass, the use of these elements in the construction of floors places higher demands on the organization of the reinforced belt, manufactured along the entire perimeter of load-bearing walls and partitions. To make it, formwork made of panels or boards is installed in the upper part of vertical structures.
A steel frame, knitted or welded from steel ribbed rods, is placed inside it. Subsequently, the entire space inside the formwork is filled with concrete mixture and cured for several weeks to acquire maximum strength.
Monolithic slab
Another option for the base for the floor of an attic or the upper floor of a house made of foam blocks is to make a monolithic slab. The process of obtaining it is associated with a number of features. Firstly, this is the installation of strong intermediate partitions, as well as a significant increase in the thickness of the load-bearing walls. Secondly, the process of pouring a monolith involves the use of a large number of removable supports. Thirdly, such an overlap requires significant consumption of steel reinforcement and concrete mixture, which, on the one hand, significantly increases its cost, and on the other, its weight. The use of a monolith is not recommended without serious preliminary calculations of the strength of the walls, depending on the mass of the floor itself, as well as the weight of the building elements located above (upper floors, attic and roof). Often, in order to maximize the lightness of solid-cast floors, a ribbed slab design is used, giving it minimal weight while maintaining high strength.
Reinforced concrete floors
The last method of making floors for a foam block house is floors made of reinforced concrete slabs. These designs have both standard sizes and are made to order. The production time is quite long, so when planning the installation of non-standard slabs, they must be ordered in advance, at the beginning of construction work. In order to reduce the load on the structure of the entire house, it is better to purchase reinforced concrete products equipped with internal cavities.
During the delivery, unloading and installation of such floors, it is impossible to do without the use of specialized construction equipment. To transport long slabs, long trucks may be required, the rental of which will also leave a significant impact on the total cost of the work. In addition to using the crane, at least three workers will be required to operate the lift, guide and lay it.
The development of foam block production has led to the emergence of enterprises specializing in the production of floor slabs. Unfortunately, there are much fewer such companies in our country than those that produce concrete products. Therefore, not many people manage to purchase them and deliver them to the construction site.
Thus, when choosing a floor material, many different parameters should be considered, paying attention not only to the strength characteristics of each specific material, but also to its cost, as well as the need to use expensive equipment and specialized workers.
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The ceiling must have the necessary load-bearing capacity, minimal deflection, in order to withstand both the load from its own weight and the useful load (static and dynamic). The ceiling must be rigid, i.e., under the influence of loads, it must not give deflections exceeding the values permissible by standards, and have sound-proofing and heat-protective properties. The strength and durability of the entire structure will depend on the quality of the materials used for covering and strict adherence to technology. The type of ceiling is determined by the project; experts, a designer or an architect, can only adapt and change anything themselves. House floors, depending on the location in the building, there are interfloor, attic, basement (basement), etc.
Types of floors
Depending on the materials used for the floors and the design features of the manufacturing and installation technologies, the following are distinguished: types of floors:
- slab floors made of precast reinforced concrete;
- monolithic reinforced concrete floors;
- prefabricated monolithic (frequently ribbed) floors;
- wooden floors.
During construction, a combined solution is also possible: some of the floors are made prefabricated, some are made monolithic. Combinations of various materials are also possible (if this is provided for in advance by the project), for example, an unused attic can be covered with wood, and reinforced concrete can be used for interfloor ceilings.
Factory blanks
The option of floors made from special slabs manufactured at the factory is widely known and often used. Slab floors made of precast reinforced concrete can be solid or hollow, made from light and heavy concrete. Traditionally, hollow core slabs are used for the construction of a private house due to their lower cost and better sound insulation and thermal conductivity. In addition, they weigh less, so load-bearing walls and foundations experience less load. Hollow-core reinforced concrete slabs are manufactured at the factory, their maximum length is about 7 m, thickness is 220 mm. The slabs come with round, oval and polygonal voids that run through the slab along its entire length.
