No overlap. Construction of floors between floors: important aspects. Interfloor ceilings: manufacturing options
The ceiling of a private house is a horizontal building element that divides the building in height. It is at the same time the floor of the upper floor and takes on its load along with the furnishings and people. Floors provide the structure with the necessary rigidity, so their construction is very demanding. Structures separating residential floors from attics and basements also perform an energy-saving function. What is the best flooring for a private house made of foam blocks? How to install it yourself? Let's sort out the questions together.
Types of floors
According to the technical solution, interfloor vaults are conventionally divided into 2 groups:
- – floors made of homogeneous elements;
- prefabricated - structures made of beams and filling.
In the production of monolithic structures, concrete is used, which is poured into formwork directly at the construction site. The thickness of the slabs must be at least 150 mm. Such floors are characterized by strength and high load-bearing capacity. In addition, they can be given arbitrary geometric shapes.
The load-bearing part of the prefabricated options are beams. They are wooden, metal, reinforced concrete. The beams are distributed evenly across the top of the floor. Filling elements are placed between them, which serve as fencing.
1. Floors made of wooden beams.
This is the most popular material option for the construction of wooden and frame structures. The basis of the floors is made of laminated veneer lumber from coniferous and deciduous wood. It is lightweight, easy to install and low cost. The entire structure consists of wooden beams, insulation, beading and flooring. It can be used in rooms up to 5 meters wide. The disadvantage of a wood frame is the increased flammability, as well as the likelihood of rotting and damage by pests.
2. Metal ceilings.
Channels No. 12-36 and higher are chosen as the supporting base. To prevent corrosion, they are coated with primer. Wooden logs are laid on top, and the resulting voids are filled with insulating materials with sound insulation. Wooden panels, rolls, and lightweight concrete inserts are well suited for this. Unlike wooden ones, such floors are more reliable and durable. They are thinner, which saves living space. The big disadvantage of metal options is the complexity of installation, so they are rarely found in private houses made of foam concrete.
3. Floors made of reinforced concrete beams.
Products are manufactured at the factory using an industrial method. This is the most popular option used in the construction of cottages. The structure consists of beams made of rolled profiles and hollow reinforced concrete slabs with a thickness of 90 mm or more. Interfloor ceilings have dimensions of 1.3-7.5 m in length and 1-1.5 m in width.
- quick installation;
- high load-bearing capacity;
- good thermal and sound insulation;
- acceptable price.
The disadvantages include the need to use special equipment during installation. The massiveness of the structures requires additional reinforcement of the walls in the form of reinforced frames. In addition, ready-made reinforced concrete slabs have fixed dimensions, which limits the architectural possibilities of a private house.
Requirements for floors
The slabs separating the floors must have strength sufficient to withstand their own and useful mass (people, furniture, household appliances, interior items). The size of the payload per square floor area is determined depending on the purpose of the room and the nature of the objects located in it. Thus, for interfloor ceilings the permissible value is no more than 210 kg/m2. More information about different types of floors can be found.
The slab must have good rigidity, which will not allow it to sag under load. The permissible thickness of floors between residential floors should be no more than 1/250 of the span dimensions.
To ensure reliable sound insulation, all cracks at the junctions of building elements are carefully closed. Any overlap cannot withstand strong and long burning. For each type of material, the maximum fire resistance time is calculated:
- 60 min – reinforced concrete slabs;
- 45 min – wooden structures with backfill and plaster on the lower surface;
- 15 min – wood floors with plaster;
- less than 15 minutes – wooden beams not protected by fireproof materials.
Floors that separate living rooms from a cold attic or basement require additional thermal insulation.
Laying reinforced concrete floors in a private house from foam blocks with your own hands
Reinforced concrete slabs are a strong and reliable foundation for buildings made of cellular materials. At the same time, they have a large mass, which must be taken into account during masonry work. To ensure that the weight of the ceiling is distributed evenly across the floor and does not violate the integrity of the walls, it is better to make an additional device in the form of a reinforcing belt.
Option I:
- Install a concrete strip measuring 150×250 mm along the perimeter of the cottage wall. It is reinforced with a steel rod with a diameter of 10-12 mm and filled with M200 concrete.
- Place the floor slab on the frozen monolithic belt, leaving a gap of 10-20 mm between the end and the wall.
- Attach sheets of extruded polystyrene foam 50 mm thick to the plates. This will help eliminate cold bridges.
Insulating the floor and reinforcing belt does not seem to be a complicated process. Therefore, in order to save money, you can do this work yourself.
Option II:
- Strengthen the wall blocks with reinforcement. To do this, you need to cut deep grooves around the perimeter of the room, lay reinforcing bars in them and secure them with cement mortar.
- Make a distribution tape from baked bricks, placing it above the reinforcement. It consists of three rows sandwiched with a masonry mesh.
The ceiling of the first floor should extend 130-140 mm deep into the wall, maintaining a temperature gap of 10-20 mm. This arrangement ensures the stability and rigidity of the building structure. Brickwork is the most popular type of distribution belt. Its installation does not require the construction of formwork and reinforcement cage, which greatly facilitates and reduces the cost of work.
Technology for installing wooden floors between floors
According to construction experts, timber is the preferred option for a private house with a height of 1-3 floors made of light cellular blocks. The mass of a wooden floor is much less than its reinforced concrete counterpart. It exerts reduced pressure on load-bearing walls, so it looks simpler in design.
- Before laying the floor, build a reinforced belt around the perimeter of the walls. To do this, screw steel rods into the foam blocks every 150 mm and secure them with cement mortar.
