Do-it-yourself rubble foundation. Foundation made of rubble (rubble stone)

First of all, when building a house, you need to decide on the foundation. Solve the questions of what type and what material it will be made of, what type of insulation and waterproofing to use.

If we talk about the material, the choice will be represented by concrete, rubble and rubble concrete options; asbestos-cement pipes are also used for the construction of the foundation. Most often, rubble is used to build a private house.

What is rubble and rubble foundation

Rubble or rubble stone are stones obtained as a result of the development of rocks such as limestone, sandstone, and dolomite. It is either stones of various shapes with irregular angles and irregular shapes, or stones with smooth edges - slabby or bedded.

A rubble foundation, often of the strip type, is a masonry in which auxiliary materials (liquid mortar on clay, lime or cement) require a relatively small amount for its execution. Priority can be given to bedded rubble and stone of the correct shape. Firstly, they are obviously more convenient for laying - even edges and corners are much easier to lay closer to each other, and secondly, the strength of masonry made from bedded and regular stone is 1.5 and 3.5 times higher than from crushed stone, respectively.

What you need to know when choosing a foundation

Disadvantages of a rubble foundation:

• the construction process itself is very long, labor-intensive and expensive;
• it is difficult to ensure construction “with your own hands”;
• long preparation for construction.

The rubble foundation has the following advantages:

• does not require protection from moisture and decorative treatment;
• strength and long service life;
• resistant to water and frost;
• quarry is a material of natural origin.

From the above, we can conclude that a rubble foundation is suitable for a fairly large private house, which requires increased strength and is also designed for a very long service life. But strip foundations made of rubble can also be used for a variety of small buildings, from a cottage to a bathhouse.

Do-it-yourself foundation

A strip foundation made of rubble is perfect for a country house. It is also possible to build a columnar one, but it is much more difficult than the first one.

The first step is to decide on the volume of material. The size of the foundation in height is calculated based on the fact that it must be buried 20 cm below the freezing depth and at least 30 cm above the ground level. The width of the base should be 20-30 cm greater than the width of the wall. Having calculated the volume of material, it is better to purchase it with a small reserve. You will need sand for a pillow under the foundation; you can calculate the volume, knowing that the thickness of the pillow will be about 20 cm. Next, you need to select and prepare the material, if the latter requires it in size or shape. The cement for the liquid mortar must be of a grade not lower than M100. The rubble stone for the foundation must not only be clean and free of cracks, but also not exceed 30 kg. The larger one is chopped to the desired size. This process is called plinting, sometimes after it pinning is done - changing the shape of the stones closer to a parallelepiped. Immediately before laying, the stones must be cleaned of dirt and wet.

To lay a rubble strip foundation, a trench is dug; its depth is determined based on the fact that the foundation must be at least 20 cm below the freezing depth. A layer of sand about 15-20 cm thick is poured onto the bottom of the trench and thoroughly compacted. It should be noted that in heaving soils, gravel is also poured first, and then sand. Afterwards the formwork is installed. Next, roofing felt is laid, this is done with an overlap. When installing a strip foundation, masonry is used “under the bay” in opposition to the formwork or trench walls, if the formwork was not installed. The first layer of stones is made of the largest and smoothest stones. This row is laid along the base, compacted, filled with crushed stone and filled with liquid cement mortar. The next row is laid across the trench, the next along, and so on, alternating the direction of laying.

Having examined the process of building this foundation, you can make sure that it is really lengthy and quite expensive, if you involve hired workers, if you build it yourself, the price of construction will be lower, although this work will take a lot of time and effort. If there are any, the result will be durable, strong, resistant to water and frost, and beautiful.

The foundation made of rubble is reliable and aesthetic, its service life is at least 150 years, and the upper limit is not limited. After all, buildings made using the same technology several centuries ago have survived to this day. When building with your own hands, the most important thing is to choose quality stones, sort them correctly and follow the instructions.

Rubble - stones with uneven edges of different sizes and shapes, obtained by natural destruction of rocks (sandstone, dolomite, shell rock) or blasting. The average size of the fragments is 30-50 cm in diameter, weight – from 25 to 45 kg.