Installation of prefabricated reinforced concrete floors requires the presence of specialized lifting equipment (crane) at the construction site. Laying is carried out on a bed of cement mortar, made in places where it rests on load-bearing walls. Such slabs rest on two sides. The recommended depth of support on load-bearing walls is 10-15 cm. It is necessary to lay the floors in a smaller size, that is, for a cottage of 5x7 m, it is better to use 5-meter slabs. The seams between the slabs are cleared of debris and carefully filled with cement mortar. When installing interfloor ceilings, the slabs are leveled along the bottom surface (at the location of the future ceiling), bringing the horizontal level to the level. If slabs with prestressed reinforcement are used, then they can be supported only on the ends; they cannot be supported by the side edges and the middle of the surface of the slab.
If, after delivery of floor slabs to the construction site, their installation is delayed, it is necessary to ensure that they are stored correctly, because the slabs will quickly begin to deteriorate in the open air. To ensure that the products do not lose their quality, when unloading, it is necessary to fold them horizontally, in a stack, no more than 2.5 m high, lined with wooden spacers.
Reinforced concrete floors
Without resorting to heavy equipment during installation and the services of reinforced concrete and enterprises, it is possible to produce floors of the required format directly on the construction site. This flooring is made of concrete and steel reinforcement. This type is interesting because it is suitable for any planning solutions. In a monolithic floor, the maximum width depends on the thickness and reinforcement of the slab - the thicker and stronger the floor, the wider it can be. On average, with a width of 6 m, a monolithic floor has a thickness of 10-16 cm. The technology makes it possible to create spans 12 m wide or more, but they are not practical for a private house. Monolithic floors can withstand a load of 600-1250 kg/m2 (depending on the thickness and length of the slabs).
The location of the reinforcement (in one or two directions or crosswise), as well as the method of support on the walls, is determined by the project. A slab reinforced in two directions will be thinner than a slab with rods of the same thickness laid in one direction. Arches from steel reinforcing rods are made either using welding technology or knitting technology. The welded frame is made by welding reinforcement rods; a knitted frame is made by tying reinforcement together using soft knitting wire. With this type of flooring, it is necessary to install formwork over the entire area of the future slab. You can use ready-made formwork from manufacturers (rent, for example), or use wooden panels of your own production, where, of course, it is preferable to use plywood, then the finished surface will be smooth, with a minimum of flaws that require elimination during finishing.
When pouring concrete, you must carefully ensure that it is laid completely, that no voids are left, and that the frame is covered. Filling should be done at one time, and not in parts. If work is carried out at sub-zero temperatures, it is necessary to add special anti-frost additives to the concrete, or to heat the installation site.
A monolithic concrete floor acquires full grade strength 28 days after pouring, although you can walk on it after just a few days; the recommended period for resuming construction work (laying the walls of the next floor) is two weeks.
Structural tandem
Also used in private housing construction are prefabricated monolithic (frequently ribbed) floors - structures made of load-bearing reinforced concrete beams and lightweight hollow blocks. The beams are either factory-ready or concreted on site during the construction process. The blocks used can be ceramic, expanded clay concrete, cellular concrete, expanded polystyrene, etc. When installing such a floor, the beams are laid in the direction of the smaller span, supported by the load-bearing walls of the house and the main beams. They are installed in such a way that the hollow blocks, on one side, only touch the inner edge of the wall and are supported by the mounting support, and on the other, they rest on the floor beam. The remaining beams are installed parallel to each other at equal intervals, the size of which depends on the width of the block liners. An installation option is possible when the first row of hollow blocks rests on the wall on one side and on the floor beam on the other. The maximum length of beams is usually 7-8 m, respectively, this is the threshold for the maximum span of the floor. When creating large openings in such a ceiling (stairs, stoves, fireplace chimneys, etc.), additional beams are installed perpendicular to the floor beams. Along the perimeter of all load-bearing walls, a special belt with a height of 23-28 cm is concreted (the ends of the beams extend into it by 8-12 cm). After assembly, the floor is poured with concrete with a layer thickness of 4-6 cm, resulting in a monolithic structure. In general, the thickness of the frequently ribbed floor reaches 20-29 cm. Its weight, depending on the type of filling blocks, ranges from 160 to 340 kg/m2. After pouring concrete, you can walk on the floor within a few days, but the subsequent construction of walls can be continued only after 10-14 days, and it is necessary to avoid the impact of increased loads on the floors, because it will acquire its final strength, like a monolithic one, in a month. With frequently ribbed floors, the correct placement of interior partitions (walls) on the floor is extremely important. Only light structures up to 50 kg/m2 (plasterboard + mineral wool) and walls running perpendicular to the floor beams can be placed arbitrarily. In other cases, precise calculation and accuracy are required. Walls should not be allowed to run parallel to floor beams directly above hollow blocks. This can lead to destruction of blocks, damage to the ceiling, and collapse of the wall.
