Reinforcement is a construction process that is used to enhance the durability of a structure and increase its service life. It represents the formation of a prefabricated skeleton, acting as a protective component that resists the impact of soil on the walls of the structure.

To achieve maximum results, you should clearly calculate how much reinforcement is needed, as well as accurately reinforce the building’s foundation.

Correct reinforcement of a strip foundation with your own hands

At the base of the foundation, the primary component is concrete mixture, formed from cement, sifted sand and clean water. Since this solution does not have sufficient physical characteristics that can provide a guarantee against various types of deformations in the foundation of the structure, metal is additionally used.

It allows you to increase the degree of resistance to base shifts, sudden temperature changes and other negatively affecting factors. The metal itself is plastic, but it is capable of providing decent fixation, so reinforcement is an important and necessary process in the entire construction complex.

Reinforcement should be carried out only in places where there is a high degree of vulnerability to tension. Most often it occurs on the surface, so it is imperative to reinforce the upper level of the base. In order to avoid corrosion of the material, it should be protected with a layer of concrete mortar.

The acceptable distance of the reinforcing belt from the surface should be about 5 cm.

Possible deformation zones:

• the lower part, when there is a downward bending of its middle;
• the upper part is the arching of the frame upward.

For the middle level of the base, reinforcement is not necessary, since there is practically no tension in this zone.

Taking into account possible deformation options, it is imperative to reinforce the bottom and top using reinforcement with a ribbed surface and a diameter in the range of 10–12 mm. In this option, the closest contact with the concrete solution is observed. Other skeletal elements may be small in diameter and have a smooth surface.

If a foundation with a width of up to 40 cm is being reinforced, 4 reinforcement rods with a diameter of 10–16 mm are used, which are connected into a frame with a diameter of 8 mm.

The long-length tape type of base has a relatively small width, which is why it can only contain longitudinal stretches without transverse ones. Therefore, in this situation, it is best to use smooth and thin rods to form a frame, and not to carry heavy loads on the base.

Most attention should be paid to the reinforcement of corners, since in many cases deformations occur in this part of the structure. Reinforcement of the corners of the structure must be carried out so that one of the ends of the bent metal goes into one wall, and the other into another. Since not every reinforcement material can be welded, it is better to fasten the elements together using wire.

Rules for correct reinforcement of a strip foundation:

1. The work begins with the installation of formwork, which is lined with parchment on the inside. This procedure allows you to quickly disassemble the created structure in the future.
2. Then you should drive the reinforcing bars into the ground trenches at a distance of 5 cm from the formwork and in increments of 40–60 cm. The length of the rods should be equal to the depth of the foundation.
3. A stand measuring 8–10 cm is placed at the bottom of the trench, and 2 or 3 threads of a row of reinforcement are formed on top of it. As a stand, you can use an ordinary brick laid on its edge.
4. Upper and lower chord made of reinforcement with cross connections attached to vertical rods.
5. In places where elements intersect, it is necessary to fasten with wire or welding.

Be sure to maintain the distance to the future surface of the foundation; you can use bricks for this.

1. Installing the fittings, ventilation holes should be made and concrete should be poured.

The presence of ventilation holes and holes increases shock absorption and prevents the occurrence of rot.

The ideal option is to use a circuit for strip foundation, consisting of primitive geometric shapes, such as a square or rectangle, then the frame is easier to mount correctly, and the resulting foundation is more reliable and strong.

Basic mistakes in reinforcing strip foundations

The most famous and frequently made mistakes:

It is forbidden to close the vents for the winter, as this leads to a lack of ventilation and rotting of the structure.

Why do you need reinforcement in a strip foundation?

Over time, any house will experience subsidence, as the soil under the base yields to pressure from above and becomes compacted. The more pressure is put on it, the stronger and faster it compacts. If the resulting pressure is distributed evenly over the entire area of ​​the strip foundation, then this is not a particular problem.

As a rule, in real conditions the pressure on the foundation is not symmetrical, which is why the building settles unevenly. To avoid such a problem, tapes of various widths are used in the foundation, but even this technique does not always help eliminate and equalize the pressure on the foundation.

Uneven settlement of the foundation is caused by:

1. Various soil inclusions.
2. Uneven and inconsistent humidity.
3. Various additions and extensions.
4. Leakage of water-carrying communications.
5. Absence of a blind area on any side, etc.

Under the influence of these causes of settlement, the soil surface under the foundation becomes curved relative to the vertical direction of the building. The corners of the structure and areas with large load differences are most affected.

In such a situation, internal tension arises in the foundation strip, which contributes to the occurrence of bending moments and cracks. To eliminate unwanted pressure on the foundation and reduce the number of cracks and bends, reinforcement is added inside the foundation.

What reinforcement is needed for the foundation?

There are two options used in the construction of reinforcement:

1. Steel, which is divided into:
   • core;
   • wire
2. Composite reinforcement. It is used relatively rarely due to its characteristic disadvantages.

To reinforce a strip-type foundation, rod reinforcement is used as the main (working) material and smooth reinforcement as an additional one.

The main property for working reinforcement is the ability to quickly and well adhere to concrete. This type of reinforcement is produced with a periodic profile, dividing it into classes according to strength indicators.

According to GOST, which existed during the USSR period, for private types of construction, class A-ΙΙΙ reinforcement or an analogue of A400 (according to modern GOST) is used. For transverse reinforcement, a smooth rod of class A-Ι or A240 (modern GOST) is used.

There is a difference between the old and modern fittings in the form of a modified crescent-shaped profile; in other aspects there are no differences.

To choose the right reinforcement for the foundation in the store, you just need to pay attention to the designations:

• Index C indicates that the reinforcing bars are weldable;
• Index K indicates that the reinforcement is resistant to corrosion cracking processes that arise due to pressure on the foundation.

If these indices are not on the packaging, it is better not to buy such similar material.

Structural requirements for strip foundations and their reinforcement

Due to the inability to accurately calculate the diameter for a strip foundation, special design requirements for its reinforcement were developed:

How much reinforcement is needed for a strip foundation?

For the foundation, reinforcement with a small diameter is used, for example, for low-rise construction reinforcement with a diameter of 10–12 mm is used, somewhat less often – 14 mm.

Regardless of the height of the base for reinforcement, you will need to make two belts of class A3 ribbed reinforcement at a distance of 5 cm from the bottom and top of the foundation. Transverse and vertical rods can be made of smooth type A1 class reinforcement.