- It is better to coat wooden logs with a special protective compound. This will protect the wood from fungus and mold and increase its service life.
- At the ends of the beams that will rest on the walls of the cottage, cut the end part at an angle of 60 degrees. Then wrap it well with a layer of roofing material.
- Fix mineral insulation with sound insulation 50 mm thick in the wall recess.
- Lay wooden logs into the wall to a depth of 140-150 mm. It is better to leave a gap of 20 mm between the insulation and the end of the beam in case of thermal expansion.
A wooden floor, including transportation and installation, is much cheaper than a reinforced concrete structure. In addition, many installation works can be carried out independently.
Expert advice
- When constructing cottages made of foam blocks, you cannot do without reinforcing bars secured with anchors. The longest rod length (75 mm and above) is required for reinforced concrete slabs.
- In prefabricated flooring options, slag and concrete screed are used to connect the elements.
- A technological feature of cellular concrete is its relative softness. Therefore, interfloor floors made of reinforced concrete beams cannot be laid directly on foam blocks. Massive slabs are mounted on a reinforced belt made of heavy concrete or sand-lime brick.
- The installation of a reinforced concrete piping contour around the perimeter of the floor increases the rigidity and strength of the structure. With a section width of 100 mm, its height should correspond to the thickness of the slab.
- Floors between floors are laid only on the main load-bearing walls. It is better to make the internal partitions a little lower.
Interfloor ceilings in a private house
An obligatory element of any building is the interfloor ceiling. This is a loaded part of the building that performs a number of tasks. Overlappings between floors in a private house divide the space inside the building into independent zones. The interfloor structure not only performs a separating function, but also insulates the living space, absorbs noise, and also ensures the rigidity of the building frame. Various building materials are used for the construction, which differ in characteristics and installation technology.
Interfloor covering of a house
What kind of floors should there be between floors in a private house?
The floors between floors are a critical element of the structure, which is subject to a number of requirements. The overlapping base must have the following properties:
- be durable. Under the influence of its own weight and loads from equipment and interior items, cracks should not appear and the rigidity of the structure should not decrease. The level of perceived loads per 1 square meter varies depending on the functional purpose of individual rooms and amounts to 110 kg for attic spaces, and 210 kg for basement and interfloor foundations;
- have high rigidity. Overlapping structures connect the main walls of the building box into a common power circuit, providing an increased level of stability of the structure. Under the influence of forces, a minimum deflection is allowed, which is 1/200 for the bases of attic spaces and 1/250 for floors located above the base;
- reliably soundproof the room. The base must prevent the entry of external noise. The use of effective sound-absorbing materials and sealing of gaps at joining areas can reduce the negative impact of noise factors and create favorable conditions in the room;
- reduce heat loss. The use of thermal insulation materials allows to reduce the thermal conductivity coefficient. By reducing heat loss, the cost of maintaining a favorable temperature is reduced. An increased layer of insulation should be installed above the base, as well as at the attic level;
- resist exposure to open fire and elevated temperatures. If a fire hazard occurs, the ceilings in the house between floors should not allow the fire to spread, temporarily localizing the source of the fire. Fire resistance depends on the material used and is 15 minutes for plastered wood structures, 1 hour for reinforced concrete. Metal structures have a maximum fire resistance threshold.
Floors between floors are a critical element of the structure
The ceilings between floors also make it possible to maintain an individual microclimate in each room, inhibit the penetration of moisture and functionally divide the building into zones.
Ceilings in a house between floors - classification and types
The classification provides for the division of protective structures according to the following criteria:
- location;
- main purpose;
- design;
- construction method.
Based on their placement, protective structures are divided into types with the following purposes:
- attics. They thermally insulate the residential part of the building, creating a reliable barrier with the cold attic. They are constructed using insulation materials that do not collapse under conditions of high humidity and temperature fluctuations. Include a vapor barrier layer;
- interfloor. They divide the interior space of a residential building into separate rooms, each of which has its own purpose and is characterized by a stable microclimate. They do not require the use of moisture-proofing and heat-protective materials and fulfill their main purpose related to sound insulation;
- basement The basement part of the building, which is not heated, and the living rooms are reliably insulated. A layer of insulation prevents heat loss.
Basement floors
Depending on the design features, floors are divided into the following groups:
- beam They are made in the form of horizontal crossbars, filler placed in the space between the beams, and material forming the floor or ceiling;
- beamless. They are made of independent reinforced concrete panels manufactured at factories, or individual slabs reinforced with steel reinforcement;
- combined. This is a prefabricated version of the load-bearing base, made of power beams, between which solid blocks are placed.
Let us dwell on the design features of various floors, analyze their advantages and weaknesses.
In beam-type structures, the load-bearing element is beams installed at equal distances, made of various materials:
- wood;
- metal;
- reinforced concrete.
Let's consider each option.
Wooden beams between floors
Ceilings in a house between floors made of wooden beams
Using beams from coniferous and deciduous wood, you can build a wooden load-bearing structure. The strength of wood imposes certain restrictions on the span size:
- for interfloor foundations - maximum distance 5 m;
- for attic spaces - span size up to 6 m.
Wood flooring includes the following elements:
- load-bearing beams;
- flooring;
- heat insulator;
- ceiling material.
Advantages of a wooden base:
- ease of installation;
- ease of installation;
Wood flooring
- acceptable level of costs;
- small mass.
Disadvantages of timber beams:
- flammability;
- hygroscopicity.
Impregnation with special compounds reduces the fire hazard and reduces sensitivity to moisture.
How to install wooden floors
The installation technology involves performing the following operations:
- Installation of beams impregnated with an antiseptic composition.