Floors in a wooden house
In wooden houses, it is possible to install only floors made of a similar material; in buildings built from other materials (brick, stone, monolithic frame technologies), wood serves as an alternative to reinforced concrete. Wooden floors are made from solid or laminated wood. The span, or width of the wooden floor is usually 5-6 m, however, it can reach 12-15 m, the thickness is 20-28 cm. In this case, the thickness of the load-bearing elements of the floor is selected in such a way that during operation they do not sag or springy. By design, there are several types of such floors: beam (the load-bearing element of the beam is 20-40 cm high, 8-20 cm wide. The distance between individual beams in such a floor is quite large - from 60 to 150 cm), ribbed (in ribbed floors the main load-bearing element are ribs located every 30-60 cm. Their length is usually 5-6 m. The cladding on such floors is made of plywood, ordinary chipboards or OSB boards, boards) and beam-ribbed (the load-bearing elements are beams and ribs. Ribs either rest on beams or are attached to them using special metal brackets).
The wooden floor is installed when the walls around the perimeter of the house are brought to the desired level. Part of the wooden beams that will be in the wall must be covered with roofing felt. If this is an external wall, then it is advisable not to bring the beam to the street edge by about 5 centimeters. This space must be sealed after the wall is built.
When installing wooden floors, special attention is paid to the places through which stove, fireplace and boiler pipes pass. The distance between the pipe and wooden structures must be at least 25-35 cm, and a heat-insulating gasket made of non-combustible materials is installed around the pipe.
Wood for beams and ribs should not have large knots or cracks, the workpieces should be smooth, without bark, with a moisture content of no more than 15-20%. All wooden parts of structures are treated with fire retardants and antiseptics. Discussion of this topic on
If you want to build yourself a small cottage or a two-story house, then you will have to face the problem of choosing between floors. After reading this article, you will learn about what they are, as well as the advantages, disadvantages and features of each type of floor.
Interfloor ceilings are an extremely important part of the house; they must not only withstand significant loads, but also have sufficient sound insulation. Agree, it’s unpleasant when on the first floor you can hear every step that is taken on the second floor. Also, interfloor ceilings add strength to the entire structure and take on some of the deformation loads.
All floors are divided into interfloor, attic, basement and basement.
What requirements must the floors between floors meet?
Primary requirements:
- High structural strength, that is, the possession of load-bearing capacity. This parameter must be calculated during design.
- Significant floor rigidity. Deflections and movements, even minimal ones, can lead to the destruction of the entire house. The permissible deflection value for interfloor ceilings should not exceed 1 in 250, and for attic floors - 1/200.
- The overlap should be maximum light, thin. It should not create excessive load on the walls.
- The interfloor ceiling must become a barrier to fire, that is, it must have high fire resistance. This characteristic is regulated by fire safety standards.
- High thermal insulation properties. Floors do not always separate living rooms, but they can separate rooms where there is a significant temperature difference.
- Good sound insulation. This parameter is extremely important, and we must not forget that not only the walls of the building, but also the interfloor floors need this parameter.
All requirements are mandatory and are suitable for any type of floor. Sometimes additional requirements are imposed on interfloor ceilings, for example, water tightness, or gas tightness, or a special appearance.
Types of interfloor ceilings
According to their design, floors are divided into:
- beam- they consist of load-bearing beams and filler;
- beamless- made from homogeneous elements, for example, panels or slabs;
The latter may be:
- from wooden beams;
- with metal beams;
- with reinforced concrete beams.
In this type of floor, the basis is beams placed equidistant from each other. After installing the beams, filling elements are laid between them, which play the role of a fence.
Interfloor ceilings made of wooden beams
This type of flooring is most common in private housing construction, in particular in the construction of wooden, frame and even brick buildings.