For a foundation width of about 40 cm, it is sufficient to use 4 longitudinal reinforcement bars, of which two are located at the bottom and two at the top. If the width of the foundation is more than 40 cm or construction is carried out on moving soils, more rods should be used, approximately 3 - 4 for the upper and the same number for the lower chord.

To calculate the amount of required reinforcement, there are two methods:

Self-calculation

Example. The length of the foundation for a 6 by 10 m building with two walls will be 48 meters (6+10+6+10+6+10=48m).

If the width of the base is 60 cm, and the reinforcement consists of 6 longitudinal rods, then their length will be 288 meters (6*48=248m).

The step between the transverse and vertical rods is maintained at 0.5 m, the width of the foundation is 60 cm, the height is 1.9 m, the distances of the rods from the frame are 5 cm.

In this case, the length of smooth reinforcement with a diameter of 6 mm for each connection is 640 cm or 6.4 m ((60-5-5)*2+(190-5-5)*3=640 cm), and the connections will be 97 pieces (48/0.5+1=97 pieces), they will require 620.8 meters of reinforcement (97*6.4=620.8 m).

Each connection requires 6 crossings for tying reinforcement and approximately 12 pieces of tying wire. One bundle requires 30 cm of wire. Based on these data, total consumption wire will be 349.2 m (0.3*12*97=349.2 m).

Use of reinforcement factor

For buildings with a small number of storeys, there is an indicator for the amount of reinforcement already established by the builders, which is 80 kg/m3.

Example. If 20 m3 of concrete solution is needed for the foundation, then 20*80=1600 kg of reinforcement will be needed. Calculating concrete is not difficult, you just need to know the perimeter of the house, the length of the internal walls, set the height of the tape to 30 cm and multiply it by the width.

To make the calculation more economical, it is best to make a more accurate calculation of the required amount of reinforcement by drawing a reinforcement diagram. And then, having calculated the moldings for longitudinal and transverse reinforcement, vut, and also adding to this approximately 10%, which will be spent on trimmings, multiply the result by the weight of a linear meter for each of the reinforcement diameters used.

Reinforcement of a strip foundation - knit or weld?

Metal rods can be connected to each other into a frame by knitting or welding. Each option has its own positive and negative qualities.

The main disadvantage of welding is the inability to make a high-quality transverse connection using a hand electrode. In factories, frames and meshes are connected using contact rather than arc welding.

In this regard, insufficiently strong connections (lack of penetration) or weakening of the longitudinal rod (undercut) are very often observed. Also, a big disadvantage of welding is that not all materials can be welded, for example, class A3 reinforcement is made from 35GS steel, which cannot be welded.

Also, if you take into account that welding requires the apparatus itself, knowledge, the ability to use it, as well as electricity consumption, then knitting is given more advantages in construction.

Knitting is carried out using wire with a diameter of 0.8–3 mm, and a special crochet hook is used as a tool. The only drawback of this connection option is its high labor intensity.

What materials are used for reinforcement?

The following materials are required for reinforcement:

1. Steel or composite reinforcement, the rods of which are made of fiberglass or metal.
2. Clamping tool(crochet hook).
3. Steel wire(tightening clamps) for knitting. For metal with index C, welding can be used. In this case, a welding machine is required.
4. Hacksaw for metal etc.

Proper reinforcement of a strip foundation will strengthen the building for many years, reduce the number of cracks in the foundation and walls, and also protect the structure from settlement.

Reinforcement of a strip foundation significantly increases its strength characteristics and allows you to create stable structures while reducing weight.

Calculations of reinforcement and reinforcement schemes are carried out in accordance with the provisions of the current SNiP 52-01-2003. The document has detailed requirements for calculations, provides footnotes to regulatory documents and codes of practice.

SP 63.13330.2012 Concrete and reinforced concrete structures. Basic provisions. Updated version of SNiP 52-01-2003. File for download

The strip foundation must meet the requirements for durability, reliability, resistance to various climatic factors and mechanical loads.

The main characteristics of the strength of concrete structures are the resistance to axial compression (Rb,n), tensile strength (Rbt,n) and transverse fracture. Depending on the normative standard indicators of concrete, its specific brand and class are selected. Taking into account the responsibility of the design, reliability correction factors can be used, which range from 1.0 to 1.5.

Requirements for fittings

During the reinforcement of strip foundations, the type and controlled values ​​of the quality of the reinforcement are established. The standards allow for the use of hot-rolled construction reinforcement of periodic profile, heat-treated reinforcement or mechanically strengthened reinforcement.

The class of reinforcement is selected taking into account the guaranteed value of the yield strength at maximum loads. In addition to tensile characteristics, ductility, corrosion resistance, weldability, resistance to negative temperatures, relaxation resistance and permissible elongation before the onset of destructive processes are standardized.

Table of reinforcement classes and steel grades

Profile type	Class	Diameter, mm	steel grade
Smooth profile	A1 (A240)	6-40	St3kp, St3ps, St3sp
Periodic profile	A2 (A300)	10-40, 40-80	St5sp, St5ps, 18G2S
Periodic profile	A3 (A400)	6-40, 6-22	35GS, 35G2S, 32G2Rps
Periodic profile	A4 (A600)	10-18 (6-8), 10-32 (36-40)	80С, 20ХГ2Ц
Periodic profile	A5 (A800)	10-32 (6-8), (36-40)	23Х2Г2Т
Periodic profile	A6 (A1000)	10-22	22Х2Г2АУ, 22Х2Г2Р

The calculation of the strip foundation is carried out in accordance with the recommendations of GOST 27751, the indicators of limiting loaded states are calculated by group.

The first group includes conditions that lead to complete unsuitability of the foundation, the second group includes conditions that lead to partial loss of stability, complicating the normal and safe operation of buildings. According to the maximum permissible states of the second group, the following are produced:

• calculations for the appearance of primary cracks on the surface of a strip foundation;
• calculations based on the time period of increase in cracks formed in concrete structures;
• calculations of linear deformations of strip foundations.

The main indicators for resistance to deformation and strength of building reinforcement include maximum tensile or compressive strength, determined in laboratory conditions on special test benches. Technology and test methods are prescribed in state standards. In some cases, the manufacturer may use regulatory and technical documentation developed by the enterprise. At the same time, regulatory and technical documentation must be approved by regulatory authorities.