- Fastening wooden boards.
- Laying vapor barrier material and insulation.
- Fixation of finished floor and ceiling trim.
To perform installation operations, it is necessary to first calculate the need for materials.
Wooden beams have little mass
Rolled steel used as beams is superior to wood in terms of reliability, strength properties and durability, and also has a lower cross-sectional height compared to wood.
Advantages of rolled metal, which allows the formation of increased spans:
- biological stability;
- durability;
- temperature resistance.
The optimal option for reliable roofing of a private house is determined at the stage of developing design documentation. The choice is influenced by the thickness of the walls, the height of the building, the size of the payload from communications, plumbing fixtures, heating equipment, household appliances, and furniture. Interfloor ceilings divide the house by height and serve as floors or ceilings for adjacent rooms. Horizontal partitions prevent the circulation of cold air and help save energy.
Types of horizontal structures in a private house according to their location:
- basement - insulate underground unheated rooms;
- basement - are the floor for the first floor;
- attic - protect living rooms from the cold and heat of the roof space;
- interfloor (attic) - divide the building by height.
The functional floors of a private house must have:
1. strength, that is, the ability to withstand its own weight, furnishings and equipment of the premises. The payload for attics is 105 kg/cm2, for basements and interiors – 210 kg/cm2;
2. rigidity, which maintains an acceptable deflection of 3 cm. The integrity of the ceiling finish, vibration and creaking of the floor on the upper floors of the cottage depend on this;
3. noise-absorbing properties. Partitions between residential floors are equipped with sound insulation;
4. heat-saving qualities if adjacent rooms have different temperatures. To prevent the formation of condensation, an additional vapor barrier is laid;
5. fire resistance, which provides for safe evacuation in case of fire. Reinforced concrete provides a time reserve of 60 minutes, protected by plaster - a maximum of 45 minutes;
6. a waterproofing layer in the vicinity of cold rooms;
7. biological resistance to fungal microorganisms.
The structure can be prefabricated or monolithic. The former are mounted on beams or using reinforced concrete slabs, the latter are poured into formwork. The strength of the supporting walls, timing and material and technical resources of construction determine the method of constructing the floors. Private houses built from foam blocks require a special approach when choosing a sustainable system. Cellular concrete has insufficient strength and can shrink under heavy loads, so the floors in such cottages are easier to make using wooden beams. The construction of the floors is carried out independently.
Which variety is better to choose?
The load-bearing beams of prefabricated floors rest on the enclosing walls of the cottage. A clean floor is laid on top, a ceiling is lined underneath, and thermal and sound insulation is laid between them. In private houses with supporting walls made of artificial stone, wooden or reinforced concrete beams, metal I-beams or channels are used.
In a cottage made of foam blocks, the first floor can be covered with hollow slabs, which are ordered in advance at the reinforced concrete building. Installation will require the use of lifting equipment and qualified workers. It is necessary to make a closed reinforced belt around the perimeter of the supporting walls.
Monolithic floors between floors are installed after accurate calculations of the load-bearing capacity of foam blocks. This option will require costs for intermediate partitions, increasing the thickness of the walls, reinforced belt, suspended formwork and reliable supports. Pouring involves the use of metal reinforcement and factory-produced concrete, which is continuously supplied to the upper level using pumps. Therefore, you cannot cope with this type of work yourself. The thickness of the concrete does not exceed 15–20 cm, but it will take a month to harden.
When building from foam blocks, accessibility, light weight, and simple installation are the main criteria for choosing a material and method of construction. Wood has all these qualities. The option of using metal I-beams is not suitable for houses made of foam concrete due to their heavy weight and the possibility of corrosion.
Installation of wooden supports
Advantages:
1. relatively small total weight (together with an average payload of maximum 400 kg/m2), compared to reinforced concrete, which is 2 times heavier. Lightening of above-ground structures allows saving on the foundation;
2. availability of various types of lumber. The beams are spliced along their length and glued together from boards of suitable sizes. No special equipment is required for transportation and unloading;
3. simple installation using standard tools allows you to do the work yourself without lifting mechanisms;
4. no need to strengthen the perimeter of the supporting walls with a reinforced concrete belt;
5. savings on foundations, transport, hired workers, material costs;
6. High installation speed and immediate continuation of construction.
The disadvantage is the limitation of the span width. To make the deflection of the beams minimal, columns and retaining partitions are installed in the premises. The laying step is determined by the load and cross-section of the beam. Stable interfloor floors are erected over spans of up to 5 m, and attic floors do not exceed 6 m in width. With an average load of 400 kg/m2, beams with a cross section of 150x200 (225) mm are installed in increments of 0.6 m, 150x225 (175x250) mm at a distance of 1 m .
Before installation, the wood is treated with an antiseptic. After impregnation, a protective coating is applied against fire, mold and insects. Beams are fixed in nests, which are formed during the construction of load-bearing walls. The ends of the beams are cut at an angle of 60°, oiled and wrapped with roofing felt at the points of contact with the stone blocks. The free space of the niches is filled with mineral wool or blown with foam.
First, beams are installed at a distance of 0.5 m from the walls, then intermediate beams are distributed with a certain step. Check the equal level of laying the beams using a laser level. The structure is leveled with oiled boards of the required thickness, which are placed in the sockets under the beams.