Types by shape:

• torn - all edges of the fragment are uneven and sharp;
• bedded - one of the sides of the cobblestone is smoother and more even;
• flagstone - flat, of arbitrary shape with even opposite sides.

This classification is conditional, since the stone is simply sorted based on the shape created by nature or rough mechanical action; no special processing is performed. Especially large cobblestones are sometimes split into pieces.

These stones are used to make foundations for any buildings, strengthening the almost chaotic masonry with cement mortar. In such a structure there is about 90% rubble. Cobblestones are placed in rows in a trench and secured with concrete. It is more convenient to use bedded and flagstone types. The high base is reinforced with a reinforcing belt. The rubble concrete foundation is suitable for any buildings several floors high, the construction of a basement, outbuildings, baths. It can be used to make a strip and column structure.

One of the most important criteria for choosing this material is availability. In regions with mountainous terrain, it is easiest to buy stone, but delivery to remote locations can be very expensive. It is also necessary to select a cobblestone with a high level of strength - when hit with a hammer, it should not crumble, but only make a ringing sound. Cracking and delamination are unacceptable.

Pros and cons of buta

Not a single column or strip foundation will be reliable and of high quality if, when laying it, the advantages and disadvantages of the materials used are not taken into account.

• Aesthetic appearance. The part that rises above the ground looks like stonework, giving the building a presentable appearance. Does not require additional finishing.
• Environmental Safety.
• Withstands temperature changes and exposure to moisture.
• If the technology is followed, seasonal soil movements are not dangerous.
• Durability amounts to hundreds of years.
• The large load-bearing capacity allows the construction of large structures in area and number of floors from heavy products.
• Not susceptible to fungus, mold and insect damage.

The construction of a rubble concrete foundation is far from a simple process, requiring time and physical effort. This is due to the characteristics of the material and technology:

• The stones have different shapes and sizes; to place them as densely as possible, sorting and careful selection of elements will be required.
• The rubble base must be buried 20 cm below the soil freezing level, so you need to dig a deep trench and gradually lay rows of cobblestones.
• Construction in regions remote from the location of the stone is much more expensive due to the delivery of material.
• All work has to be done with your own hands, since it is impossible to use special equipment.
• Concreting is carried out in stages, so several portions of the cement mixture have to be mixed.

If it is not possible to carry out the work on your own, you will have to hire a team of installers. Masonry by professionals is much more expensive than the construction of other types of foundations.

Step-by-step instructions for laying a rubble foundation

You should make a plan for the location of the tape or pillars, sort the stones by fraction and shape. The smoothest and largest ones should be left at the corners. Study the structure and type of soil, establish the location of groundwater passage and the level of freezing - this is necessary to determine the optimal depth. Most often, 1.5-1.8 m is enough; in areas with a harsh climate and moving soil, they are buried 2 m. It is not recommended to use trench walls as formwork, as they will crumble, deform and take a lot of moisture from the raw concrete. Therefore, the width of the ditch with a tape thickness of 0.5-0.6 m should be at least 2.5 m. This is enough to install formwork on both sides.

The technology provides two methods:

1. Rubble. Laying stone in rows on mortar is similar to brick. With this method, most of the volume is bottled. To implement it, you need to select the most even flat fragments of different sizes and try to place them at the same level.
2. Rubble concrete foundation. Concreting with rubble, it occupies less volume and serves as reinforcement, and is located less orderly. Cobblestones are selected in the middle fraction up to 30 cm.

A solution should be prepared from a grade of cement not lower than M400. To improve plasticity, it is recommended to add liquid soap or dish detergent. The ratio of the main components is classic - 1 part cement to 3 parts sand. When constructing a rubble concrete foundation, fine crushed stone can be introduced. The consistency should be such that the mixture penetrates well into all voids, but does not spread much.

You will need a set of tools: a sledgehammer, a hammer, a building level, a shovel, twine, a trowel. To fill the voids, it is advisable to prepare small crushed stone or pebbles.