For concrete structures, these values ​​may be limited by the maximum rates of change in concrete linearity. Actual diagrams of the state of reinforcement under short-term one-sided exposure to design standard loads are taken as generalized indicators. The nature of the state diagrams of building reinforcement is established taking into account its specific type and brand. During the engineering calculation of a reinforced foundation, the state diagram is determined after replacing the standard indicators with actual ones.

Reinforcement requirements

Reinforcement cage - photo

1. Requirements for the dimensions of reinforced concrete structures. The geometric dimensions of the foundation should not interfere with the correct spatial placement of reinforcement.
2. The protective layer must provide joint resistance to the loads of reinforcement and concrete, protect against the influence of the external environment and ensure the stability of the structure.
3. The minimum distance between individual reinforcement bars should guarantee its joint work with concrete, allow for correct joining and ensure correct technological pouring of concrete.

For reinforcement, only high-quality reinforcement can be used; mesh knitting is carried out taking into account the calculated design parameters. Deviations from the values ​​cannot exceed the tolerance fields regulated by SNiP 3.03.01. Special construction measures must ensure reliable fixation of the reinforcing mesh in accordance with existing rules.

SNiP 3.03.01-87. Load-bearing and enclosing structures. Building regulations. File for download

When bending reinforcement, you need to use special devices; the minimum bending radius depends on the diameter and specific physical characteristics of the building reinforcement.

Prices for reinforcing mesh

reinforcement mesh

Video – Manual machine for bending reinforcement, video instructions

Video - How to bend reinforcement. Working on a homemade machine

The reinforcement is inserted into the formwork; the manufacture of the formwork should be carried out taking into account the requirements of GOST 25781 and GOST 23478.

STEEL MOLDS FOR THE PRODUCTION OF REINFORCED CONCRETE PRODUCTS. Technical conditions. File for download

Formwork for the construction of monolithic concrete and reinforced concrete structures. Classification and general technical requirements

Calculation of the quantity and diameter of reinforcement

For strip foundations of baths, construction reinforcement with a periodic profile Ø 6÷12 mm is used.

Current state regulations regulate the minimum number of rods in concrete to give it maximum strength characteristics. The minimum total cross-section of longitudinal reinforcement bars cannot be ≤ 0.1% of the cross-sectional area of ​​the foundation strip. For example, if the strip foundation has a cross-section of 12000×500 mm (sectional area is 600000 mm2), then the total area of ​​all longitudinal rods must be at least 600000×0.01% = 600 mm2. In practice, developers rarely maintain this indicator; the weight of the bathhouse, the nature of the soil and the specific brand of concrete are also taken into account. This calculated value can be considered approximate; deviations from the recommended values ​​should not exceed ≈20% downwards.

To calculate the amount of reinforcement, you need to know the cross-sectional area of ​​the foundation strip and the cross-sectional area of ​​the reinforcing bar. To make the calculations easier, we present to your attention a ready-made table.

	Number of rods
Diameter, mm	1	2	3	4	5	6	7	8	9
6	28,3	57	85	113	141	170	198	226	254
8	50,3	101	151	201	251	302	352	402	453
10	76,5	157	236	314	393	471	550	628	707
12	113	226	339	452	565	679	792	905	1018
14	154	308	462	616	769	923	1077	11231	1385
16	201	402	603	804	1005	1206	1407	1608	1810
18	254,5	509	763	1018	1272	1527	1781	2036	2290
20	314,2	628	942	1256	1571	1885	2199	2513	2828

Now calculations are greatly simplified. For example, to reinforce a strip foundation you use eight rows of reinforcement with a diameter of 10 mm. According to the table, the total area of ​​the rods is 628 mm. Such a frame can work with a concrete strip 120 cm deep and 50 cm wide. A few extra square millimeters can be ignored; they will be additional insurance in case of violation of the knitting technology or production of low-quality concrete.

In addition to these indicators, you need to decide on the diameters of the rods for the foundations. These indicators depend on many components; for simplified calculations, you can use the proposed table.

Using this table, you can easily select the recommended reinforcement diameter for a strip foundation.

Rules for reinforcing strip foundations

There are several patterns for tying reinforcement; each developer can use the one that is most convenient for himself. The choice of scheme must be made taking into account the size of the foundation and its load-bearing characteristics.

The reinforcement can be knitted separately, and then the finished structural elements are lowered into the foundation trench and connected to each other, or they can be knitted directly in the trench. Both methods are almost equivalent, but there is a slight difference. On the ground, all the main straight elements can be done independently; when working in a trench, an assistant is required. To knit, you need to make a special hook; the connection is made with soft wire with a diameter of ≈0.5 mm.

In some articles you can find advice to use a hand-held electric drill while knitting - do not pay attention to them. This can be written by those who have no idea about work.

Firstly, a drill will tire your hand much more and faster than a light hook. Secondly, cables will always get tangled under your feet, cling to the ends of the fittings, etc. Thirdly, not all construction sites have electrical energy. And, fourthly, your wire knots will always be either loose or torn.

For tying reinforcement, thin soft wire is used, but it has low strength. Stretch the wire well; strong tying should occur within two to three turns of the hook. Otherwise, labor productivity decreases significantly and fatigue increases. There are also options for welding reinforcement, we will talk about them in the next section of the article.

Prices for knitting wire

knitting wire

How to knit reinforcement mesh yourself

We have already said above that in this way you can knit reinforcement on the ground. Only straight sections of the mesh are made, the corners are tied after they are lowered into the trench.

Step 1. Prepare pieces of reinforcement. The standard length of the rods is six meters; if possible, there is no need to touch them. If you are afraid that such dina will be difficult to work with, cut them in half.

We advise you to start knitting reinforcement for the shortest section of the strip foundation; this will give you the opportunity to gain a little experience and be more confident in handling long rods. It is not recommended to cut them; this increases metal consumption and reduces the strength of the foundation. Let's consider the dimensions of the blanks using the example of a strip foundation 120 cm high and 40 cm wide.

The reinforcement must be filled with concrete on all sides with a thickness of at least 5 centimeters. These are the initial conditions. Taking into account such indicators, the net dimensions of the reinforcement frame should be no more than 110 cm in height (minus 5 cm on each side) and 30 cm in width (minus 5 cm on each side). To knit, you need to add two centimeters on each side for the overlap. This means that the blanks for horizontal jumpers should have a length of 34 cm, the blanks for vertical jumpers should have a length of 144 cm. But you shouldn’t make the frame so high, it’s enough to have a height of 80 cm.

Step 2. Choose a flat area, lay two long rods, and trim their ends.