Insulation and finishing
The location of the horizontal partition in the cottage determines the use of insulating and finishing materials. The thickness of the floors between floors depends on the height of the beams, the number of layers and the characteristics of the finished flooring. Do-it-yourself reeling device diagram:
- 50x50 mm cranial bars are nailed to the bottom of the side surfaces of the beams. They will support the roll-up and the insulation layer;
- a roll is laid on the bars, which can be done by knocking down shields from boards;
- the shields are connected and attached to the cranial bars;
- if the ceiling is basement, then a vapor barrier film and insulation are laid on the “sub” floor. Waterproofing and a finished floor are laid on top;
- Interfloor floors are lined from below with a vapor barrier coating, then with ceiling boards, plywood or wood boards. After laying the heat and sound insulation, the structure is covered with a steam membrane and floorboards are laid.
Floor boards are impregnated with protective agents, painted or varnished. Linoleum, laminate, and parquet are laid on chipboards. The ceiling is leveled with decorative tiles, boards or plasterboard. Then the finishing coat is applied.
1. Wooden elements are treated with water-based products that are intended for indoor use. Senezh Ognebio, made in Russia, is suitable for this - complex impregnation belongs to the 1st group of effectiveness of protection against fire and the influence of biological factors on wood.
2. The ceiling opening should not exceed 6 m, and the step of laying load-bearing beams should not exceed 1 m.
3. The minimum distance between the support beams and exhaust ventilation shafts is 250 mm.
4. The minimum thickness of the thermal and sound insulation layer is 100 mm between living spaces and 200–250 mm for attic and basement systems.
Expanded clay with a fraction size of 5–10 mm, perlite, slag, dry sand, polystyrene foam or mineral wool are used as insulation. Bulk materials are more accessible, but make the structure heavier. The most acceptable option for a private home - mineral wool has low thermal conductivity, repels moisture and, unlike foam plastic, allows air to pass through.
When building a house, any developer faces the question of choosing an interfloor floor. The three most common types of floors are wooden, monolithic reinforced concrete and prefabricated reinforced concrete, mounted from flat hollow-core slabs. It is this type of flooring, as the most popular and practical for low-rise construction, that will be discussed in this material. From this about interfloor ceilings in a private house you will learn:
- What is the difference between hollow-core floor slabs (PC) and floor slabs made by formless molding (PB).
- How to lay floors correctly.
- How to avoid installation mistakes.
- How to store floor slabs.
How to choose a hollow core slab
At first glance at hollow-core floors, it may seem that they differ from each other only in length, thickness and width. But the technical characteristics of hollow-core floor slabs are much broader and are described in detail in GOST 9561-91.
Hollow core slab, private house.
Hollow-core interfloor slabs differ from each other in the method of reinforcement. Moreover, reinforcement (depending on the type of slabs) can be performed using prestressed reinforcement or without prestressed reinforcement. More often, floors with prestressed working reinforcement are used.
When choosing floor slabs, you should pay attention to such an important point as the permissible number of sides on which they can be supported. . Usually you can only support on two short sides, but some types of slabs allow support on three or four sides.
- PB. Provides support on two sides;
- 1pc. Thickness – 220 mm. The diameter of the round voids is 159 mm. Allows support on two sides only;
- 1PKT. Having similar dimensions, it allows support on three sides;
- 1PKK. Can be leaned on four sides.
Floor slabs also differ in their manufacturing method. There is often a debate about what to prefer – PC or PB.
Andrey164 User FORUMHOUSE
The time has come to cover the basement floor of the building with floor slabs, but I can’t decide what to choose - PC or PB, PB has a better surface finish than PC, but I heard that PB are used only in monolithic-frame houses and country houses, and the end Such slabs cannot be loaded with a wall.
Sasha1983 User FORUMHOUSE
The main difference between the plates lies in the technology of their manufacture.
PC (thickness from 160 to 260 mm and typical load-bearing capacity of 800 kg/sq.m.) is cast in formwork. PB brand panels (thickness from 160 mm to 330 mm and typical load-bearing capacity from 800 kg/sq.m) are manufactured using formless continuous casting (this allows for a smoother and more even surface than PC panels). PBs are also called extruder ones.
PB, due to prestressing of the compressed and tensile zones (prestressing of the reinforcement is done at any length of the slab), is less susceptible to cracking than PC. PCs with a length of up to 4.2 meters can be produced without prestressed reinforcement and have a greater free deflection than PB.
At the customer's request, PB can be cut to individual specified sizes (from 1.8 to 9 meters, etc.). They can also be cut lengthwise and into individual longitudinal elements, as well as making an oblique cut at an angle of 30-90 degrees, without losing its load-bearing capacity. This greatly simplifies the layout of such floor slabs on a construction site and provides greater freedom to the designer, because The dimensions of the building box and load-bearing walls are not tied to standard PC dimensions.
When choosing PC interfloor slabs (more than 4.2 meters long), it is important to remember this feature - they are prestressed with special stops at the ends of the slab. If you cut off the end of the PC, the stop (cut off together with the end of the PC and the vertical reinforcement) will not work. Accordingly, the working reinforcement will cling to the concrete only with its side surface. This will significantly reduce the load-bearing capacity of the slab.
Despite the better quality smooth surface, good geometry, lighter weight and high load-bearing capacity, this point should be taken into account when choosing a PB. Hollow holes in the PC (depending on the width of the slab, with a diameter of 114 to 203 mm) make it possible to easily punch a hole in it for a sewer riser with a diameter of 100 mm. While the size of the void hole in the PB is 60 mm. Therefore, to punch a through hole in a PB brand panel (so as not to damage the reinforcement), you should check with the manufacturer in advance on how best to do this.
Floor slabs for a private house: installation features
PB (unlike PC) does not have mounting loops (or you have to pay extra for their installation), which can complicate their loading, unloading and installation.
