Do-it-yourself foundation slab step-by-step instructions: how a monolithic foundation slab is constructed and stages of construction. Monolithic ceiling with your own hands How to make a monolithic foundation

Installation of a monolithic countertop in 2 days.

The test was carried out by foreman Sergei Shestero.

Many people have asked me to tell you how we make two-level countertops under washing machines. See post: DIFFERENT BATHROOMS AND COUNTERTOPS. I promised them this. I keep what I promised.

A little background (couldn't resist). We received an apartment for renovation with a difficult fate. Before us, it had been under repair for 5 months. Customer from Khabarovsk. I bought an apartment in Moscow, found a local foreman, agreed with him to renovate the apartment and moved to my place. The foreman regularly reported to him on the completion of the work. The customer regularly sent him money for materials, for work and for finishing materials. When I arrived in December for the surrender, I was completely knocked out. The horse was not lying there, but before the surrender it was like before China. The workers (or rather, one person with a “foreman”) quickly left, leaving the apartment in a terrible state.

The client contacted me through friends. When I came to the apartment and saw all this disgrace, I was shocked. And when I found out how much money he had already spent on this pseudo-repair...

The customer turned out to be a good guy and we started the repairs.
It's a pity that there were no photos left before the alterations began. But this is enough for complete sensations.

I will briefly describe what I saw.

The screed was almost all buckled, the plaster walls were all cracked (there was no gap with the ceiling, everything was caulked with mortar), the heating distribution was made from pipes for drinking water, electrical wiring is absolutely terrible.

We removed all the tiles in the bathroom. Take a closer look: in the toilet installation there is a hot water and hot water collector hidden inside (Miracles on bends)

When the slopes were removed, I was completely devastated. To dislike the customer so much and make him such a waste...

Now let's get down to our rams, or rather our table top. We waterproofed the walls and strengthened them, installed water and sewer lines, and installed a thoroughly bathtub. This is the picture before the installation of the countertop begins.

About 5 - 6 years ago, when we just started offering clients to install countertops, the work was completely different. We used angle iron, welding, and DSP sheets. It was a whole production for a week.

Now practice has shown that everything can be simplified, while the quality remains high. Saving time and money. So take a look, if you like it, use it. Made by one master in 2 days.

First day. A frame is made from a regular TIGI KNAUF profile to fit the size washing machine. If necessary, I can give you the size later (usually a frame margin of 3 cm on each side). Sheets for sheathing - 12 mm GVL is used. Modification of the tabletop depends on the wishes of the customer. In this version it has a rounded edge.

The walls were reinforced; entry into the walls is 6 cm (this is plaster). Plus masonry mesh. We hide the sewerage with a false wall. The tabletop will hang cantilever.

Reinforcement 10 mm. The fittings are set at a slight angle.

We cover the edge with gypsum board, except for the semicircular part, there is gypsum board.

The sink will stand on the countertop; we will not reinforce the space for the drain.

Second day. Half an hour of work.
All! The countertop is flooded.

We put penoplex at the drainage point (you can use a foam block), then you can easily knock it out without a hammer drill.

One of the options for the foundation for a building is a floating monolithic slab. It comes in both shallow and non-recessed types. This type of foundation is not suitable for projects that include a basement. This disadvantage is compensated by the affordable price and the possibility of building a monolithic foundation on problematic soils, since it efficiently distributes and transfers prefabricated loads to the soil.

Different types of foundation slabs

a simple pillow without stiffeners;
slab with simple stiffeners;
slab with reinforced stiffeners.

There are combinations of these options, for example, a strip-slab foundation. It is used if it is necessary to arrange a basement. A popular solution is a slab with stiffeners. It has maximum strength.

The monolithic slab is made using continuous reinforcement. Its thickness depends on the planned building, and ranges from 25 to 55 cm. The use of a shallow version of the slab allows savings in materials of up to 35-40%.

To build a reliable foundation, it is necessary to use only high-quality concrete mixture and reinforcement.

When constructing a monolithic slab, you should adhere to building rules and regulations. Almost all problems with building frames occur due to miscalculations or errors during foundation installation.

The advantages of a monolithic slab as a base are:

the construction budget is lower than analogues;
ease of construction of a monolithic foundation;
ability to withstand high loads due to the large contact area;
no deformation of the walls, since the slab rises and falls evenly;
savings on finishing works, slab - finished subfloor;
Possibility of construction on problematic soils.

Literature on standards and rules

To find out how to pour a monolithic slab with a long service life, it would be a good idea to familiarize yourself with and take into account the requirements:

SNiP in the section “foundations of structures and buildings”;
GOST “classification of soils”;
set of rules for the construction of reinforced concrete and concrete structures.

Stages of preliminary work

From the very beginning it is necessary to carry out the following work:

geological study of the site - measure elevation changes and determine the type of soil;
remove the soil layer at the site of the foundation and deepen the pit to the calculated depth;
lay the necessary communications or bookmarks for them;
lay a drainage system;
arrange a cushion of sand and crushed stone;
waterproof the foundation base;
install formwork;
build a load-bearing frame from reinforcement with a cross-section of 12-14 mm, welded or tied with special wire.

Carry out other work if necessary. To strengthen the structure and stabilize the geometry, it is necessary to provide stiffening ribs at the bottom of the slab.

Rules for pouring a monolithic slab

Typically, the foundation slab is poured in one step. But sometimes you have to do this in several approaches. To do this, select a part that will be filled to its full height, and fence it off with a vertical partition at an angle to the horizontal so that the resulting seam is inclined.

Contractors consider it wrong to fill monolithic foundation houses in parts. But for independent work this is completely acceptable.

Selecting the brand and class of concrete

Before pouring a monolithic foundation slab, you need to order concrete from a reliable supplier. For a monolithic base, you need to choose concrete that meets the following requirements:

mixture density from 1850 to 2400 kg/m³;
concrete grade from M200 or more;
concrete class from B-15 and higher.