Preparatory work

Preparing the site for a strip foundation or rubble pillars involves clearing the site of debris, uprooting stumps, bushes and trees. If the relief is uneven, it is corrected by removing the top layer or raising the masonry to different heights above ground level.

Next, lines are marked and the depth of the trench is determined. For large volumes of excavation work, it is better to carry out using an excavator. Sand is poured into a 15 cm layer at the bottom of the ditch and compacted - it will serve as a pillow. The specifics of further stages depend on the type of base.

Installation of formwork

The formwork is made from removable and non-removable bars and boards or panels. Since wood absorbs moisture, waterproofing from a thick film or roofing felt will be required - it is attached to the walls of the frame and placed on the bottom.

Install gradually for ease of use. After installing one layer, some of the boards are moved higher. For a concrete base, the frame is installed at once to its full height and is not removed upon completion of work.

Method 1: laying rubble.

Careful sorting by thickness will be required. The general principles are to do the dressing as in the case of bricks, to place the largest and most even pieces in the corners, it is allowed to use large cobblestones in some places that will block two rows at once. Layers of stone are placed alternately with the short and long sides.

Instructions for strip foundation:

• Pour concrete 3-5 cm thick into the bottom of the formwork.
• Place large cobblestones in two corners of the trench and install a beacon made of twine - this will serve as a level for the first row.
• Lay the flattest elements in two layers, fill the resulting voids with fine gravel.
• Pour in the next portion.
• Each subsequent row of rubble-tape base is laid before the cement sets; the position of the stones can be adjusted during the process.

When the work is completed and the foundation has dried, the formwork is removed, the ditch is filled with sand or soil, the upper part is waterproofed, and a blind area is made.

Method 2: concreting with rubble.

The solution takes up more space, and the stones are sorted only by size. It should be poured one at a time to avoid delamination.

Instructions:

• At the bottom of the trench, make a cushion of sand and crushed stone and compact it.
• Pour 20-30 cm of mixture.
• Lay the first layer of rubble and drown it ⅔ into the DSP. The stones should not touch the walls of the formwork so that they are completely immersed in the solution.
• Remove air cavities and bubbles using vibration equipment or a rod.
• The layer rising above the ground, or the last 50 cm, is made using reinforcement and without cobblestones.

The formwork is not removed to ground level; the panels are dismantled only above it. The upper part is laid with waterproofing and a blind area is equipped.

Historically, the rubble foundation is the oldest foundation, still popular for the construction of 1-2 storey buildings. Buildings built in antiquity on rubble foundations still stand today. The service life of a stone foundation is now estimated to be at least 150 years. Such foundations are most resistant to freezing and the effects of groundwater. And natural stone is a beautiful and environmentally friendly material.

There are strip rubble foundations and columnar foundations

To make a decision, let’s look at the rubble foundation and take into account all the pros and cons. Remembering that the foundation is the most important part of the building, let's get started.

The advantages of buta bases include:

• Durability. Natural stone is more durable than concrete, and the service life of a rubble foundation is usually more than 150 years;
• Environmental cleanliness;
• The water resistance of a rubble concrete foundation is higher than that of a reinforced concrete foundation;
• Masonry made of large natural stone has an attractive appearance.

It is important to know about the disadvantages. The disadvantages of a rubble foundation include:

• Relatively high price of buta when purchasing it;
• Laying stone is a longer process than pouring a reinforced concrete base;
• Natural stone laying skills required.

Please note that a large bottle can weigh more than 10 kg. Working with stones weighing more than 30 kg is not recommended

Rubble stone, which one to choose?

Cote is not a specific type of rock. Rubble stone is a torn or rounded natural stone ranging in size from crushed stone to large stones whose weight can exceed 30 kg.

Natural stone in construction is used in different types: light, heavy sedimentary or volcanic.

Rubble strength

Depending on the rock, the strength ranges from 2 MPa to 30 MPa.

Frost resistance

The frost resistance of rubble is assessed by the number of cycles of successive freezing, while the stone should not crumble and lose no more than 5% in weight. This parameter models the number of cold seasons for a buta without destruction.