It is not recommended to use the “folk” method of installing the PB, when the fastening hooks cling to the end of the hollow hole. In this case, there is a high probability that the hook will be torn out of the hole due to the destruction of the end of the slab, or the hook will simply slip off. This will cause the slab to fall. Also, at your own peril and risk, you can use a method in which a crowbar is inserted into the hollow holes of the PB (two crowbars on one side of the slab) and hooks cling to them.
Installation of PB slabs is allowed only with the use of soft chocks or a special traverse.
ProgC User FORUMHOUSE
To pull the joist out from under the slab, when laying it, leave a gap of 2 cm to the adjacent slab. Then we move the already laid slab with a crowbar to the adjacent one.
Max_im User FORUMHOUSE
Personal experience: I laid slabs at my construction site using this method. The gap was left at 3 cm. The slabs were laid on a cement-sand mixture 2 cm thick. The mixture acted as a lubricant, and the slabs were easily moved with a crowbar to the distance I needed.
Also, when installing floor slabs, it is necessary to comply with the calculated values of the minimum depth of support for the slab. The following numbers can be used as a guide:
- brick wall, minimum support depth is 8 cm, maximum support depth is 16 cm;
- reinforced concrete – 7 cm, maximum support depth – 12 cm;
- gas and foam concrete blocks - at least 10-12 cm, optimal support depth - 15 cm;
- steel structures – 7 cm.
It is not recommended to support the floor slab more than 20 cm, because as the depth of support increases, it begins to “work” like a pinched beam. When laying floor panels on walls built with gas and foam concrete blocks, it is necessary to install a reinforced concrete armored belt, which is described in detail in the article:. Read also our article, which explains in detail. We wish you to successfully apply the acquired knowledge on your construction sites!
Before installing the slabs, it is recommended to seal the ends of the hollow holes. The voids are sealed to prevent water from getting inside the panel. This also increases the strength at the ends of the slabs (this applies to a greater extent to PC than to PB) if load-bearing partitions are supported on them. The voids can be filled by inserting half a brick into them and “filling” the gap with a layer of concrete. Typically, voids are sealed to a depth of at least 12-15 cm.
If water does get inside the slabs, it must be removed. To do this, a hole is drilled in the panel, in the “void,” from below, through which water can flow out. This is especially important to do if the floors have already been laid, and the house went into winter without a roof. In cold weather, water can freeze inside the hollow hole (since there is nowhere for it to flow out) and tear the slab.
Sergey Perm User FORUMHOUSE
I had slabs laid on the floor for a whole year. I specially drilled holes in the “voids” with a hammer drill, and a lot of water flowed out. Each channel must be drilled.
Before laying floor slabs, it is necessary to select a truck crane with the required lifting capacity. It is important to take into account the accessibility of access roads, the maximum possible reach of the boom of the truck crane and the permissible weight of the load. And also calculate the possibility of laying floor panels not from one point, but from both sides of the house.
zumpf User FORUMHOUSE
The surface on which the floor slab is laid must be level and free of debris. Before laying the panel, a cement mixture, the so-called, is “spread”. mortar “bed”, 2 cm thick. This will ensure its reliable adhesion to the walls or armored belt. Also, before installing the panels and before applying the mortar to the wall, you can lay a reinforcing rod with a diameter of 10-12 mm.
This method will allow you to strictly control the vertical mixing of all slabs when laying them (since the panel will not fall below the rod). The rod will not allow it to completely squeeze out the cement mortar from under itself and lie down “dry”. It is not allowed to install slabs in steps. Depending on the length of the slabs, the discrepancy between the ends should not exceed 8-12 mm.
A serious mistake during installation is covering two spans at once with one slab, i.e. it rests on three walls. Because of this, loads unforeseen by the reinforcement scheme arise in it, and under certain unfavorable circumstances, it may crack.
If such a layout cannot be avoided, to relieve stress, a cut is made with a grinder along the upper surface of the panels, exactly above the middle partition (wall).
Another point that you should pay attention to is how to block a flight of stairs between floor slabs if there is nothing to support them on. In this case, you can run two channels parallel to the slabs, and place one across, along the edge of the opening, tie the reinforcement cage in the form of a mesh with a cell of 20 cm and a rod diameter of 8 mm, etc. Place the formwork and fill the monolithic area. There is no need to tie the channel to the floor slabs. In this case, they rest on two short sides and are not subject to loads from the support unit of the flight of stairs.
How to properly store floor slabs on site
Ideally, if the panels are brought to the site, they should be installed immediately. If for some reason this cannot be done, the question arises: how to properly store them.
To store the slabs, it is necessary to prepare a solid and level area in advance. You can't just put them on the ground. In this case, the lower slab may rest on the ground, and, due to the uneven load, it will break under the weight of the upper slabs.
Products should be stacked in a stack of no more than 8-10 pieces. Moreover, spacers are placed under the bottom row (from timber 200x200 mm, etc.), and all subsequent rows are placed through spacers - a 25 mm thick inch board. The spacers should be located no further than 30-45 cm from the ends of the slabs, and they should be positioned strictly vertically one above the other. This will ensure uniform load redistribution.
, and read about e. The video reveals everything
In this article we will look at the main types of floors and the materials from which these floors are constructed. So, what are overlaps? Floors are a structure that divides adjacent rooms in height, that is, it forms floors and separates them from attics and basements.
Basic requirements for floors
- Floors must have sufficient strength to withstand the load both from its own weight and useful (furniture, equipment, people in the room, etc.).The amount of payload per 1 m2 of flooring is set depending on the purpose of the room and the nature of its equipment. For attic floors, the payload should be no more than 105 kg/m2, and for basement and interfloor floors 210 kg/m2.