Step 3. At a distance of ≈ 20 cm from the ends, tie horizontal spacers on both extreme sides. For knitting you need a wire approximately 20 centimeters long. Fold it in half, slide it under the tying point and tighten the wire with the usual twist of a crochet hook. Do not overdo it with force, the wire may not withstand it. The amount of twisting force is determined experimentally.

Step 3. At a distance of approximately 50 centimeters, tie all the remaining horizontal struts one by one. Everything is ready - set the structure aside in a free space and make another frame element in the same way. You have the top and bottom parts, now you need to fasten them together.

Step 4. Next, you should adapt stops for two parts of the mesh; you can rest them on any object. The main thing is that the connected elements occupy a stable lateral position; the distance between them should be equal to the height of the knitted reinforcement.

Step 5. Attach two vertical spacers at the ends; you already know the dimensions. When the frame begins to more or less resemble the finished product, tie all the other pieces. Take your time and check all sizes. Even though your pieces are the same length, checking the dimensions won't hurt.

Step 6. Using the same algorithm, you need to connect all the straight sections of the frame on the ground.

Step 7 Place pads at least five centimeters high at the bottom of the foundation trench; the lower mesh bars will lie on them. Place side supports and set the net in the correct position.

Reinforcement (frame installed in formwork)

Step 8 Take measurements of unknitted corners and joints, prepare pieces of reinforcement to connect the frame into a single structure. Keep in mind that the overlap of the ends of the reinforcement must be at least fifty bar diameters.

Step 9 Tie the bottom turn, then the vertical posts and the top one to them. Check the reinforcement distance to all formwork surfaces.

The reinforcement is ready, you can start pouring the foundation with concrete.

Knitting reinforcement using a special device

To make the device, you will need several boards approximately 20 mm thick; the quality of the lumber can be arbitrary. Making a template is not difficult, and it will simplify the work significantly.

Step 1. Cut four boards along the length of the reinforcement, connect them two at a time at the spacing of the vertical posts. You should end up with two identical templates. Carefully ensure that the markings of the distance between the slats are the same, otherwise there will be no vertical position of the connecting elements.

Step 2. Make two vertical supports; the height of the supports should correspond to the height of the reinforcing mesh. The supports must have side corner stops to prevent them from tipping over. All knitting work must be carried out on a level surface. Check the stability of the assembled device and eliminate the possibility of it tipping over during work.

Step 3. Place the legs of the stops on two knocked down boards, place the two upper boards on the top shelf of the stops. Fix their position in any way.

You have now created a model of the reinforcement mesh; now the work can be done quickly and without outside help. Install the prepared vertical reinforcement struts at the marked places; first, use nails to temporarily fix their position. Place a reinforcement bar on each horizontal metal jumper. This operation should be repeated on all sides of the frame. Check their position again. That's right - take the wire and hook and start knitting. It is advisable to make the device if you have many identical sections of mesh made of reinforcement.

Video - How to knit reinforcement using a device

How to knit reinforced mesh in a trench

Working in a trench is much more difficult due to cramped conditions. You need to think carefully about the knitting pattern of individual elements so that you don’t have to crawl between the reinforcement bars later. In addition, you won’t be able to knit the mesh yourself; you need to work with an assistant.

Step 1. Place stones or bricks at least five centimeters high at the bottom of the trench; they will lift the metal from the ground and allow the concrete to cover the reinforcement on all sides. The distance between the stones should be equal to the width of the mesh.

In the photo - a retainer for the reinforced frame

Step 2. Longitudinal rods must be placed on the stones. Horizontal and vertical rods should already be cut to size, as we have already told you how to measure them.

Step 3. Start forming the skeleton of the frame on one side of the foundation. If you first tie horizontal struts to the lying rods, the work will be easier. An assistant must hold the ends of the rods until they are locked in the desired position.

Step 4. Continue knitting the reinforcement one by one, the distance between the spacers should be approximately fifty centimeters.

Step 5. Using the same algorithm, tie the reinforcement on all straight sections of the foundation tape.

Step 6. Check the dimensions and spatial position of the frame; if necessary, you need to correct the position and prevent metal parts from touching the formwork.

Step 7 Now it's time to work on the corners of the foundation. The picture shows a rather complex version of knitting in the corners, you can come up with an easier one for yourself. The main thing is to maintain the length of the overlaps. And one more note. In corners, the foundation works not only for bending, but also for vertical discontinuity. These forces hold the vertical bars of construction reinforcement; do not forget to install them. To guarantee, reinforcement with a larger diameter can be used for these purposes.

You need to know that any welding worsens the physical characteristics of the strength of the reinforcement; this method should be used only in extreme cases.

If you still have to use welding, then do everything possible to put a minimum number of seams in one place, shift the fixation step of the horizontal and vertical stops by a few centimeters. During welding, accurately maintain the optimal current strength and electrode diameter. The metal in the places where the seam is applied should not overheat.

Welding reinforcement – ​​photo

And the most important thing is that only special fittings are suitable for welding; brands of such fittings are designated by the letter “C”. By the way, this fittings are significantly more expensive than ordinary ones.

There are several ways in which you can speed up and facilitate the knitting process and at the same time improve the quality of the design and reduce material consumption.

For spacers, bend the reinforcement into a “P” shape. To do this, you can make a basic machine in a couple of hours, and it will be useful not only for bending rods. First you need to bend one sample, check its dimensions and only then, using the sample as a template, prepare all the connections. Such spacers are much easier to knit; they immediately hold the desired size of the structure. Another plus is that the consumption of expensive material is reduced. At first glance, the savings seem insignificant, a maximum of ten centimeters per connection. But if you multiply ten centimeters by the number of pieces and the price of the fittings, you get a very “pleasant” amount.

For spacers, you can use reinforcement of a smaller diameter and not necessarily expensive construction reinforcement of a periodic profile. Even metal rods or wire rod of the appropriate diameter will do.

If you do not have any experience in performing such work, then it is better not to do it yourself. Having an assistant makes the process much easier and safer.

The price of a reinforced foundation is much more expensive than an ordinary one; use this method of strengthening architectural structures in extreme cases. There are many cheaper ways to increase the load-bearing characteristics of a strip foundation. True, they cannot always be used; it all depends on the specifics of the bathhouse design, the characteristics of the soil and landscape.

A few words can be said about preloaded reinforcement. This is a complex method that allows you to significantly improve all the indicators of a strip foundation without increasing the amount of reinforcement. The essence of the method is to preload the rods with forces opposite to those that will act on the structure during operation of the foundation. For example, if the rod will work in tension, then it is pre-compressed, etc.