15 or more cycles are acceptable.

The quality of the cement mixture (in terms of strength and frost resistance) must correspond to the selected stone

Flakiness

A characteristic that determines the shape of grains in a stone. There are 5 groups, depending on the content of lamellar grains from 10% (group 1) to 35-50% (group 5).

Flakiness affects strength (1 group is stronger than others), and somewhat increases the labor intensity of working with such a stone.

Radioactivity

Rocks can be dangerously radioactive.

In construction, 2 groups of rocks according to radioactivity are allowed:

• Up to 370 Bq/kg – allowed for the construction of residential buildings, as well as construction inside populated areas;
• Over 370 Bq/kg is not allowed for the construction of residential buildings, as well as construction inside populated areas (such material can only be used for industrial buildings).

Rubble stone is distinguished by shape

When choosing a rubble for the base, you need to decide not only on the type of rock, but also on the shape.

Depends on the form:

• ease of laying, which affects the work time;
• appearance;
• consumption of cement mixture.

Rounded bottle

A stone that was mined in the surf zone, in places where glaciers exist today or during the Ice Age.

This stone has a rounded, rounded shape. This kind of rubble is not suitable for a foundation.

Bedbed

A butte, the two sides of which are close to parallel, is called bedded. It turns out something like uneven natural brick (if you look at it uncritically). Thickness not less than 70 mm.

Unlike rounded ones, bedded rubble is most convenient for masonry; it also allows for dry masonry (without mortar).

Species from which bedded rubble is produced:

• Sandstones
• Limestones
• Layered rocks

Industrial bottle

Natural stone is extracted using blasting. After sorting into fractions it goes into sale. Has a “ragged” shape

Not in good condition

The stone must be clean, not crumble and not crumble when hit with a hammer.

A ringing sound when struck with a hammer is good!

DIY rubble strip foundation

We suggest learning how to build a rubble foundation for a house with your own hands. You can both seriously save money by carrying out the work yourself and control the work on the construction of a rubble foundation by understanding the process.

Calculation

To calculate, you need to collect:

• Weight of the superstructure (walls, windows, floor, ceiling, roof, utilities);
• Maximum payload (finishing, furniture, residents, water supply and heating);

It is also necessary to determine the soil parameters on the site.

• Soil type;
• Freezing depth;
• Height of groundwater.

Let's say:

• weight per foundation 50,000 kg;
• building size in plan 4 x 3 m;
• without basement;
• located near Tver;
• soil – loam (soil resistance 1.5 kgf/cm2;

• groundwater below 3m;
• Freezing depth 1.4 m.

Calculation of the foundation body

Foundation support area:

50,000 / 1.5 *1.3 = 43,333 cm2 or 4.33 m2 (1.3 – safety factor)

The minimum width of a rubble strip foundation is 40 cm. If necessary, increase the foundation support area

The perimeter of the building is 14 m.

With a foundation thickness of 40 cm, the foundation support area will be:

14 * 0.4 = 5.6 m2

The depth of the foundation should be 20 cm greater than the freezing level.

Freezing depth of various soils by region, m

The height of the foundation base (height above ground level) is recommended to be 40 cm or 20 cm above the snow cover (whichever is greater). In our calculation we will take 40 cm.

Foundation volume:

5.6 * (1.4 + 0.2 + 0.4) = 11.2 m3

For 1 m3 of foundation you need 1 m3 of rubble and 0.35 - 0.5 m3 of cement-sand mortar for masonry.

11.2 m3 of rubble

3.9 – 5.6 m3 of solution

Calculation of material for a cushion on a rubble foundation

Please note that the width of the ditch under the foundation strip should be 60 cm greater on the side where the mason will move, and 30 cm on the opposite side (provided that the width of the foundation allows working on one side).

A sand cushion is, first of all, needed to level the bottom of the pit and to distribute the load on the ground evenly.

The thickness of the sand cushion is 20 cm (minimum).