IN middle lane suitable commercial concrete grade 250, strength 230 kg/cm², frost resistance F200, water permeability W4 and mobility P3.

The frost resistance of concrete depends on the presence of pores in the concrete structure. During crystallization, water expands and fills them, preventing cracking.

When making the mixture yourself, you must adhere to the technology for preparing concrete with frost resistance from F100 to F150.

Depending on the planned structure and type of soil, it is recommended to choose the following grades of concrete for pouring a monolithic foundation slab:

M400 - for heavy buildings made of brick or concrete, on soft soils;
M350 - for 2-3 storey buildings made of lightweight materials, for example, foam concrete;
M250 - for wooden houses;
M200 - for houses built using frame technology.

At self-production Mixtures for concreting slabs use crushed stone/sand/cement ratios of 3:1, 5:1.

Important points in foundation construction

When building monolithic foundation slabs with your own hands, there are recommendations to maximize their service life. They relate to some stages of work and design features:

The recommended height for supplying concrete from a concrete mixer is no more than one meter. Avoid moving concrete more than two meters. Move the concrete mixer around the perimeter or use a concrete pump to fill the entire area.
The total thickness of the concreting layer is selected at the design stage, depending on the future structure.
The height of the formwork is set 5-10 cm above the slab level.

To increase the bearing capacity of the foundation, the following techniques are used:

the arrangement of stiffeners occurs along the entire perimeter and, additionally, perpendicular to the long wall;
additional piles are installed at junction points (corners of the building).

A structure with piles is called a pile-slab foundation.

For a visual representation of the main stages of construction, you can watch a video on the construction of a monolithic slab foundation.

Nuances of reinforcement of a monolithic slab

When pouring the foundation, remember that all metal elements of the load-bearing frame must be covered with a layer of concrete of at least 15 mm. For convenience, special supports with a thickness of 15-20 mm are placed under the frame from below. It is not recommended to use such stands made of wood, reinforcement or crushed stone. The upper load-bearing frame is attached to vertical sections of reinforcement using welding or binding wire. When leveling and distributing the mixture, you should not walk on the reinforcement so as not to disturb their structure. To distribute the load, use boards or boards, removing them as they are filled.

The monolithic slab can be buried 30-40 cm, be flush with the ground level or located above the ground.

Features of arrangement in winter

At sub-zero temperatures, the cost of arrangement will increase, since the poured mixture must be heated for three days. Heating occurs using a heating cable embedded in a power frame. It remains inside the structure. Additionally, the following methods are used:

creating a thermos - the foundation is covered with a film and the heat generated from the reaction of cement and water is stored;
arrangement of warm formwork - steel panels that are heated using electricity;
mixing hardening and hydration accelerators into concrete.

The latter method is cheaper and is used more often.

Caring for the foundation during the hardening process

After pouring a monolithic slab, it is necessary to carry out maintenance measures. Since the slab is a finished subfloor, it should be made as level as possible. Maintenance work for “maturing” concrete:

Formwork control. Its displacement is not allowed. If detected, eliminate within an hour.
Protection from natural phenomena. A polyethylene cover is provided - this will help from wind and various precipitation.
Drying control. After 8-10 hours, the humidity should not drop below 90%. Watering the slab is carried out for 3-5 days.

Construction on such a foundation can begin after 2 days at a temperature of 25-30 degrees, after 5-7 days at a temperature of 15-20. In winter, it is better to start construction on the 10th day. The formwork can be removed approximately a week after the completion of pouring.

Important! At any stage of the construction of a building, a responsible approach must be taken. Then the constructed structure will serve for many years.

Conclusion

If you adhere to the necessary technologies and standards for installing formwork, making concrete and pouring it, and also carry out subsequent care for the “maturing” foundation, this will ensure the necessary properties of the foundation and maximum service life.

A monolithic house is stronger than all other types of buildings. Previously, only industrial facilities and high-rise buildings were built using a monolithic method; today, private individuals also use this technology to build cottages and houses.

System for calculating the mass of a monolithic concrete slab.

A house built using monolithic technology allows you to realize the most incredible design ideas into life.

And increasingly, future homeowners are thinking about how to build a monolithic house with their own hands. This kind of construction is becoming more and more popular also because a house made with your own hands using this technology is surprisingly durable. It can withstand a small earthquake, does not require much labor or expensive materials, is durable and reliable in operation. A monolithic house can be finished with anything, and the walls can be erected immediately equipped with additional insulation. Technology that uses non-removable technology allows this.

Scheme of concrete floor reinforcement.

This technology, like any other, has its advantages and disadvantages. And the advantages are very significant:

The integral solidity of the structure greatly increases the mechanical strength of the buildings. They are resistant to damage caused by ravines, earthquakes and ground shifts.
There are no so-called cold bridges, which are found in conventional buildings made of structures with seams. This makes the rooms warmer.
Monolithic construction can be carried out at any time and on any soil.
Quite fast construction.
Low financial costs.
Projects of monolithic buildings may have curvilinearity.
If perlite, sawdust, slag, expanded clay and similar substances are used in concrete solutions, then the structure will be light enough so as not to make a heavy foundation for it.
Additional insulation will not be needed during construction with a non-removable one. And at the same time, the total thickness of the wall will be less than usual;
Monolithic walls have exceptional sound insulation.
The interfloor ceiling can be made of any material.
This technology eliminates the appearance of cracks in the walls due to the uniform shrinkage of the building.

And about the disadvantages of monolithic construction - there are much fewer of them:

on the upper floors of the structures being built, it is impossible to do without a mortar pump or concrete pump;
monolithic floor slabs will require multiple labor costs, as special scaffolding is needed;
with permanent formwork, it is necessary to equip the house with supply and exhaust ventilation, otherwise humidity and its consequences cannot be avoided;
mandatory plastering to avoid possible negative consequences from its combustion - the release of toxic substances;
mandatory grounding of the entire building, since it is reinforced concrete.