Video - Reinforcement of shallow monolithic strip foundations

Video - Do-it-yourself foundation reinforcement

The strip foundation has a non-standard geometry: its length is tens of times greater than its depth and width. Due to this design, almost all loads are distributed along the belt. A concrete stone cannot compensate for these loads on its own: its bending strength is not enough. To give a structure increased strength, not just concrete is used, but reinforced concrete - this is a concrete stone with steel elements located inside - steel reinforcement. The process of laying metal is called strip foundation reinforcement. It’s not difficult to do it with your own hands, the calculations are elementary, the diagrams are known.

The quantity, location, diameters and type of reinforcement - all this must be specified in the project. These parameters depend on many factors: both on the geological situation on the site and on the mass of the building being constructed. If you want to have a guaranteed strong foundation, you need a project. On the other hand, if you are building a small building, you can try, based on general recommendations, to do everything yourself, including designing a reinforcement scheme.

Reinforcement scheme

The location of the reinforcement in the strip foundation in cross section is a rectangle. And there is a simple explanation for this: this scheme works best.

Reinforcement of a strip foundation with a strip height of no more than 60-70 cm

There are two main forces acting on the strip foundation: heaving forces press from below during frost, and the load from the house from above. The middle of the tape is almost not loaded. To compensate for the action of these two forces, two belts of working reinforcement are usually made: above and below. For shallow and medium deep foundations (up to 100 cm deep) this is enough. For deep belts, 3 belts are already required: too high a height requires reinforcement.

To ensure that the working fittings are in the right place, they are secured in a certain way. And they do this using thinner steel rods. They do not participate in the work, they only hold the working reinforcement in a certain position - they create a structure, which is why this type of reinforcement is called structural.

As can be seen in the strip foundation reinforcement diagram, the longitudinal reinforcement bars (working) are tied with horizontal and vertical supports. They are often made in the form of a closed loop - a clamp. It’s easier and faster to work with them, and the design is more reliable.

What fittings are needed

For strip foundations, two types of rods are used. For longitudinal ones that bear the main load, class AII or AIII is required. Moreover, the profile is necessarily ribbed: it adheres better to concrete and transfers load normally. For structural lintels, cheaper reinforcement is used: smooth first class AI, 6-8 mm thick.

Recently, fiberglass reinforcement has appeared on the market. According to manufacturers, it has better strength characteristics and is more durable. But many designers do not recommend using it in the foundations of residential buildings. According to the standards, it must be reinforced concrete. The characteristics of this material have long been known and calculated; special reinforcement profiles have been developed that ensure that metal and concrete are combined into a single monolithic structure.

How concrete will behave when paired with fiberglass, how firmly such reinforcement will adhere to concrete, how successfully this pair will resist loads - all this is unknown and has not been studied. If you want to experiment, please use fiberglass. No - take iron fittings.

Do-it-yourself calculation of strip foundation reinforcement

Any construction work is regulated by GOSTs or SNiPs. Reinforcement is no exception. It is regulated by SNiP 52-01-2003 “Concrete and reinforced concrete structures”. This document specifies the minimum amount of reinforcement required: it must be at least 0.1% of the cross-sectional area of ​​the foundation.

Determination of reinforcement thickness

Since the strip foundation in section has the shape of a rectangle, the cross-sectional area is found by multiplying the lengths of its sides. If the tape has a depth of 80 cm and a width of 30 cm, then the area will be 80 cm * 30 cm = 2400 cm 2.

Now you need to find the total area of ​​the reinforcement. According to SNiP it should be at least 0.1%. For this example it is 2.8 cm 2. Now, using the selection method, we will determine the diameter of the rods and their number.

Quotes from SNiP that relate to reinforcement (to enlarge the picture, right-click on it)

For example, we plan to use reinforcement with a diameter of 12 mm. Its cross-sectional area is 1.13 cm 2 (calculated using the formula for the area of ​​a circle). It turns out that in order to provide recommendations (2.8 cm 2), we will need three rods (or they also say “threads”), since two are clearly not enough: 1.13 * 3 = 3.39 cm 2, and this is more than 2.8 cm 2, which are recommended by SNiP. But it will not be possible to divide three threads into two belts, and the load on both sides will be significant. Therefore, they stack four, laying a solid margin of safety.

In order not to bury extra money in the ground, you can try to reduce the diameter of the reinforcement: calculate it at 10 mm. The area of ​​this rod is 0.79 cm 2. If we multiply by 4 (the minimum number of working reinforcement bars for a strip frame), we get 3.16 cm 2, which is also enough with a margin. So for this option For strip foundations, class II ribbed reinforcement with a diameter of 10 mm can be used.

Reinforcement of a strip foundation for a cottage is carried out using rods with different types of profiles

Installation step

There are also methods and formulas for all these parameters. But for small buildings it’s simpler. According to the recommendations of the standard, the distance between horizontal branches should not be more than 40 cm. This parameter is used as a guide.

How to determine at what distance to lay reinforcement? To prevent steel from corroding, it must be embedded in concrete. The minimum distance from the edge is 5 cm. Based on this, the distance between the rods is calculated: both vertically and horizontally it is 10 cm less than the dimensions of the tape. If the width of the foundation is 45 cm, it turns out that between the two threads there will be a distance of 35 cm (45 cm - 10 cm = 35 cm), which corresponds to the standard (less than 40 cm).

The reinforcement step of a strip foundation is the distance between two longitudinal bars

If our tape is 80*30 cm, then the longitudinal reinforcement is located one from the other at a distance of 20 cm (30 cm - 10 cm). Since medium-level foundations (up to 80 cm in height) require two reinforcement belts, one belt from the other is located at a height of 70 cm (80 cm - 10 cm).

Now about how often to install jumpers. This standard is also in SNiP: the installation step of vertical and horizontal dressings should be no more than 300 mm.

All. We calculated the reinforcement of the strip foundation with our own hands. But keep in mind that neither the mass of the house nor the geological conditions were taken into account. We relied on the fact that these parameters were based on .

Corner reinforcement

In the design of a strip foundation, the weakest point is the corners and the junction of the walls. In these places loads from different walls are combined. In order for them to be successfully redistributed, the reinforcement must be properly tied. Simply connect it incorrectly: this method will not ensure load transfer. As a result, after some time, cracks will appear in the strip foundation.