To reduce labor costs, we will lay the foundation in a trench with the following width:

0.4 + 0.3 + 0.6 = 1.3 m

The volume of the sand cushion will be:

1.3 * 0.2 * 2 * (4 + 3) = 3.64 m3

Taking into account the reserve (including for leveling) 30%:

3.64 * 1.3 = 4.7 m3

Preparatory work

• Marking the foundation;
• Digging a pit;
• Leveling the bottom of the pit;
• Laying a sand cushion (preparation);
• Wash and sort natural stone:

First of all, you need to wash the stone from dirt and check whether it is good (the stone should not fall apart when hit by a hammer, it should not peel off).

If there are stones larger than 30 kg (or the weight that you have determined is comfortable for masonry), you need to break them.

The first one will contain small stones. We will use them to fill the voids in the masonry between large stones.

The second group will include stones convenient for laying out corners and junctions. These stones are distinguished by their larger size and relatively regular shape.

The third group is all other stones.

Rubble masonry

Now it's time to move on to laying the stone. Please note that with the exception of the first layer, the stones are laid on mortar.

This is important: the stones should not touch. Leave a gap of 3–5 cm between the stones in the row.

The stone must be wet before laying.

a stone laid along the foundation is called a spoon, and across it is called a poke

There are three technologies for rubble masonry: “under the shovel”, “under the gulf”, “under the bracket”.

Under the shoulder blade

Rubble stone is uneven, and rows of it cannot be made even. But you need to try so that the next row, as it were, compensates for the unevenness of the previous one and all rows are relatively parallel.

• The first to be laid is the bonded row on a cushion without mortar, the stones are compacted, the voids between the large stones are filled with small stones or crushed stone;
• A layer of concrete is laid (cement-sand mixture in a ratio of 1:3, cement grades M400 or M500), the concrete must completely cover the stones;
• The spoon layer is laid;
• Continue alternating the bond and tray layers on the concrete mortar until the design height of the foundation is reached;
• To level the horizontal surface of the foundation, use thicker concrete.

Observe ligation of stitches!

Under the bay

This type of masonry is made without selecting stones or bandaging voids.

• The rubble is laid in rows;
• Filled with mortar (cement-sand mixture 1:3 from cement M400, M 500) and compacted (it is recommended to use vibrating mortar compactors);
• Repeat until the target height is reached.

This method requires formwork. The size of the buta is not so important. A rubble foundation made using the “bay” technology has reduced strength.

Under the bracket

The method is almost no different from “under the blade”, except for leveling the stone in height using a measuring bracket (which gave the name to the masonry method). This reduces the complexity of masonry, but increases the complexity of preparatory work.

After gaining 50% strength, you can move on to subsequent work.

At an average daily temperature of 20°, concrete gains 50% strength in three days

The initial stage of construction of almost any engineering structure is the construction of the foundation. And natural stone, also known as rubble, is ideally suited for the role of a reliable and environmentally friendly filler for a sand-cement mixture. Due to the irregular geometry of the material, many believe that working with stone, the creator of which was Mother Nature, requires a certain skill and skill. In reality, this is not entirely true, and you can competently arrange a rubble stone foundation with your own hands even in the complete absence of special training: a simple desire and a moral and psychological attitude towards physical labor will be quite enough.

The process of starting the personal “sculpting” of the foundation should be preceded by the purchase of fine crushed stone (it will be needed for filling voids), the purchase of sand and cement (to form a “cushion” for the future concrete foundation and the possibility of preparing a working mixture), as well as the delivery of rubble stone to the site ( the latter must meet the stated criteria of strength, frost resistance and water resistance). It is also worth taking care of the availability of waterproofing material (roofing felt).

Pouring a good foundation with rubble stone, and then building a house on top of it, without having the appropriate tools at hand, is an unsolvable task. So, inventory. Among other things, you will need:

1. several shovels and bayonet shovels;
2. a durable and sufficiently spacious container for mixing the solution;
3. trowels with different working surface areas;
4. rule-level and its water analogue;
5. construction tape and plumb line;
6. a manual or mechanical rammer, a heavy sledgehammer, a stone hammer (pick), and a chisel.