Construction technology

Diagram of a monolithic concrete strip foundation with reinforcement

As is already clear from the above, the monolithic construction technology can be produced with different formworks: removable and non-removable. Both types of construction have their own nuances and features both in the construction itself and during operation.

Removable is individual for each project. Its task is to accurately repeat all the features and curves of the future structure. Plywood, wood, iron or plastic are most often used.

The distance between the walls is the width of the future wall. And it is calculated taking into account the region of construction and the thermal conductivity of the concrete mixture used. The shields are fastened with nuts, studs, and washers. To facilitate removal after pouring, corrugated tubes are placed on the threaded rods to protect them from contact with the concrete mixture.

This technology allows you to pour not only ordinary concrete into the formwork yourself, but also mixtures with lower thermal conductivity: perlite concrete, expanded clay concrete, slag concrete, sawdust concrete, aerated concrete, foam concrete, wood concrete and others. Such walls will be more vapor-permeable and warmer, but they can withstand less loads.

Very important point in monolithic construction – reinforcement. Steel or plastic reinforcing meshes are used for it, and for even greater strength a reinforcement cage is made.

You can pour concrete no more than half a meter at a time. And it is allowed to continue pouring only after it has set. Concrete must be compacted using deep vibrators, while special attention given to the corners. After the concrete has hardened, the removed formwork is placed higher, and work continues in this way until the entire structure up to the roof is poured.

Finishing and insulation of walls can be done with your own hands no earlier than 4-5 weeks, after maximum strength has been achieved. Insulation is done with mineral wool, expanded polystyrene, warm plaster or extruded polystyrene foam.

Sometimes insulation is made with your own hands using a well facade. In this case, an indentation is made from the concrete wall and a wall is laid out of brick or tile, and the indentation is filled with ecowool, expanded clay or other insulating material.

Advantages of non-removable

Diagram of a partition made of foam blocks.

The shape may vary. There are longitudinal, corner, window-sill, over-window and others. At its core, the arrangement is reminiscent of assembling structures from a children's play set.

Permanent formwork is more popular because it also serves as an insulating layer, while overall labor costs are reduced and there is no need to spend money on wall insulation.

After the foundation is equipped with a waterproofing layer, polystyrene foam formwork is installed on it, fastened with special profiles having a tongue-and-groove fastening shape, which allows concrete to be poured without leakage and without sagging at the fastening points.

Scheme of reinforcement of floor slabs.

The width of polystyrene foam can be different. And if there are a large number of them, they can be manufactured at the factory to order. The standard block width is 150 mm, with polystyrene walls of 5-7.5 cm.

This fully meets the requirements, in which the heating will have to be turned on only when it is below +5 degrees outside.

To fill permanent formwork, you cannot use warm mixtures - only ordinary concrete. The thing is that the vapor permeability of warm mixtures is significantly higher than the vapor permeability of polystyrene foam; such proximity will lead to condensation and the house will become overgrown with fungi and mold.

After erecting walls with permanent formwork, they do not need to be insulated; applying decorative plaster or siding will suffice.

Species

During the installation of the frame, boards are used. The foundation must be at least 20 cm wider than the future walls.

In application, there are several types: formwork for foundations, floors, ring walls with the ability to change the radius, tunnel formwork. Thus, any building structural element can be manufactured.

It is impossible to construct different elements in the same way. For example, foundation formwork is installed on horizontal supports and slopes; walls are made using construction locks, brackets and racks. And for floors, the formwork is laid on a structure made of supporting volumetric racks or telescopic racks.

A removable one can be built from steel, plastic and wood. If we build formwork from plywood, then it must be cut with a saw with fine teeth in order not to damage the lamination and veneer. Holes are drilled on both sides for the same reason. Plywood formwork should be stored in a dry place. In order to make removable formwork easy to remove, special fastenings are not only made for it, but also treated with a solution specially designed for this purpose.

Tools and technology

To build a house with your own hands using monolithic technology, you will need the following:

concrete mixer, mixer;
when preparing a concrete mixture manually, you will need dishes for mixing it, shovels, and measuring utensils;
a stretcher for carrying concrete mixture or a wheelbarrow;
gas cutter, construction hair dryer;
mesh for reinforcement;
scissors for cutting mesh, pliers or other similar devices;
knife for cutting polystyrene foam;
hammer, nails;
tape measure, water level;
machine for giving the mesh a special shape;
metal and wooden supports;
reinforcing hook for tying wire;
perforator;
personal protective equipment.

The monolithic technology of building a house with your own hands allows you to completely dispense with additional building materials, except for those required for making the mixture for pouring into the formwork.

In practice, several foundation designs are used in construction. One of the most common is monolithic. In essence, it is a reinforced concrete monolithic slab laid to some depth in the ground.

Its difference from other types of bases is that when lifting groundwater or deformation of soil layers, the monolith located under the building will respond to changes as a whole, that is, with its entire mass. Such a reaction will not lead to deformation of the house.

A monolithic slab can be given any shape that will completely match the shape of the house. And the most important thing is that this design of the building’s base ensures complete tightness, since there are no structural joints, and the concrete itself is made using water-repellent additives.

In addition to the obvious advantages, the monolithic design also has some disadvantages. These include the large amount of time required for its construction. To pour the slab itself, a significant amount of concrete and the use of special equipment will be required.

As already noted, a monolithic foundation is a slab laid in a previously prepared place. But, nevertheless, there are several ways to make such a base. They differ from each other in terms of hydro- and thermal insulation. As you already understand, a strip monolithic foundation is a little different. There, the earth is dug up only for the foundation, if there is no basement, and the earth remains under the space of the rooms. Here the entire volume of earth is excavated, under the entire area of the house.