The correct scheme for reinforcing corners: either bends are used - L-shaped clamps, or longitudinal threads are made 60-70 cm longer and bent around the corner

To avoid this situation, when reinforcing corners, special schemes are used: the rod is bent from one side to the other. This “overlap” should be at least 60-70 cm. If the length of the longitudinal rod is not enough to bend, use L-shaped clamps with sides also at least 60-70 cm. Schemes of their location and fastening of the reinforcement are shown in the photo below.

The abutments of piers are reinforced using the same principle. It is also advisable to take the reinforcement with a reserve and bend it. It is also possible to use L-shaped clamps.

Reinforcement diagram for adjacent walls in a strip foundation (to enlarge the picture, right-click on it)

Please note: in both cases, in the corners, the installation step of the transverse jumpers is reduced by half. In these places they already become workers - they participate in the redistribution of the load.

Reinforcement of the base of a strip foundation

On soils with not very high bearing capacity, on heaving soils or under heavy houses, strip foundations are often made with a sole. It transfers the load to a larger area, which gives greater stability to the foundation and reduces the amount of subsidence.

To prevent the sole from falling apart under pressure, it also needs to be reinforced. The figure shows two options: one and two belts of longitudinal reinforcement. If the soils are complex, with a strong tendency to winter baking, then two belts can be laid. For normal and medium-heaving soils, one is enough.

Reinforcement rods laid lengthwise are working. They, as for the tape, are taken in second or third class. They are located at a distance of 200-300 mm from each other. They are connected using short pieces of rod.

Two methods of reinforcing the base of a strip foundation: on the left for foundations with normal bearing capacity, on the right for not very reliable soils

If the sole is not wide (rigid design), then the transverse segments are structural and do not participate in load distribution. Then they are made with a diameter of 6-8 mm, bent at the ends so that they cover the outer rods. They are tied to everyone using a binding wire.

If the sole is wide (flexible), the transverse reinforcement in the sole is also working. She resists the soil’s attempts to “collapse” her. Therefore, in this version, the soles use ribbed reinforcement of the same diameter and class as the longitudinal one.

How much rod do you need?

Having developed a strip foundation reinforcement scheme, you know how many longitudinal elements you need. They are laid around the entire perimeter and under the walls. The length of the tape will be the length of one reinforcement rod. By multiplying it by the number of threads, you get the required length of the working reinforcement. Then add 20% to the resulting figure - a margin for joints and overlaps. This is how much in meters you will need working reinforcement.

Now you need to calculate the amount of structural reinforcement. Calculate how many crossbars there should be: divide the length of the tape by the installation pitch (300 mm or 0.3 m, if you follow the recommendations of SNiP). Then you calculate how much it takes to make one lintel (add the width of the reinforcement cage with the height and double it). Multiply the resulting figure by the number of jumpers. You also add 20% to the result (for connections). This will be the amount of structural reinforcement to reinforce the strip foundation.

Using a similar principle, you calculate the amount needed to reinforce the sole. Putting everything together, you will find out how much reinforcement is needed for the foundation.

Technologies for assembling reinforcement for strip foundations

Do-it-yourself reinforcement of the strip foundation begins after installation. There are two options:

Both options are imperfect and everyone decides how it will be easier for him. When working directly in a trench, you need to know the procedure:

• The longitudinal rods of the lower reinforced belt are laid first. They need to be raised 5 cm from the edge of the concrete. It is better to use special legs for this, but pieces of bricks are popular among developers. The reinforcement is also 5 cm away from the formwork walls.
• Using transverse pieces of structural reinforcement or molded contours, they are fixed at the required distance using tying wire and a hook or a tying gun.
• Then there are two options:
  • If contours formed in the form of rectangles were used, the upper belt is immediately tied to them at the top.
  • If during installation you use cut pieces for crossbars and vertical posts, then the next step is tying up the vertical posts. After they are all tied, a second belt of longitudinal reinforcement is tied.

There is another technology for reinforcing strip foundations. The frame turns out to be rigid, but there is a large consumption of rods for the vertical posts: they are driven into the ground.

The second technology for reinforcing a strip foundation is to first drive in vertical posts, tie longitudinal threads to them, and then connect everything with transverse ones

• First, vertical posts are driven in at the corners of the tape and at the junction of horizontal rods. The racks should have a large diameter of 16-20 mm. They are placed at a distance of at least 5 cm from the edge of the formwork, checking horizontal and vertical, and driven into the ground 2 meters.
• Then vertical rods of the calculated diameter are driven in. We determined the installation pitch: 300 mm, in the corners and at the junctions of the walls it is half as much - 150 mm.
• The longitudinal threads of the lower reinforcement belt are tied to the posts.
• At the intersection of the racks and longitudinal reinforcements, horizontal jumpers are tied.
• The upper reinforcement belt is tied, which is located 5-7 cm below the upper surface of the concrete.
• Horizontal jumpers are tied.

It is most convenient and quick to make a reinforcing belt using pre-formed contours. The rod is bent to form a rectangle with the specified parameters. The whole problem is that they need to be made identical, with minimal deviations. And a large number of them are required. But then the work in the trench moves faster.

As you can see, reinforcing a strip foundation is a lengthy and not the easiest process. But you can cope even alone, without helpers. It will take a lot of time, though. It’s easier to work with two or three people: both carry the rods and set them out.

Concrete can withstand bending forces well, but cannot cope with bending on its own. To provide bearing capacity Reinforce the foundation with your own hands. This applies to a greater extent to strip and slab structures. Metal is placed in piles and pillars more for structural reasons than for real necessity.

Reinforcement rules

Reinforcement of strip foundations and any other is carried out taking into account the following rules:

• for working reinforcement, rods of class not lower than A400 are used;
• It is not recommended to use welding to connect the rods, as it weakens the cross-section;
• It is mandatory to tie a metal frame from reinforcement at the corners; welding is not allowed here;
• Even for clamps, smooth reinforcement is not recommended;
• it is necessary to strictly observe a protective layer of concrete equal to 4 cm, this will protect the metal from corrosion (rust);
• when making frames, the rods are connected in the longitudinal direction with an overlap, which is taken to be equal to at least 20 rod diameters and at least 25 cm;
• if metal is placed frequently, it is worth controlling the size of the aggregate in the concrete: it should not get stuck between the rods.

Example of placement of a reinforcing frame
in a strip foundation

A properly prepared reinforcement frame is half the success. It is he who will save the foundation in case of uneven deformations that create bending loads. It is worth considering the issue in more detail using the example of a do-it-yourself strip foundation.