Application:
- wooden beams are used as an interfloor ceiling if the span width is no more than five meters;
- as an attic floor, if the attic is not residential and the span is less than six meters.
Most beams are made of pine or larch. On their upper part there is a flooring that can be used as a subfloor.
Advantages of floors made of wooden beams:
- speed of installation - no special devices are needed to erect such a structure;
- light weight - such an overlap will not create a significant load on the walls of the house;
- environmental friendliness - the tree does not contain any harmful substances.
Flaws:
- weak resistance to fire - even with good treatment, the tree will still catch fire;
- there is a chance of beams rotting or being damaged by bark beetles;
- such an overlap will not be able to withstand significant loads.
Beam-type ceilings consist of beams, floors, bevels and insulation.
Interfloor ceilings made on metal beams
If we compare them with the previous type, they are more reliable, durable and significantly thinner than wooden ones. True, floors of this type are not built so often. Lightweight concrete inserts, wooden beams or panels, or reinforced concrete slabs are used as filler.
An I-beam, rolled profile, angle or channel is used as a load-bearing element of this floor.
Advantages of floors on metal beams:
- it is possible to cover a large span (from 6 meters);
- metal beams do not burn, do not rot, and are not afraid of any bug;
- they are very durable.
Negative sides:
- moisture causes metal to rust;
- metal beams have low sound and heat insulation rates;
- the enormous weight of such a ceiling - one square meter can weigh more than 400 kilograms.
To prevent metal beams from “ringing” so much, their ends can be wrapped in felt.
Such floors are erected if the span is from 3 to 8 meters. You can't lift them with your hands, so you definitely need to use a crane. The weight of one beam can reach 400 kilograms.
Advantages of this type of flooring:
- can cover longer distances compared to wooden ones;
- they have higher heat and noise insulation parameters than ceilings on metal beams.
Flaws:
- huge weight and impossibility of installation manually, only with the use of special equipment.
Beamless interfloor ceilings
Such floors do not have a so-called frame and are created using homogeneous elements. The latter are placed close to one another. Slabs or panels are used as elements. They are a monolithic slab, which is both a load-bearing and enclosing structure.
Types of beamless floors:
- prefabricated;
- monolithic;
- prefabricated monolithic.
This type of flooring has gained the greatest popularity in the construction of brick structures. For the construction of this type of floor, two types of panels are used:
- solid- made of lightweight concrete;
- hollow-core- holes are made in them, which act as “stiffening ribs”.
Positive qualities of prefabricated floors:
- they are more durable than wooden ones, and are also not subject to rotting, corrosion, and are not afraid of various bacteria;
- excellent strength - they can withstand significant loads, up to 200 kg/m2.
Negative sides:
- since they have significant weight, when installing them you cannot do without special equipment;
- slabs are usually made only in standard sizes, so they may not fit.
Building this type of floor is quite expensive, but you will pay for quality and durability.
Unlike the previous type, they can be of any shape and size. A monolithic interfloor ceiling is a solid slab with a thickness of 8 to 12 centimeters, made of M200 concrete. The weight of one square meter of this design can reach 500 kilograms.
Advantages of monolithic floors:
- high surface quality;
- no need to carry out additional loading and unloading operations;
- there is no need to seal seams;
- the opportunity to order the kind of ceiling you can imagine.
Flaws:
- It is mandatory to install wooden formwork;
- very heavy, so the load on the walls increases;
- quite high price.
Prefabricated monolithic floors between floors
This type belongs to modern developments. In it, the space between the beams is filled with hollow blocks, and then the entire structure is filled with concrete.
The positive aspects of prefabricated monolithic floors include:
- less weight than reinforced concrete ones, so you can do without special equipment;
- good thermal insulation characteristics;
- the ability to create floors of complex shapes.
Negative points:
- inappropriate for use in low-rise construction, since the process of erecting such a structure is quite labor-intensive.
The choice of flooring largely depends on the size of the spans and the material from which the house is built. For light wooden and frame buildings, wooden beam floors are suitable, and for heavy brick ones it is better to use floors made of metal beams or reinforced concrete. In any case, you should not save on this and during design it is better to consult with a specialist about the choice of flooring.
Video: Soundproofing floors using the example of a wooden house
Marking different types of foundation for a house