The simplest of these types of foundations is performed according to the following scheme:

A reinforcement structure is installed at the bottom of the pit, on a pre-compacted sand cushion, and then filled with concrete. More complex ones include structures that use sheets of waterproofing material, geotextiles, and, depending on the type of soil, it is possible to make an additional cushion from crushed stone.

The most complex monolithic foundation looks like a multi-layer sandwich in cross-section:

sand cushion;
layer of geotextile;
layer of crushed stone;
the so-called preparatory layer of concrete;
waterproofing layer;
monolithic slab.

Sometimes, to increase the reliability of foundation protection, polystyrene sheets are laid before pouring concrete, thus improving the thermal insulation of the foundation.

Such complex structures are used on difficult soils, for example, with a high groundwater level. Builders with extensive experience say that a monolithic foundation can be used even in peat bogs.

To calculate a monolithic foundation slab you need to know:

Groundwater level;
Parameters of the soil on which the foundation will be placed;
The amount of soil freezing;
The total weight of the building, it includes the weight of the box, roof, furniture installed in it, household appliances and residents;
Size of snow and wind load;
The weight of the plate itself.

As a result of calculating the specified parameters, it is possible to determine what pressure the entire structure will exert on the ground. Then you need to refer to SNiP 2.02.01–83 and determine the maximum pressure on the ground at the building site. Let's look at an example:

The weight of the building is 19 tons;
Roof weight 3 tons;
The weight of the foundation slab is 20 tons.

Possible snow and wind loads will add 7.5 tons on top, for a total load of 49.5 tons.

With a building size of 6x6 meters, the surface area of the foundation will be 36 square meters or 360,000 square centimeters. The load on the ground will be the difference between the weight of the structure and the area of the foundation, resulting in 0.13 kg per square meter. centimeter. This load is acceptable for any soil.

When calculating the thickness of the monolith, it is imperative to take into account the following parameters:

Distance between layers of reinforcing mesh;
The height of the concrete layer on and under the outer layers of the reinforcing mesh;
Reinforcement dimensions.

Practice shows that the traditional slab thickness is 200–300 millimeters. If we take into account that under it there should be a compacted sand cushion with a total height of up to 300 mm, then the thickness of the composition is 600 mm. It is necessary to understand that this parameter changes depending on the type of soil and the weight of the building.

In addition to the power calculation of the structure, it is necessary to calculate the amount of consumables and reinforcement.

The volume of concrete is equal to the product of the perimeter of the foundation and its height, and the required volume of sand or crushed stone is calculated in the same way. Based on the calculations carried out, waterproofing, fittings, etc. will be known.

Direct construction of a monolithic foundation

Stage I. Site preparation

Preparatory work for the construction of a monolithic foundation begins with cleaning the surface of the construction site. Everything unnecessary is removed from it, including the turf on which the grass cover is located. After this, you can mark the future pit. It is advisable to start marking from the wall that will be parallel to the fence.

For marking, you will need a cord that does not stretch, several pegs. If you don’t have special geodetic tools at hand to use for marking, you can do it yourself. It is necessary to prepare several pieces of cord in advance; their length should be equal to the length of the wall and the allowance for securing it to the peg.

After you have marked the first wall using a cord and pegs driven into the ground, you need to tie the piece of cord that will mark the second wall to one of the ends. To form between them, the developer must solve the Pythagorean Theorem, this will allow us to find out the length of the diagonal between the walls.

By moving the cords you need to build a right triangle. Once it is built, you can begin marking the remaining walls. The result will be a rectangle that indicates the location of the future foundation. You can check the quality of the markup quite simply. It is necessary to measure the diagonals; if everything is marked correctly, then their sizes will coincide.

After marking is completed, excavation work begins. The main requirement for the quality of their implementation is the following - the bottom of the pit must be located strictly horizontally, look at the photo.

This determines the quality of the foundation being built. If we take into account that the depth of the pit lies within 1 meter, then the developer has a choice: to dig it manually or invite special equipment. In any case, after the main volume of soil has been removed from the pit, it is necessary to level the bottom and, as soon as it is found, remove all excess from it.

After the foundation pit is ready, it is necessary to arrange a cushion, as noted above, it can be made of sand or small crushed stone. The height of the cushion is up to 300 mm after compaction.

By the way, before you start pouring sand, it is advisable to lay geotextiles at the bottom of the pit; it will prevent sand from penetrating into the soil surface. For this operation, it is advisable to use a special vibration rammer.

As the sand compacts, it is necessary to constantly add fresh sand and continue to compact it until the desired height of the cushion is reached. The surface of the pillow should be located in a horizontal plane.

Stage III. Installation of formwork

Any work related to the manufacture of reinforced concrete structures is, in one way or another, related to the arrangement of formwork. The simplest formwork is wooden panels knocked down from boards. The boards are attached to vertical bars.

These boards must be installed vertically and secured with wooden braces resting on a peg driven into the ground. The step between them is about 1 meter. But practice shows that the more often they are driven into the ground, the stronger the formwork will be.

It is advisable to protect a full-fledged monolithic foundation from moisture and ensure its thermal insulation. To achieve waterproofing, ordinary roofing felt is used, which is laid in two layers or on the surface of the cushion if a simple monolith is being constructed, or laid before pouring on a layer of intermediate concrete.

Thermal insulation of the foundation, if necessary, is constructed from polystyrene foam. A layer of insulation is laid in front of the concrete layer and a polyethylene film is placed on top of it.

The reinforcement structure is made on a sand bed. It consists of two belts. For reinforcement, reinforcing mesh may be used, but this only applies to foundations for small structures, for example, a bathhouse.

To build a full-fledged foundation, it is advisable to use corrugated reinforcement with a diameter of 10 mm or more.

For vertical rods, it is permissible to use smooth reinforcement with a diameter of 8 mm or more. We must remember that the heavier the building, the larger the diameter of the reinforcing bars.