- The ceiling must be rigid, that is, it must not deflect under loads (the permissible value is from 1/200 for attic floors to 1/250 of the span for interfloor floors).
- When installing the floor, a sufficient degree of sound insulation must be provided, the amount of which is established by standards or special recommendations for the design of buildings for a particular purpose. To do this, it is necessary to carefully close the gaps in the places where the material joins, in order to avoid the transfer of sound from neighboring rooms located above or below.
- Floors separating rooms with a temperature difference of 10 °C (for example, separating a cold basement from the first floor or an attic from the first floor) must meet the requirements of thermal protection, that is, it is necessary to increase the layer of thermal insulation.
- No floor structure, especially wood, can withstand prolonged exposure to fire, but each material has its own fire resistance limit. The fire resistance limit of reinforced concrete floors is 60 minutes; wooden floors with backfill and lower plastered surface - 45 minutes; wooden floors protected with plaster, about 15 minutes; There are even fewer wooden floors not protected by fireproof materials.
Types of house floors
- interfloor (separating residential floors, including the attic),
- basement (separating the basement from the residential floor),
- basement (separating the residential floor from the cold underground),
- attic (separating the residential floor from the unheated attic).
According to its design solution, the load-bearing part of the floors can be divided into:
- beams, consisting of a load-bearing part (beams) and filling;
- beamless, made from homogeneous elements (flooring slabs or flooring panels).
Types of floors for the home
Beam floors
In beam floors, the load-bearing base consists of beams located at the same distance from each other, on which filling elements are laid that perform enclosing functions. Beams can be wooden, reinforced concrete or metal.
Floors made of wooden beams
In private housing construction, the most popular are wooden beam floors, usually used in wooden and frame houses.
For wooden beams there is a limitation on the width of the span (room). They can be used for:
- interfloor ceilings - with a span width of 5 meters;
- for attic floors (with an unused attic space) with a span width of up to 6 meters. Metal beams can be used for any span width.
The wooden floor is made from wooden beams of coniferous and hardwood. On the upper side of the beams there is a flooring, which also serves as the floor. The structure of the beam floor consists of the beams themselves, the run-up, the floor and the insulation.
With a rectangular house plan, it is advisable to block the span along the short wall.
Scheme for laying floor slabs along a short wall
To prevent beams from bending under the weight of the floor, they must be placed at a certain distance (see table). The section of the beam is determined based on the load falling on it.
For example: You need to build a floor measuring 3.0 * 4.0 m. We lay wooden beams (section 6x20) along a wall equal to 3.0 meters. If the ceiling is between floors, the beams are laid at a distance of 1.25 m from each other, if the attic floor is 1.85 m. That is, the larger the span of the future floor, the smaller the distance between the beams will be, since a larger area of flooring accounts for more loads
The distance between the beams is also affected by the thickness of the floor boards. If they are 28 mm or less thick, the distance between the beams should not exceed 50 cm.
Advantages of wooden flooring:
- The main advantage is that a wooden floor can be quickly and easily installed in any (even difficult) place, without the use of any special means, that is, you can do without a crane or other equipment. The wooden floor is light and relatively inexpensive.
Disadvantages of wooden floors:
- The main disadvantage of wooden floors is the increased flammability, sometimes the possibility of rotting and infection with bark beetles.
Wooden floor installation technology:
Installation of beams: Before installing the beam, it must be treated with an antiseptic solution. If the beams rest on a stone or concrete wall, then its ends must be wrapped in two layers of roofing material. The beam is inserted into the nest prepared during the construction of the wall. When inserted into the nest, the beam should not reach the rear wall by 2-3 cm. The end of the beam is made beveled.
Beam installation diagram
(1 - beam, 2 - roofing felt, 3 - insulation, 4 - mortar).
The remaining free space in the nest is filled with insulation; you can fill it with polyurethane foam.
Installation of rewind: Bars (section 4x4 or 5x5), which are called cranial, are nailed to the side faces of the beams.
Scheme of rolling wooden panels
(1 - wooden beam, 2 - cranial block, 3 - roll-up shield, 4 - vapor barrier, 5 - insulation, 6 - finished floor finishing, 7 - ceiling finishing).
A roll of wooden panels is attached to these bars. The roll-up is made from boards made of longitudinal boards or boards from transverse boards. The knurling plates must be pressed tightly against each other. They are attached to the cranial block with self-tapping screws. The roll-up serves as preparation for attaching a “clean” ceiling.
Insulation gasket: An integral part of a wooden beam floor is insulation, which primarily performs the role of sound insulation in the interfloor ceiling, and also serves as thermal insulation in the attic floor. First of all, you need to decide what material to use. The insulation material can be mineral wool, polystyrene foam, slag, perlite, expanded clay, as well as dry sand, sawdust, shavings, straw, and wood leaves. Mineral wool is a lightweight material, easy to use, unlike foam plastic, it “breathes”, has sufficient heat and sound insulation, in general, in most cases, wool is suitable for both insulating interfloor and attic floors. Expanded clay (fraction 5-10 mm) is a heavier material than mineral wool, which makes the structure heavier (the weight of 1 m2 of expanded clay ranges from 270-360 kg).
After fixing the bead, a layer of thermal insulation is placed on top of it. First, a layer of roofing felt, glassine or vapor barrier film is laid between the beams, bending it about 5 cm onto the beams and we proceed to thermal insulation. The thickness of any insulation for an interfloor floor should be at least 100 mm, and for an attic floor, that is, between a cold and heated room - 200-250 mm.
