Columnar foundation for a house made of timber. Columnar foundation - pros and cons, construction features. Strip foundation for a timber house

Building a foundation for a house on a country plot is a responsible undertaking. And even if you decide to entrust this work to a contractor, you need to know as much as possible about the supporting foundations for the house.

How to choose a foundation design for a wooden house

The supporting foundation for a house is arranged taking into account many different circumstances. After all, the durability of the building and the safety of living depend on its design. If the foundation is not built correctly, the house will be constantly damp, accompanied by mold and a nasty putrid odor.

When laying the foundation, the following factors must be taken into account:

1. Location of the building. After selecting it, it is necessary to carry out exploratory drilling in order to accurately determine the composition and characteristics of the soil at the site where the support base will be installed. wooden house. It is not advisable to install a house near natural reservoirs or ravines, since the soil in such places is unstable. It is also necessary to clarify the possibility of laying communications: water supply, electricity, sewerage.
2. House size. This factor directly affects the amount of load on the foundation, and both the height of the building and its number of storeys matter. The perimeter dimensions are not so important, since as they increase, the supporting surface also increases.
3. Availability basement or ground floor.
4. Surface topography at the installation site. For example, when building on a slope, the use of a strip foundation is associated with large volumes of excavation work.
5. Properties of the soil base. The quality and composition of the soil can be determined by the nature of water flow after rain:
   • clay soils slowly allow water to pass through, and if they come to the surface, a dense crust forms on them;
   • loams quickly allow moisture to pass through, but dry out slowly;
   • sandy soil drains water quickly;
   • Peaty soil takes a long time to dry out, and grass does not grow well on it.

Each soil type has a different bearing capacity. Great importance has the depth of groundwater and the freezing point of the soil.

Types of foundations

In suburban construction, the following types of support foundations are used:

• columnar;
• pile;
• tape;
• slab.

The types of foundations are not limited to the above list, which shows only the most commonly used forms.

Columnar structures

They are made in the following order:

1. Site preparation - you need to remove the turf layer and all plants.
2. Mark the foundation and use pegs to mark places for installing pillars. In this case, the distance between their axes should not exceed two meters. Pillars must be installed at each intersection or junction of the foundation along the perimeter of the marking and under the internal partitions.

   Places for installing poles must be marked with pegs

3. Drill holes for the posts. The depth of the pillar should be greater than the freezing point of the soil where the foundation is installed by 30–50 centimeters.
4. At the bottom of the pit you need to arrange a sand and gravel cushion. First, a layer of sand 10–15 centimeters thick is poured, then gravel of the middle fraction and both layers are compacted tightly. For better compaction, the bedding can be shed with water.
5. Make reinforcement using steel reinforcement with a diameter of 6–8 millimeters. The reinforcement mesh frame is made on the surface and lowered vertically into the pit. Depending on the size of the column, a four-rod or six-rod reinforcement method can be used.

   The reinforcement cage is lowered vertically into the well

6. Install the formwork at the required height. For wooden house the protrusion of the pillars above the ground must be at least 50 centimeters. All upper sections of the formwork must be aligned strictly horizontally and at the same height along a stretched cord. Pillar heads can also be made with brickwork.
7. Once the pillars are ready, you can install a grillage on them - the supporting foundation of the house.

When digging pits, it is advisable to use TISE technology. This means that a widening is created at the bottom of the pit, increasing the area of ​​support of the foundation on the ground.

Pile foundations

For a wooden house without a basement or ground floor, the most suitable option for constructing a support base is a pile structure. The marking procedure and rules for placing piles are the same as for a columnar foundation.

A pile foundation is installed on soft soils and if there is a slope on the site. The reason for constructing such a support base is also the nearby groundwater.

The main structural element is metal screw piles. They are wrapped in soil, aligning the upper ends along a stretched cord. A grillage is mounted on top of the pillars. It can be made from the following materials:

• wooden beam;
• metal profiles - beam or channel;
• cast concrete grillage.