Armed with the tools and having prepared all the consumables in the required volume, you can finally begin to find the answer to the question of how to make a rubble stone foundation without the involvement of specialists.

Technological features of constructing a rubble stone foundation: installation of the bottom layer

The foundation, the main filler of which is natural stone (rubble), is laid at a certain depth (depending on the reliability of the soil foundation). Moreover, the installation depth must necessarily exceed the maximum level of soil freezing. The actual digging of trenches is preceded by the breakdown of the area according to the development plan. Digging of the soil is carried out on the basis that the width of the excavation will make it possible to build a foundation “with a margin”, that is, the distance from the edge of the load-bearing walls of the future structure to the border of the concrete foundation will be at least 10-15 cm. Often during excavation work “embarrassments” arise "caused by uncontrolled shedding of soil into the trenches. A solution to the problem can be primitive formwork, made from improvised boards or sheets of metal, which is removed immediately after the pouring process is completed.

In the dug trenches, a so-called “sand cushion” is created. This is done in several stages, with each layer of sand being thoroughly compacted and moistened. At the final stage of “trench work”, the waterproofing layer is installed on an already prepared “cushion” at the bottom of the excavation: sheets of roofing felt, or its equivalent, are evenly laid “overlapping” (thereby minimizing unexpected moisture loss during the hardening of the concrete-stone belt) . It is worth noting that, without having experience in the installation of such structures, it is preferable to build a strip foundation from rubble stone rather than try to master the technique of pillar laying “at once.” The second option involves the need to look for answers to complex questions, such as balancing a monolithic base, calculating optimal “threshold” points, and the like.

Natural cobblestones with the most even (flat) horizontal surfaces will serve as the “support” on which both the foundation itself and the structure being constructed (house) will subsequently “sit”. Stones with this geometry should be pressed into the sandy base at the bottom of the trench, and at the same time controlled so that they do not swing and are directed along the excavation, and not across. It is quite likely that the purchased batch of rubble will not contain such “suitable cobblestones” for laying in the first row of the base.

There is no need to panic: you will have to arm yourself with a chisel and a hammer-pick and independently “correct the defects” of the natural material.

As the rubble is pressed into the sand “pillow”, small depressions and openings will certainly begin to form. To get rid of them, you will have to resort to tamping again. However, this time compaction involves the additional use of finer filler (crushed stone or pebbles). It looks like this: the voids between the rubble are filled with fine-grained crushed stone, after which these zones are methodically processed with a sledgehammer until the surface is completely leveled. And only after this is the first layer of the base filled with cement-sand mortar (at a ratio of 1:3).

It is important to understand that when making a rubble stone foundation with your own hands, you take full responsibility for compliance with construction safety standards. So, say, if the height of the same first layer in the base is not maintained, then there will be a high probability of critical deformation of the concrete structure. (It is recommended to lay rubble at the bottom of the trench in such a way that after the initial pouring, the height of the layer fluctuates between 30-40 cm.)

Laying and, accordingly, pouring the second and subsequent rows of rubble foundations is carried out according to the algorithm described above. The only difference is that the seams are periodically bandaged, as in standard brickwork, and the natural stone itself is mounted directly on the uncured mortar.

A separate topic is reinforcement. A high foundation needs additional stabilization using strong wire or reinforcement. As a rule, the last 3-4 layers of the structure are reinforced. Regular tamping and shaking of the moving mass of each new level will guarantee that the construction of a rubble stone foundation will take place without technological deviations.

Practical recommendations for arranging a rubble foundation: optimization of the work process

Professional builders have long developed algorithms for optimizing certain processes, and no one can prevent amateur beginners from arming themselves with this knowledge, who, say, set out to learn from their own experience how to lay a rubble stone foundation. So, here are some practical tips that can significantly reduce physical stress when installing a concrete base yourself:

• the presence of gentle slopes in the trenches dug for pouring the rubble foundation makes it possible to equip a comfortable working platform between the bottom of the excavation and its walls (accordingly, the supply of mortar and stone is accelerated);
• the problem of steep slopes is solved by installing wooden scaffolding;

• It is advisable to place containers for cement-sand mortar on the sides of narrow and shallow trenches, and pile rubble in the spaces between them;
• advance “reservation” of space for openings for laying communications and ventilation reduces the construction time of the foundation by several days;
• the required volume of all consumables must be calculated before pouring begins, so as not to disrupt the installation technology.