What reinforcement is needed for the structure?

Reinforcement of a strip foundation requires the presence of three groups of rods:

• workers who lay along the belt;
• transverse horizontal;
• transverse vertical.

Transverse reinforcement under a strip foundation is also called clamps. Its main purpose is to connect the working rods into a single whole. Reinforcement of the strip foundation is carried out in strict accordance with regulatory documents. What reinforcement is needed for the foundation? To give an accurate answer, complex calculations are performed.

In order not to hire professionals, you can get by with a simplified option. The technology for reinforcing a strip foundation for a small house allows you to assign sections constructively. This is due to the fact that the tape takes up relatively small loads and works primarily in compression.

To make a reinforcing frame, constructive, that is, minimum permissible, section dimensions are used:

• For working reinforcement - 0.1% of the cross-sectional area of ​​the foundation for the house. Moreover, if the side of the tape is 3 meters or less, the minimum acceptable value is taken to be 10 mm. If the side of the building is more than 3 m long, then the diameter of the working reinforcement cannot be less than 12 mm. It is not permitted to use rods with a cross-section larger than 40 mm.
• Horizontal clamps cannot be less than one quarter of the working diameter. For design reasons, a size of 6 mm is prescribed.
• The diameter of the vertical reinforcement depends on the height of the tape for the foundation of the house. For shallow-depth ones, the dimensions of which are 80 cm or less, rods from 6 mm are suitable.

The rules for reinforcing a deep-type strip foundation provide for the use of rods of 8 mm or more.

Scheme of typical sections of reinforcement bars

If a brick building is being built, it is worth laying reinforcement with a small margin. This option will give confidence in the reliability of the design.

Knitting reinforcement

The strip foundation reinforcement scheme involves connecting the rods using the bonding method. A bonded frame has greater strength compared to a welded one. This is because the likelihood of burning through the metal increases. But this rule does not apply to factory-made elements. Outside the construction site, it is possible to connect parts without significant loss of strength.

Places for tying reinforcement

To increase the speed of work, it is allowed to reinforce the foundation in straight sections by welding. But corners can only be reinforced using binding wire. These sections of the structure are the most critical, so there is no need to rush.

Before knitting reinforcement for a strip foundation, you need to prepare materials and tools. There are two ways in which metal bonding is performed:

• special hook;
• knitting machine (gun).

The first option is available, but is only suitable for small volumes. In this case, laying reinforcement in a strip foundation will take a lot of time. For connection, annealed wire is used, the diameter of which is 0.8-1.4 mm. The use of other materials is not permitted.

Scheme of tying reinforcement for a strip foundation

To build your home, you need to be patient and attentive. You should not save time and money, as this can cause trouble during operation. There should be no problems connecting the rods along the length. In this case, the process is quite simple; it is only important to maintain the minimum amount of overlap.

But how to properly knit reinforcement for a strip foundation in the corners? There are two types of corner joints: between two perpendicular structures and at the junction of one wall to another.

Both options have several technologies for performing work. For corner walls use the following:

1. Hard paw. To perform the work, a “foot” is made at the end of each rod at a right angle. In this case, the rod resembles a poker. The length of the foot should be at least 35 diameters, it is better to assign more. The bent part of the rod is attached to the corresponding perpendicular section. Thus, it turns out that the external frame rods of one wall are connected to the external ones of the other wall, and the internal ones are welded to the external ones.
2. Using L-shaped clamps. The principle of operation is similar to the previous option. But in this case, they do not make a foot, but take an L-shaped element, the side of which has a length of at least 50 diameters of the working reinforcement. One side is tied to the frame of one wall, and the other to the perpendicular frame. In this case, the internal rods must be connected to the external ones. The pitch of the clamps should be three quarters of the height of the basement wall.
3. Using U-shaped clamps. For the corner you need two elements, the length of the sides will be 50 diameters of the reinforcement. Each of the clamps is welded to two parallel rods and to one perpendicular rod.

How to properly reinforce a strip foundation at obtuse angles. To do this, the outer rod is bent to the required degree value and an additional one is attached to it as reinforcement. The internal elements are tied to the external.

Scheme of correct and incorrect reinforcement of obtuse angles

To lay reinforcement at the junction of one wall and another, use approximately the same methods as in the previous case:

• overlap;
• L-shaped clamps;
• U-shaped clamps.

The amount of overlaps and connections is assumed to be 50 diameters. When performing work, it is worth remembering the most common mistakes:

• binding at right angles;
• lack of connection between external and internal elements;
• The longitudinal rods are connected by a viscous crosshair.

You should not repeat these mistakes when building your own home.

Using a crochet hook

Before reinforcing the strip foundation, it is worth learning how to use the working tool. A special gun is rarely used for private house construction; such equipment requires additional costs. Investing in tools is only beneficial for fulfilling orders, and not when building one house.

For this reason, the most common tool for knitting in private housing construction has become a hook. It will be easier to use if you prepare special templates in advance. This part works like a workbench and makes the work much easier. Things will go faster. To make a template, wooden blocks are required, the width of which is about 30-50 cm, and the length cannot be more than 3 m, since such a workbench is inconvenient to use.

The most common way of knitting is crochet

In the wooden fixture you need to drill grooves and holes that will follow the outlines of the rods in the frame. Pieces of knitting wire 20 cm long are laid out in advance in such holes, and then the reinforcement rods are fixed.

In order to understand the knitting technology, you can consider examples. During construction, two options will be required: for crosses (when the elements are located perpendicular to each other) and for overlap connections. In a strip foundation, the second technology is often needed; when constructing a slab structure, the first will be the most relevant.

To connect the laid frame into a single whole when joining with an overlap, the hook should be used in this order:

1. connections are made in several places along the length of the joint, the location of the wire is designated so that it is in the recessed part of the reinforcement profile;
2. the wire is folded in half and placed under the junction;
3. use a hook to hook the loop;
4. the free end is brought to the instrument and placed on it with a slight bend;
5. begin to rotate the hook, twisting the wire;
6. carefully remove the instrument.

For one overlap connection, the procedure is repeated 3-5 times. Connecting the elements at one time, as is done with cross-connection, is not enough. Tying reinforcement under a strip foundation in this case will be unreliable, since fixation at one point does not prevent the elements from shifting.

Proper connection of the frame will ensure the reliability, strength and durability of the supporting part of the building.