Cost and consumption of materials: The consumption of timber for traditional wooden floors is approximately 0.1 m3 per 1 m2 of flooring at a depth of 400 cm. The average cost of a cubic meter of wooden beams is from 145 dollars (or 14 dollars per linear meter). And the cost of the boards will cost you about $200 per cubic meter. Costs for 1 square meter of flooring using wooden beams range from $70 and above.
Floors on metal beams
Compared to wooden ones, they are quite reliable and more durable, and also have a smaller thickness (save space), but such floors are rarely erected. To fill the openings between the beams, you can use lightweight concrete inserts, lightweight reinforced concrete slabs, wooden panels or wooden slabs. The weight of 1 m2 of such flooring often exceeds 400 kg.
Advantages:
- A metal beam can cover large spans (4-6 meters or more).
- The metal beam is non-flammable and resistant to biological influences (rot, etc.).
But flooring on metal beams is not without its drawbacks:
- In places of high humidity, corrosion forms on the metal.
- In addition, such floors have reduced heat and sound insulation qualities. To mitigate this disadvantage, the ends of the metal beams are wrapped in felt. In such floors, the load-bearing element is a rolled profile: I-beam, channel, corners.
Rolling profile
Prefabricated reinforced concrete hollow slabs 9 cm thick are laid between the beams. A layer of slag and reinforced concrete screed 8-10 cm thick is applied over the reinforced concrete slabs. Steel consumption is high - 25-30 kg/m2, depending on the grade of steel from which the beams are made.
Scheme of the design of a prefabricated reinforced concrete floor slab on metal beams
1 - “clean” floor; 2 - boardwalk; 3 - beam; 4 - prefabricated reinforced concrete slab; 5 - waterproofing; 6 - plaster mesh; 7 - plaster.
Material cost: The price of a steel profile ranges from 7 to 18 dollars/linear meter. The cost of lightweight reinforced concrete slabs is from $110 per piece. For 1 square meter of flooring on metal beams you will spend from $100 and more.
Floors made of reinforced concrete beams
They are installed on spans from 3 m to 7.5 meters. The work is complicated by the need to use lifting equipment. The weight of such beams is 175 - 400 kg.
Advantages:
- With the help of reinforced concrete beams it is possible to span larger spans than with wooden ones.
Flaws:
- To install the floor on reinforced concrete beams, it is necessary to use lifting equipment.
Installation: Reinforced concrete beams are laid at a distance of 600-1000 mm. The filling of the inter-beam space is arranged in the form of lightweight concrete slabs or hollow lightweight concrete blocks (for plank or parquet floors, slabs are used, and for linoleum floors or parquet on a concrete base, hollow blocks are used).
Scheme of the design of a lightweight concrete slab on reinforced concrete beams
(1 - reinforced concrete beam, 2 - lightweight concrete slab, 3 - cement screed and substrate, 4 - parquet, laminate)
Scheme of the design of a floor slab made of hollow blocks on reinforced concrete beams
(1 - reinforced concrete beam, 2 - hollow blocks, 3 - cement screed, 4 - linoleum)
The seams between the beams and slabs are filled with cement mortar and rubbed. Attic floors must be insulated, interfloor floors must be soundproofed, and basement floors must also be insulated.
Floor slabs made of hollow blocks on reinforced concrete beams
Cost: For one linear meter of beam you will have to pay from 25 dollars. The price for one lightweight concrete block is from 1.5 dollars. As a result, for 1 square meter of flooring on reinforced concrete beams you will spend from 65 dollars.
Beamless floors
They are homogeneous elements (slabs or panels) laid close to each other or a solid monolithic slab, which simultaneously serve as load-bearing and enclosing structures. Depending on the manufacturing technology, beamless floors can be prefabricated, monolithic or prefabricated monolithic.
Prefabricated reinforced concrete floors
The most popular, especially in brick houses. To install reinforced concrete floors, two types of panels are used: solid (they are made mainly from lightweight concrete) and hollow-core. The latter have round holes, a kind of “stiffening ribs”. Panels are selected depending on the width of the span to be covered and load-bearing capacity.
Advantages:
- Reinforced concrete slabs have high strength and are designed for a payload of over 200 kg/m2.
- Unlike wood, concrete is not afraid of dampness and does not require any maintenance.
Flaws:
- When installing floors made of reinforced concrete slabs, lifting equipment is required.
- It is not always possible to purchase ready-made slabs of the required size, since they are made in standard sizes at the factory.
Scheme of a beamless floor for a house
Installation: Floor slabs are laid on a layer of cement mortar grade 100. The support of the slabs on the walls (walls more than 250 mm thick) must be at least 100 mm. The seams between the slabs must be cleared of debris and thoroughly filled with cement mortar.
Approximate cost of the material: The cost of one floor slab starts from $110. For 1 square meter of flooring made of reinforced concrete slabs you will spend at least 35-40 dollars.
Monolithic reinforced concrete floors
Can be of various shapes. Monolithic reinforced concrete floors are a solid monolithic slab 8-12 cm thick made of grade 200 concrete, supported by load-bearing walls. The weight of a square meter of a monolithic floor with a thickness of 200 mm is 480-500 kg.
Photo of reinforcement of a monolithic reinforced concrete floor
Installation of monolithic floors is carried out in four stages:
- Installation of steel load-bearing beams in prepared places;
- Installation of suspended wooden formwork from unedged boards (suspended from steel beams);
Installation of suspended wooden formwork from unedged boards
- U masonry reinforcement (diameter 6-12 mm);
- Concreting the floor slab with M200 concrete.