The relevance and demand for foundations based on rubble stone is largely due to their high load-bearing capacity and durability, but its impeccable aesthetic appearance also plays an important role in the popularization of the natural material. Designs made using natural cobblestones often eliminate the need for additional finishing work. In addition, the rock is very “friendly” towards other facing products, which certainly plays into the hands of supporters of economical construction. And most importantly: in order to make a foundation from rubble stone yourself, you don’t need to be a world-famous architect or have seven spans in your forehead! Armed with patience and following simple rules and recommendations, almost any person is able to master a technology whose history dates back centuries...

Rubble foundations have been known to mankind for a very long time. Today, such a foundation for construction is affordable and beautiful. Its service life reaches 150 years; even fortresses were once built from this stone.

In addition, such a foundation is the most resistant to groundwater and soil freezing among other foundations. Developers also choose it because of its environmental friendliness. It’s quite simple to build such a structure yourself, and you don’t have to use any special construction equipment.

Description

If we consider a standard rubble foundation, we can note that its strip variety usually has a height of about 1.6 m. A reinforced belt is laid on top. If the base is prepared with sand and drainage, then the height can be reduced, as in the case of a reinforced belt.

The laying is carried out below the soil freezing line, using concrete grade M100 or higher. The base should be about 30 cm above the ground level, then comes the base. When dismantling the buildings of the last century, it became clear that the described type of foundation was then laid to a depth of up to 2 m, no reinforcement was used, and fastening was carried out with a simple mortar.

There was no waterproofing or brick placed between the wall and the foundation. Despite this, the buildings continued to stand. This suggests that rubble stone in such a foundation replaces a metal frame. The main role in this case is played by rubble, the content of which can reach 90% of the total volume. There are no requirements for the size and shape of the stones.

Peculiarities

The material can be chipped or tiled, with the main condition being the strength of the material. It is better to use bedded or tiled rock during the work. It has smooth edges, which allows you to get an advantage when laying, because smooth stones lay easier than those that have irregular edges.

The masonry technology of this material is often compared with the technique that describes the construction of brick walls. The principle here remains the same. The elements are stacked on top of each other and bonded with mortar. The only difference is the building blocks and the composition of the solution. Brick is laid on a cement-sand mortar with a large volume of sand, while rubble stone is mounted on more durable concrete.

Positive reviews

Before building a rubble foundation, you should familiarize yourself with its advantages and disadvantages. You can find out about them by reading reviews. Among the advantages, consumers highlight:

• environmental cleanliness;
• durability;
• aesthetic indicators;
• high moisture resistance.

Consumers especially emphasize another useful property: the construction process can be reduced in cost by adding other building materials. For example, the recessed part that will be in the ground can be formed from pure rubble, while the surface in this case is laid out from brick.

Negative reviews

If you plan to lay a rubble foundation yourself, you should read the negative reviews. Thus, home craftsmen note that there is no point in harboring illusions about the speed and ease of erecting such a foundation, because these assumptions do not correspond to reality. So, to construct the described foundation, a deep trench is required. And the bottom is buried 20 cm below the freezing point of the soil. In some regions this figure reaches 2 m, but most often it ranges from 150 to 180 cm.

In addition, digging a trench and taking measurements requires a lot of time. Consumers emphasize that in this case even heavy earth-moving equipment may be required. Developers advise choosing stones very carefully, because after that they will have to be laid out throughout the entire volume of the foundation as evenly as possible. If you plan to build a rubble stone foundation with your own hands, you should familiarize yourself with the disadvantages of the building material. Among them, home craftsmen distinguish:

• high cost of materials;
• the need to carry out complex calculations;
• difficulties associated with the delivery of material to the construction site;
• there is a high probability that specialists will have to be involved in the work.