Vertical reinforcement is driven in in increments of 200–300 mm over the entire area to be poured with concrete. The bottom layer of reinforcement should be located at a distance of about 50 mm from the surface of the pillow, and the top layer at a distance of 50 mm from the surface of the foundation. The reinforcement is connected to each other with knitting wire or plastic clamps.

Pouring the foundation is essentially a finishing operation, and experience suggests that to carry it out, it is advisable to order concrete from the nearest plant and deliver it using a mixer. Thus, it will be possible to carry out pouring from several points, and leveling it will be much easier. By the way, you must always remember that the concrete being poured must be compacted. To do this, you can use special submersible or surface vibrators.

Video

Watch a video about building a monolithic slab foundation for a house with your own hands.

A monolithic slab or slab foundation is a fundamental foundation, which, unlike a strip foundation, has a simplified installation technology and is used for “difficult” soil. Such support is much more reliable, lasts longer and is suitable for all types of buildings (block, wooden, brick houses, one-story and multi-story buildings, bathhouses, barns and much more).

The main advantage of a slab foundation is that it can be easily erected by a person who does not have much experience in construction work. In addition, buildings of this type have other advantages.

Pros and cons of slab foundations

By and large, such a foundation is an improved version of a strip foundation with increased load-bearing capacity. The slab shallow monolith has the following advantages:

Suitable for areas where the soil is highly heaving. If the soil is mobile, then laying a strip foundation is impossible. In turn, a slab foundation on heaving soils, when the soil freezes and freezes, will rise and fall evenly without collapsing.
Exerts reduced pressure on the ground.
Not subject to deformation and shrinkage.
Requires minimal effort and earthwork when preparing the foundation (to prepare the pit, you will need to remove a very thin layer of soil).

In addition, a monolithic slab foundation can be used as a finished floor; a heating system can be immediately integrated into the base.

However, there are both pros and cons to a slab foundation. The latter include high cost building materials that will be required for such a structure. However, considering that when laying a monolithic foundation you get two in one (foundation and floor), the amounts will not differ so much.

With proper calculation of the slab base and proper placement of the layers of the “pie”, you will build a house on any soil.

Construction of a monolithic slab

As with any installation monolithic structures, the construction of a slab foundation implies a certain sequence of layers of concrete “pie”:

Sand-gravel substrate - 15-20 cm of sand allows you to level out “unruly” soil, and 15-20 cm of gravel will become a good drainage system.
Geotextile (some lay it in front of the sand base).
Concrete “preparation” about 5-10 cm thick. This layer is a rigid base that will be required for waterproofing.
Rolled waterproofing material (it is better to give preference to fiberglass-based materials).
Thermal insulation is about 15-30 cm thick. Insulation (expanded polystyrene is best) will reduce the force of heaving and make the foundation not so cold.
Armobelt consisting of two reinforcing mesh with cells measuring 20 x 20 (rod diameter 12-16 mm).
Concrete screed 20-50 cm thick and a heated floor system (if applicable).

To fill a slab foundation with your own hands, you need to make the correct calculations.

Calculation of slab foundation

Unlike a strip foundation, to calculate a slab foundation you will need to specify much fewer parameters. We will need to know the bearing capacity of the soil and the concrete itself. It is also worth making sure that the slab foundation will be able to withstand the weight of the future building. To do this, let's divide total weight structures ( concrete base and buildings) to the total area of the foundation.

Let's look at an example. Dry soil has a bearing capacity of 2 kg/cm 2 , we use concrete grade M 150 with a bearing capacity of 163 kg/cm 2 . Based on these data, it turns out that the foundation and building should not exert a pressure on the ground of more than 2 kg/cm 2.

Calculation of the thickness of the slab foundation will also depend on these indicators. Let's say you plan to build a bathhouse on 2 floors, 10 x 10 m, respectively, the base area will be 100 m2. If the thickness of the foundation is 20 cm, then its approximate weight (taking into account the armored belt) will be about 100 tons. With a building wall thickness of 25 cm, the total weight of the entire structure will increase by another 30 tons. But, there will still be furniture, equipment and people in the house. We add another 70 tons and get 300 tons. If we divide this value by 100 m2, then we get approximately 0.1 kg/cm2 - this will be the pressure exerted by the building on the ground.

Healthy! If you are planning to build a small building, for example a slab monolithic foundation for a garage, then the minimum height of the base can be 10 cm. If we are talking about residential buildings, then the minimum permissible thickness is 20 cm.

However, it is worth considering that this is only an approximate calculation. Regardless of whether you plan to build a slab monolith or strip foundation yourself, it is better to carefully study:

GOST 25100 - to understand the classification of soils;
SP 70.13330 – which talks about enclosing and load-bearing structures;
SP 28.13330 – anti-corrosion coatings for structural frames of buildings;
VSN 29-85 and 37-96 – manufacturing and design of MZF.

It must be taken into account that a slab foundation is very different from a “ribbon”, so the support area and other parameters will vary.

After drawing up the project, we begin to prepare the markings for the slab foundation with our own hands.

Features of marking for a monolithic slab

The markings for such a base have several features:

For a monolithic slab, it is enough to mark only the future building itself. Where the walls and partitions will be located can be decided later, when the base is ready.
On each side, the markings need to be made 1 meter larger than the perimeter of the future house. Such manipulation is necessary for arranging the drainage system and blind area.
If, according to your project, the building will be equipped with terraces, balconies, porches and other extensions, then these elements must be poured along with the foundation. Accordingly, the markup needs to be thought out for them as well.

To carry out the construction of a slab foundation, we suggest that you familiarize yourself with the standard technology for laying such a foundation.

Do-it-yourself foundation construction technology

Let's look at step-by-step instructions that will help you lay the foundation.

Pit preparation

The depth of the pit depends on the density of the soil rocks:

If the soil is very dense, then a depth of 50 cm will be optimal.
If the site is dominated by peat, then it is better to deepen the base by 1 m.