Foundation reinforcement is a process necessary to strengthen the structure and increase the service life of the building. In other words, this is an assembly of a “skeleton” that plays the role of a protective component that restrains soil pressure on the walls of the base. But in order for this function to be implemented to the maximum extent, it is necessary not only to correctly calculate the reinforcement for a strip foundation, but also to know how to organize the progress of construction work.

The basis of a strip foundation is a concrete solution consisting of cement, sand and water. Unfortunately, the physical characteristics of the building material do not guarantee the absence of deformation of the base of the building. To increase the ability to withstand foundation shifts, temperature changes and other negative factors, the presence of metal in the structure is necessary.
This material is plastic, but provides reliable fixation, so reinforcement is an important stage in the complex of works.

Reinforcement for strip foundation - steel bar with stiffeners

Foundation reinforcement is required in areas where tension zones may occur. It is noted that the greatest tension appears on the surface of the base, which creates the prerequisites for reinforcement close to the upper level. On the other hand, in order to avoid corrosion of the frame, it must be protected from external influences by a layer of concrete.

Important! The optimal distance of reinforcement for the foundation is 5 cm from the surface.

Since the progression of deformation cannot be predicted, stretch zones can appear both in the lower part (when the middle bends down) and in the upper part (when the frame bends upward). Based on this, reinforcement should pass from below and above with reinforcement with a diameter of 10-12 mm, and this reinforcement for a strip foundation should have a ribbed surface.

This ensures perfect contact with the concrete.

Strip foundation stretch zones

The remaining parts of the skeleton (horizontal and vertical transverse rods) may have a smooth surface and a smaller diameter.
When reinforcing a monolithic strip foundation, the width of which usually does not exceed 40 cm, it is allowed to use 4 reinforcement rods (10-16 m), connected into a frame with a diameter of 8 mm.

Important! The distance between the horizontal rods (with a width of 40 cm) is 30 cm.

The strip foundation, although long, has a small width, so longitudinal tensions will appear in it, while there will be no transverse ones at all. It follows from this that transverse vertical and horizontal rods, which will be smooth and thin, are needed only to create a frame, and not to bear loads.

Particular attention must be paid to corner reinforcement

Particular attention must be paid to the reinforcement of corners: there are often cases when deformation occurs not in the middle, but in the corner parts. The corners should be reinforced so that one end of the bent reinforcement element goes into one wall, and the other into the other.
Experts advise connecting rods using wire. After all, not every type of reinforcement is made from steel that can be welded. But even if welding is permissible, problems often arise that can be avoided by using wire, for example, overheating of the steel, leading to a change in properties, thinning of the rod at the welding site, insufficient strength of the weld, etc.

Reinforcement structure construction diagram

Reinforcement begins with the installation of formwork, the inner surface of which is lined with parchment, making it easier to remove the structure in the future. The frame is created according to the following scheme:
1. Reinforcing bars with a length equal to the depth of the foundation are driven into the trench soil. A distance from the formwork of 50 mm and a pitch of 400-600 mm should be maintained.
2. Stands (80-100 mm) are installed at the bottom, on which 2-3 threads of the bottom row of reinforcement need to be laid. Bricks placed on edge will work well as stands.

3. The upper and lower rows of reinforcement are secured together with the transverse jumpers to the vertical pins.
4. At intersections, fastening is carried out using wire tying or welding.

The video will introduce you to in a convenient way tying reinforcement using a template:

Important! The distance to the outer surfaces of the future foundation should be strictly observed. It is better to do this with the help of bricks. This is one of the most important conditions, because metal constructions should not be based directly on the bottom. They must be raised above ground level by at least 8 cm.

After installing the reinforcement, all that remains is to make ventilation holes and pour concrete mortar.

You need to know this!
Ventilation holes not only help to increase the depreciation characteristics of the foundation, but also prevent the occurrence of putrefactive processes.

Calculation of material consumption

To calculate a strip foundation, you need to know some parameters in advance. Let's look at an example. Suppose our foundation has a rectangular shape and the following dimensions: width - 3.5 meters, length - 10 meters, casting height - 0.2 meters, belt width - 0.18.
First of all, you need to calculate the total volume of the casting, for which you need to find out the dimensions of the base as if it had the shape of a parallelepiped. To do this, we will perform several simple manipulations: find out the perimeter of the base, and then multiply the perimeter by the width and height of the casting.
P = AB + BC + CD + AD = 3.5 + 10 = 3.5 + 10 = 27
V = 27 x 0.2 x 0.18 = 0.972

But that's the calculation monolithic foundation doesn't end. We learned that the base itself, or rather the casting, occupies a volume approximately equal to 0.97 m3. Now you need to find out the volume of the internal part of the foundation, i.e. what is inside our feed.

We get the volume of the “filling”: multiply the width and length of the base by the height of the casting and find out the total volume:
10 x 3.5 x 0.2 = 7 (cubic meters)
Subtract the volume of the casting:
7 – 0.97 = 6.03 m3

Result: casting volume - 0.97 m3, internal filler volume - 6.03 m3.

Now you need to calculate the amount of reinforcement. Let's say the diameter will be 12 mm, the casting will have 2 horizontal threads, i.e. 2 rods, and vertically, for example, the rods will be located every half a meter. The perimeter is known - 27 meters. This means we multiply 27 by 2 (horizontal rods) and get 54 meters.

Vertical rods: 54/2 + 2 = 110 rods (108 0.5 m intervals and two at the edges). We add one more rod per corner and we get 114 rods.
Let's say the height of the rod is 70 cm. It turns out: 114 x 0.7 = 79.8 meters.

The final touch is the formwork. Suppose we build it from boards 2.5 cm thick, 6 meters long and 20 cm wide.
We calculate the area of ​​the side surfaces: multiply the perimeter by the height of the casting, and then by 2 (with a margin, not taking into account the decrease in the internal perimeter versus the external): (27 x 0.2) x 2 = 10.8 m2
Board area: 6 x 0.2 = 1.2 m2; 10.8/1.2 = 9
We need 9 boards 6 meters long. Don't forget to add connection boards (optional).

Result: 1 m3 of concrete will be required; 6.5 m3 of aggregate; 134 meters of reinforcement and 27 linear meters of boards (20 cm wide), screws and bars. The values ​​given have been rounded.

The results of painstaking calculation work

Now you know not only how to properly reinforce a strip foundation, but also how to calculate the necessary components. This means that the foundation you build will be reliable and strong, allowing the construction of monolithic structures of any configuration.