Construction technology: preparation of tools

Before starting work, you need to stock up on tools and materials, among them the following should be highlighted:

• fine crushed stone;
• sand;
• cement;
• rubble stone;
• bayonet shovels;
• a spacious container for the solution;
• trowels;
• roulette;
• building level;
• plumb line;
• tamper

Crushed stone will be needed to fill the voids that are formed during the laying process. But the sand will be used to prepare the solution and make the pillow. When purchasing cement, you should choose one that has the M400 grade. The volume of rubble stone will be less compared to the volume of the trench. The smaller the stone, the more it will be needed. It also depends on the evenness of the edges.

The construction of rubble foundations involves the use of rubble with high frost and water resistance. The stone must be durable. It is also important to take care of the presence of roofing material or other waterproofing material.

Construction of the first layer

The foundation is laid at a depth below freezing of the soil. Much also depends on the looseness and composition of the soil. A trench is laid out on the ground using rope and pegs. The width must be planned so that it is 15 cm larger than the walls.

If the soil crumbles during the digging process, then it is necessary to construct formwork from boards and other materials. They are usually removed after concrete has been poured and hardened. A sand cushion is placed in the trench. It is done in several stages. Each subsequent layer of sand is compacted and moistened.

At the final stage of excavation work, it is necessary to lay waterproofing on top of the cushion. For this purpose, roofing material or its analogue is used. It is necessary to lay the sheets overlapping so that moisture is not lost from the concrete.

Having chosen the most even and flat cobblestones with a horizontal surface, they are laid on the bottom - this will create a base for the rubble. Smooth stones are pressed into the sand. In order to get rid of recesses and openings, you should use a tamper. The voids are filled with pebbles and small crushed stone. The layer is compacted and then pressed with a sledgehammer. This layer can be filled with concrete mortar, which is prepared in classic proportions: one to three.

Laying the remaining rows and reinforcement

So, you have chosen a rubble stone foundation as the base. The first steps have been taken, then you can begin laying the next rows. The first layer can be poured at a height of 40 cm from the bottom. The laying and filling of the remaining rows follows the same principle. The only difference is in the bandaging of the seams, as in conventional brickwork.

The stones of subsequent rows are placed in uncured mortar. Strengthening the rubble foundation is required if the foundation is planned to be high enough. Additional stabilization is expressed in the laying of reinforcement or wire. The last four layers of the structure should also be formed. It is important to systematically compact the moving mass in the new layer, which will guarantee the strength of the future foundation.

Work methodology

In order to speed up the flow of stones and mortar into a deep trench, gentle slopes should be made in the walls. This will allow you to create a convenient platform between the bottom and the walls. The problem of steep slopes can be solved with the help of wooden scaffolding.

If the trench is quite shallow and narrow, then the container for the solution can be installed on the sides, and stones can be placed between them. Openings for ventilation and communication should be planned and laid immediately. This will shorten the construction period and reduce labor costs.

Before laying, the material is wetted to ensure better adhesion to the concrete. The stones are laid with a gap ranging from 3 to 5 cm. The long side of the rubble is called a spoon, the short side is called a poke. In each row, the poke should alternate with the spoon.

For masonry it is convenient to use a hammer-cam and similar tools. The thickness of the masonry is approximately 70 cm. For plasticity, clay is often added to the solution, but do not be zealous.

Rubble stone under the foundation can be laid using one of two technologies:

• under the shoulder blade;
• under the bay.

In the first case, we are talking about a technology that involves preparing the base, as well as laying a dry bonded row on it. The stone is well compacted, and the voids are filled with small stones. At the next stage, you can begin to fill the space with liquid solution.

The next step will be laying the spoon row. The thickness of the first and second rows should not exceed 30 cm. The stones are selected in such a way that the height of the row is almost the same. To check, you can use beacons with a cord. It is important to ensure that the stones do not touch each other without mortar.

A rubble strip foundation can ultimately turn out to be perfectly smooth; for this, formwork is usually installed. In this case, the walls are subsequently finished with one of the many materials that are available on the market.