The bottom of the pit is leveled horizontally. If during its preparation, holes have formed in some places, then you cannot fill them with earth, only with sand. Otherwise, the slab foundation for the house may shrink.

Substrate

At this stage it is necessary to prepare a cushion for the slab foundation. To do this:

Pour washed sand without impurities into the bottom of the pit.
Compact the sand layer. If the pit is very deep, then compaction must be done in layers.

If you plan to install communications, then you need to install sewerage and water supply at this stage (gas and electricity can be installed later).
Lay down the gravel bed and compact it. Make sure that the crushed stone is distributed evenly and strictly horizontally; it is better to use a hydraulic level for this.
Place geotextiles on top of the pillow.

Formwork and insulation

To prepare formwork for a slab foundation, consider the following nuances:

The formwork is placed around the perimeter of the house, and not along the markings “with a margin” of 1 m.
For the structure, use 50 mm boards.
The formwork is set to a height that will be equal to the thickness of the monolithic slab. To level it horizontally, use cords and a level. If you do not do this, then before you make the screed, you will have to place marks on the formwork itself (with such markings you can easily make a mistake).
After this, waterproof the slab foundation. To do this, lay the material overlapping on the formwork boards.
Also at this stage, an additional layer of insulation can be laid under the waterproofing. For this, it is best to use high-strength EPS.

The next stage is the insulation of the slab foundation using sheet material (for example, XPS polystyrene foam), which must be laid in two layers. The height of both layers of insulation should be about 20 cm. The material must be laid closely.

Reinforcement and filling

To do this, the following will help you step by step instructions:

You need to knit the reinforced frame in two rows with a step of 20-25 cm. Place the bottom grid on special clamps, so that there is a distance of 5-7 cm between the waterproofing layer and the metal rods.
The second row of reinforcement (top) is laid in such a way that after you pour the concrete, the lattice “hides” in the cement by 5 cm, but no less.
Connect both layers of reinforcement with vertical drains, which must be made from the same rods.

After this, the concrete solution is poured. It is best to use the M 300 brand of composition for this.

The solution must be poured in one day - the shorter the intervals between portions of concrete, the stronger and more reliable the base will be.

The poured foundation can only be leveled according to the rule and wait until the base dries (28 days for complete hardening). It is best if the weather outside is warm and the humidity is about 80%. It is also recommended to cover the base with polyethylene and wet the concrete mass daily with water from a spray bottle.

In conclusion

Thanks to these recommendations, you can independently lay a slab foundation on a slope or on “difficult” ground. However, it is worth considering that there are many options for laying such foundations. For example, some people prefer pile-slab foundations.

It is difficult to imagine the construction of buildings without the installation of concrete floors. Reinforced concrete panels manufactured at enterprises are often used. To install them, it is necessary to use special lifting equipment. Modern technology allows you to build monolithic ceiling with your own hands without the use of lifting devices. Let us consider in detail the design features and manufacturing technology of a solid floor, which is superior in terms of a set of indicators to a structure made from standard slabs.

When building any individual two-story residential building, the question arises of how to make the interfloor ceiling

Why is a monolithic base superior to the installation of hollow core slabs?

The pouring of a monolithic floor and the technology of laying floor slabs manufactured at reinforced concrete enterprises are aimed at forming a strong reinforced concrete base that serves as the floor of the upper floor and the ceiling of the lower. However, a solid interfloor slab is superior to a prefabricated structure in a number of indicators.

The main advantages of a monolithic base:

increased safety margin associated with the absence of joining seams in a solid reinforced concrete structure;
uniform transfer of existing loads to load-bearing walls and foundations;
possibility of implementing non-standard layout and original solutions for which it is difficult to use standard slabs;
ease of implementation of design solutions related to the construction of remote balconies on a cantilever slab;
impossibility of displacement when installing a solid interfloor base in the longitudinal and transverse directions.

In houses made of brick, concrete or concrete blocks, the floors are usually made of reinforced concrete

One of the main advantages is the absence of the need to use special lifting equipment to lift massive reinforced concrete slabs, as well as the ability to carry out installation activities on your own.

How to make a floor slab with your own hands - rules for laying prefabricated slabs

Standard reinforced concrete panels are reinforced with a reinforcement cage and do not require the installation of formwork. At the same time, despite the apparent ease of implementation installation work, before starting construction activities, you should carefully familiarize yourself with the rules for installing solid slabs.

Observe the following requirements when laying panels on solid walls:

pay attention to the distance between the end planes of the load-bearing walls, which does not exceed the maximum length of the finished slab (up to 9 meters);
use lifting equipment to remove and transport slabs to the work site;
securely fasten the rigging equipment to the loops or special sling eyes built into the concrete mass;
carry out installation on the planned end plane of the walls, and you must ensure that they are evenly laid;

The most common and universal is laying factory-made floor slabs

support the reinforced concrete panels on the walls, ensuring an equal amount of overlap. The slabs should be located 90-150 mm away from the edge of the wall;
carefully seal technological gaps and butt seams cement mortar, do not allow installation without cementation;
control the horizontalness of the surface during installation using a building level and plumb line;
carry out installation only on the surface of main walls, construct internal lintels and partitions after installing the slabs;
cut openings and interfloor hatches only in the area where adjacent concrete panels are joined;
provide a guaranteed three-millimeter gap between the side planes of reinforced concrete slabs.

If the overall width of the precast panels does not match the distance between the walls, lay them with an even gap or leave gaps on the sides and then seal them with concrete blocks or mortar.

When concreting the gaps, attach a shield to the underside of the slabs to allow the mortar to be poured.

The quality of installation work depends on the correct implementation of preparatory measures.

Observe the following requirements:

ensure the flatness of the ends of the main walls, eliminate unevenness using cement mortar;
make sure that the load-bearing walls have a safety margin, strengthen them, if necessary, with a reinforced belt;
fasten the support rods in 1.5 m increments to secure the slabs during installation.