Advantages of a monolith:
- The absence of expensive loading and unloading operations and a higher quality concrete surface that does not require sealing joints, as well as the ability to implement complex architectural and planning solutions.
The disadvantages of monolithic floors include the need to install wooden formwork over almost the entire area of the future floor. However, this does not mean that the formwork needs to be installed all at once. The overlap can be done in separate spans, moving the formwork as the concrete sets.
Installation: Before proceeding with the installation of the ceiling, it is necessary to construct the formwork (it can be purchased ready-made or rented), which consists of telescopic racks, tripods, uniforks, beams, flooring and plywood. Formwork made of wooden and aluminum beams allows you to form floors of any configuration - rectangular, cantilever and even round. Sheets of plywood are placed on the upper wooden part of the beam to form the formwork for pouring concrete. Next, the reinforcement frame is installed and secured. The ends of steel rods 60-80 cm long are bent and tied with wire and reinforcement. Then, concreting is carried out over the entire area of the ceiling to a height of 10-30 cm. Complete adhesion of the concrete occurs after 28 days.
Formwork for a monolithic floor slab made of wood flooring and plywood
Installation of a reinforcement cage in the formwork for the construction of a monolithic reinforced concrete slab
Approximate cost of material: The cost of floor formwork, with wooden and aluminum beams, starts from $40. The approximate consumption of reinforcement for the floor is 75-100 kg/m3 of concrete. The cost of 1 ton of reinforcement is $650. The cost of 1 cubic meter of ready-made concrete is from $130. As a result, the price for 1 square meter of monolithic flooring will cost you from $45 and above (without the cost of formwork).
Prefabricated monolithic floor
A more modern solution for the installation of floors. The bottom line is that the space between the floor beams is filled with hollow blocks, after which the entire structure is poured on top with a layer of concrete.
Prefabricated monolithic flooring for a house
Advantages:
- Installation without the use of lifting mechanisms, improvement of thermal insulation properties, possibility of constructing floors of complex shapes, reduction of construction time.
Flaws:
- The disadvantages include that the prefabricated monolithic structure has a labor-intensive (manual) installation process, which is not advisable when building a house with 2-3 floors.
Installation: During installation, prefabricated monolithic floor beams are laid on the walls at intervals of 600 mm. The weight of a linear meter of beam does not exceed 19 kg. This allows, in most cases, the installation of beams without the use of a crane. Hollow blocks are laid manually on the beams. The weight of the expanded clay concrete block is 14 kg, the polystyrene concrete block is 5.5 kg. As a result, the dead weight of one square meter of the original floor structures is 140 kg for expanded clay concrete blocks and 80 kg for polystyrene concrete blocks.
The floor structure prepared in this way performs the function of permanent formwork, on which a layer of monolithic concrete of class B15 (M200) is laid.
Before pouring concrete, it is necessary to reinforce the structure with reinforcing mesh with cells measuring 100x100 mm made of wire with a diameter of 5-6 mm.
The weight of one square meter of finished flooring is 370-390 kg for expanded clay concrete blocks and 290-300 kg for polystyrene concrete blocks.
Expanded clay concrete block for prefabricated monolithic flooring
Approximate cost: The cost of prefabricated monolithic floor structures (beams and blocks) will cost you 40-50 dollars/m2. The cost of finished floor structures (beams + blocks + mesh + concrete) is 70-75 dollars/m2.
Thermal and sound insulation of floors:
The thermal protection of the ceiling must be such that the temperature on the floor surface is close to the internal air temperature and does not fall below it by more than 2°C. To avoid dampness between heated and unheated rooms, a layer of glassine should be placed above the thermal insulation to protect the insulation layer from moisture.
Scheme of laying heat and sound insulating materials in the ceiling
(1 - wooden beam, 2 - skull block, 3 - roll, 4 - layer of insulation, 5 - vapor barrier film or glassine, 6 - boards)
In addition to good thermal protection, floors must also provide sufficient sound insulation of the premises. In accordance with current standards (data for the Russian Federation), the insulation index Rw must be equal to or greater than 49 dB.
For hollow-core reinforced concrete slabs with a thickness of 220 mm, the insulation index is Rw = 52 dB.
For wooden floors (280 mm insulation layer + one 12 mm layer of plasterboard) the sound insulation index is 47 dB.
Now a little about insulation. Ready-made mineral wool slabs performed well as thermal insulation. In addition to the well-known insulation with ready-made mineral wool slabs, there are alternative options that are carried out on site. For example: You can pour slag or ordinary sawdust onto a sheet lined with roofing felt or covered with a solution of clay with the addition of sand (the solution must dry well). By the way, they are 4 times lighter than slag and at the same time provide 3 times better thermal insulation with the same layer thickness. So, at a winter temperature of -20°C, the backfill of slag should be 16 cm thick, shavings - 7, and sawdust - only 5 cm.
You can make sawdust concrete slabs for the same purpose yourself. To do this, you can take 1 volume part of sawdust, 1.5 parts of lime mortar or 4 parts of clay, 0.3 parts of cement and from 2 to 2.5 parts of water. The finished slabs are dried in the shade, laid on a roofing felt pad, and the seams are sealed with clay or lime mortar. A square meter of such a slab weighs about 5-6 kg with a thickness of 10 cm.
What kind of flooring should you choose for your home? It all depends on the type of house, as well as on the installation technology and price of this ceiling. To conclude this article, I will provide a table in which you can compare different types of floors and choose the most suitable one for yourself.
Attention: Prices in this article are presented for the period of 2008. Be careful!