Not all work can be done independently

Perform installation using lifting equipment according to the following algorithm:

Place a layer of mortar on the end of the walls.
Sling the slab by the eyes.
Give the command to the crane operator to move the panel.
Lower the slab, maintaining a distance of at least 120 mm on each side.
Check the correct position and disconnect the straps.

Remember that horizontal installation is ensured only by a layer of concrete without using steel reinforcement and various elements as a backing. At the final stage of the work, anchor the slabs with steel reinforcement or a ring anchor. Then the joining seams should be sealed with cement mortar, and the internal cavities of the slabs on the end sides should be filled with mineral wool or cement mortar 30 cm on each side.

Calculation of the load on a monolithic floor

During operation, a monolithic floor is exposed to various loads:

permanent. They are transmitted by the mass of the building walls, internal partitions, as well as the weight of the building’s roof structure, which absorbs the additional influence of snow loads and wind;
temporary. Their size is related to the mass of engineering communications, suspended ceilings, floor finishing, furniture, as well as the number of people in the room.

Like everything related to construction, monolithic flooring begins with a project

The magnitude of the perceived load is determined by the thickness of the reinforced concrete floor. Thus, with a thickness of a monolithic slab of 20 cm, each square meter of surface can accommodate up to 0.5 tons of payload.

Correct calculations will allow you to estimate the load capacity reinforced concrete slab taking into account actual operating conditions, and also to avoid the formation of cracks.

The accuracy of calculations is influenced by a complex of factors:

overall dimensions of the ceiling;
thickness of the reinforced concrete slab;
brand of concrete used;
magnitude design load per square meter of flooring.

Calculations make it possible to determine the diameter of reinforcing bars that absorb bending and tensile loads. To perform calculations yourself, you must master the calculation methodology. When planning to build a monolithic floor with your own hands, it is advisable to entrust the calculations to professionals or use an online calculator.

How to pour a monolithic floor slab - technology for performing the work

After performing calculations and determining the parameters of the reinforced concrete slab, you should prepare building materials, as well as the necessary tools.

After the formwork is arranged, a reinforcement frame made of two meshes is installed in it

The technology for forming a solid reinforced concrete slab involves performing the following work:

Production and installation of panel formwork.
Assembly of the reinforcement frame.
Preparation of concrete solution.
Filling the formwork with concrete mixture.

Let us dwell on the features of each stage.

How to install formwork for a monolithic floor

To make a formwork structure, prepare:

moisture-resistant plywood up to 25 mm thick, covered with laminate. The smooth surface of the plywood will make it easier to remove the panels after the concrete has hardened;
planed boards made of durable types of wood. Make the lower shield from a board 50 mm thick and up to 200 mm wide;
wooden logs with a diameter of 120-150 mm or standard telescopic supports. They are designed to fix the formwork structure;
boards or beams used as transverse beams of formwork. The cross members support the prefabricated panel frame.
hardware and a standard set of tools, including a saw for cutting wood, a hammer and a building level.

The technology involves the formation of a reinforced concrete mass using the formwork method. To cover the ceiling, the formwork is installed with your own hands according to a simple algorithm.

The construction of a monolithic floor slab assumes that concrete will be poured into horizontal formwork

Procedure:

Mark the level of the formwork on the surface of the walls.
Install vertical beams, logs or supports in 1-1.2 m increments.
Secure the cross bars or metal profiles in the support forks.
Lay sheets of plywood or planed boards without gaps and secure them.
Secure the vertical walls around the perimeter of the wooden formwork.
Check the levelness of the surface and the tightness of the corner areas.

Dismantling of the formwork is carried out a month after pouring concrete.

Reinforcing reinforced concrete floors - we reinforce reinforced concrete floors with our own hands

To strengthen the overlap you should prepare:

linings for reinforcing bars. Clamps are installed to ensure a constant distance between the frame and the concrete surface;
rods with a cross section of 12-18 mm and annealed wire for tying reinforcement. A crochet hook will speed up the connection of elements.

You will need a device for bending rods, as well as a grinder with a circle for metal.

To ensure that the lower mesh is located at the required distance, special plastic clamps are placed under it

When assembling the reinforcement cage, follow the given sequence of operations:

Cut the reinforcing bars into pieces of the required sizes.
Tie the rods with wire, forming a mesh with cells 15x15 or 20x20 cm.
Place the bottom mesh on the supporting elements.
Install vertical bars in 1 m increments.
Assemble the top tier of the frame and attach it to the vertical rods.

When assembling the reinforcement cage, pay attention to the amount of overlap, which is 35-40 times greater than the cross-section of the rods.

Preparing concrete for a monolithic floor

When thinking about how to pour a monolithic floor with your own hands, determine the composition of the concrete solution to be poured.

Concrete for monolithic flooring is prepared based on the following components:

cement grade M400;
crushed stones up to 20-30 mm in size;
sifted sand;
water.

It is better to order concrete directly from the factory

The standard recipe involves mixing sand, crushed stone and cement in a ratio of 2:1:1. The amount of water added depends on the moisture content of the ingredients. Water is added until the solution reaches a creamy consistency.

It is convenient to mix in a concrete mixer. First, mix the dry ingredients and then gradually add water.

Concreting a monolith - pouring a monolithic floor on your own

To ensure the strength and uniformity of the reinforced concrete surface, it is necessary to pour a monolithic floor slab in one step. Given the increased need for concrete, it is advisable to purchase a ready-made solution delivered in a construction mixer.

Filling the floors with your own hands is carried out according to the following algorithm:

The concrete solution is fed into the formwork and distributed evenly over the entire area.
Compaction is carried out using a deep or surface vibrator.

After compaction, the surface of the massif is leveled, hardening for four weeks.

Hardening of a monolithic floor slab - taking care of concrete

The normal course of the hydration process requires periodic wetting of the concrete. When concrete hardens, a significant amount of heat is released, which promotes the evaporation of water. Lack of fluid causes cracks to appear.

It is necessary to maintain the humidity of the array as follows:

lay polyethylene on the surface;
Moisten the concrete periodically.

It is important to prevent the concrete from drying out and cracking.

Having mastered the technology of performing the work, it is not difficult to make a monolithic ceiling with your own hands. Using a proven method, it is easy to produce solid, as well as interfloor ceilings of a foam block house. When deciding, use ready-made panels or pour a monolithic reinforced concrete slab. If done correctly, it will serve as a reliable foundation for the walls of the building. Use high-quality concrete for pouring, made according to a proven recipe.

Today you can use various types of foundations for your home, but monolithic ones are especially popular. Such foundations can be made in the form of strips, support pillars, or slabs. The choice of one option or another depends on the soil on which the houses will be built.

Types of monolithic foundation

Today, monolithic foundations are made various types, all of them can be combined into 3 large groups:

strip base;
columnar base;
slab base.

All monoliths can be divided according to the following characteristics:

simple concrete structures, which are poured without reinforcement;
reinforced concrete structures, which during the construction process are reinforced with armored belts made of metal rods.

The strip base is the most popular, since the construction technology is relatively simple, the costs required are less than for a slab base, but there is the possibility of constructing a basement or ground floor. A similar foundation is used for almost any type of soil; it is excellent for wooden brick and concrete houses, and is preferable when constructing frame buildings. The structure is a concrete strip that runs along the perimeter of the building, under the load-bearing internal walls.

It consists of supports, that is, hollow pillars, which after installation are completely filled with concrete. Such foundations are reinforced with metal rods; a wooden or monolithic reinforced concrete grillage is usually placed on top.

Monolithic slab foundations are the most reliable, they can be installed even on difficult and water-saturated soils, but the costs of its construction are significant.

In addition to the consumption of concrete mixture, such a foundation takes large number reinforcement, it is knitted with special wire.

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Tape depth and width

To pour a monolithic strip foundation, specialists must make a calculation. It would seem that it could be simpler, but in fact, the depth of the tape, the width, and the need for expansion at the bottom of the sole - all this data can only be obtained by performing a calculation.

The depth depends on the type of soil and the loads on the structure. For example, for a low-rise building, a tape depth of 50 cm is sufficient. If the soil is characterized by seasonal heaving, then it is necessary to deepen the monolithic foundation to 70 cm, and most likely to the entire 1.5 m. The level of soil freezing also affects the laying depth. The lowest point of the foundation should be below the freezing level. Data to perform such a calculation can be obtained from ongoing geology. Such numbers are available in the local specialized service, and they are not so difficult to obtain.

As for the width for the tape, the load on the base and the width of the future load-bearing wall are taken into account. The optimal value is 40 cm, but if the depth of the base is significant, then it is necessary to add another 25 cm to the data obtained to ensure the reliability, stability and strength of the base.

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How to make a monolithic strip foundation: step-by-step instructions

To make a strip monolithic foundation, you must first make calculations regarding the following parameters:

width and depth of the tape, height above ground level;
area and width of the sole, the need to expand it at the bottom of the pit;
reinforcement with metal rods.

Such parameters depend on many circumstances, ranging from site conditions and soil type to climatic conditions and building loads. It is recommended to entrust the calculations to specialists, since even the slightest mistake will lead to the fact that the monolithic foundation will begin to gradually collapse, and with it the house itself.

Stages of foundation construction:

Marking is being carried out on the site. For this, the most common rope, wooden pegs, building level, tape measure and wooden square are used. The location lines of the future foundation are marked on the site.
A trench of a given depth is dug. We must try to ensure that the walls on the sides do not crumble.
When everything preparatory work will be completed, it is necessary to make a fill of sand at the bottom of the trench. Its thickness should be approximately 15-20 cm, after which the sand is moistened and compacted. The next layer will be a gravel fill, which also needs to be compacted and carefully leveled. Why do this? Such a pillow not only protects from excess moisture, but also allows you to correctly distribute loads on the ground, i.e. acts as a shock absorber.
If the design of the project involves the use of a drainage system to drain groundwater and sedimentary water, then it is necessary to start doing it right now. The bottom of the trench must also be waterproofed with molten bitumen.
After the bottom is prepared, it is necessary to make formwork for pouring. Regular edged wooden boards and moisture-resistant plywood are suitable. The formwork is a box that is open at the top; its walls must be knocked down very tightly, using galvanized nails. It is not allowed for gaps to remain or unevenness to be observed, since the strength and reliability of the entire structure depends on this.
Next, you need to make a reinforcing frame that will strengthen the monolithic base tape. No special calculation is needed for this; you just need to correctly calculate how much reinforcement is needed. This calculation is not very complicated, it takes into account the following: the armored belt is made in 2 rows, each requires 2 horizontal rods and vertical guides for rigidity. The calculation is carried out in such a way that all the rods do not reach the edges of the formwork by about 5 cm, i.e., after pouring, the reinforcement or parts of the knitting wire with which it is fastened should not remain on the surface.

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Final works

If the preparatory process is completed, then you can begin pouring the concrete mixture. You cannot interrupt the pouring process - this is a significant mistake; a monolithic foundation will not be strong. After pouring, it is necessary to compact the solution; for this purpose, a vibrating plate or an ordinary metal rod is used. This must be done so that all the air is completely removed from the mixture. If you leave everything as is, the monolithic foundation will be porous after drying.

The base is erected quite quickly, it only takes time for it to dry completely. After pouring, the monolithic foundation must be protected with plastic film; during the first days it must be moistened so that the concrete does not crack. When the mixture is completely dry, you can begin waterproofing. Upper part The tapes are covered with 2 layers of roofing felt. The last step is the strapping, which can be made from wooden beams treated with antiseptics.