The advantage of pile devices is the complete absence of excavation work and the quick installation of the foundation.

The disadvantages include the impossibility of installing a basement or basement. Difficulties also arise when setting up a garage.

Strip foundations

Such support bases are the most popular in the construction of wooden buildings of any type. For the manufacture of strip foundations, the following technology is used:

1. The foundation is marked using pegs and a cord.

   The marking is made so that the corner of the tape is at the intersection of the stretched cords

2. WITH work site the soil layer and plants are removed.
3. According to the markings, trenches are dug to the designed depth, taking into account the freezing point of the soil. The width of the trenches should be the size of the foundation plus 40–50 centimeters for convenience during work.
4. A drainage layer of sand and crushed stone of the middle fraction is poured onto the bottom, spilled with water and compacted. The gravel-sand cushion will protect the foundation from the effects of ground movements.

   The drainage bedding must be compacted using special equipment or manually

5. The formwork is being installed. The material for its manufacture must be selected taking into account the possibility of its reuse. For example, if you plan to install a roof made of metal tiles or other similar material, it is advisable to use planed boards for formwork. After dismantling, the boards can be used for sheathing. When installing a roof made of bituminous shingles, you can use plywood for formwork, which will be needed for the roof. To protect materials from contact with concrete mortar, before reinforcement, the formwork walls are covered with plastic film.

   The material for formwork must be selected taking into account the possibility of its further use.

6. Reinforcement is made with steel rods with a diameter of 6–8 millimeters. The reinforcement mesh pattern can be four- or six-bar depending on the size of the foundation. The maximum distance between the rods should be no more than 40 centimeters.
7. Concreting is carried out layer by layer in a continuous mode.

The holding time of the foundation until complete crystallization of concrete is 28 days. In the hot season, it must be covered with film and periodically watered. Premature drying of concrete will lead to cracking of the foundation.

At the end of this period, the supporting foundation is ready for further construction.

Slab foundations

Such structures must be installed during construction on the most unreliable soils using the following technology:

1. Mark the site, remove the soil layer and vegetation.
2. Compact the soil in the cleared area using a vibrating plate. In this case, it will settle to a depth of 50 centimeters.

   The bottom of the dug pit must be compacted

3. Cover the compacted surface with a layer of geofabric overlapping the walls.
4. Arrange a drainage layer of sand and gravel, level and compact it.

   A drainage bedding is made in the pit and formwork is installed

5. Lay a layer of insulation from foam polystyrene boards, wrap the geofabric overlap.
6. Perform waterproofing with bitumen mastic. Before applying it, you need to treat the surface with a primer in accordance with the recommendations on the bitumen resin packaging.
7. Install a reinforcing mesh made of steel bars with a diameter of 8 millimeters. The distance between the rods should be no more than 40 centimeters. The thickness of the slab should also be about 40 centimeters.

   The mesh size of the reinforcement mesh should not exceed 40 cm

8. Concrete pouring must be done continuously in one go. It is best to use the services of a concrete pump and a team of concrete workers for this, since you will need specific equipment - concrete vibrators.

Conditioning and maintenance of the foundation should be carried out as indicated above.

Do-it-yourself foundation construction

It should be noted right away that it is impossible to make a high-quality support base alone. Already at the marking stage, you will have to invite an assistant to check the quality of the work performed. But the main difficulties will arise during the installation of formwork, reinforcement and concreting. It is important to pour the foundation in one go, otherwise a seam will form, which can subsequently become a source of crack initiation.

To perform all operations quickly and efficiently, you will need the following equipment:

1. Entrenching tool for digging trenches.
2. Measuring instruments for checking horizontal and vertical surfaces. It is advisable to have a plumb line and a construction laser level.
3. Carpentry tools for the manufacture and installation of formwork: saw, axe, hammer, nail puller.
4. Vibrating plate for soil compaction.
5. Concrete mixer for preparing the solution.
6. Vibrator for compacting concrete mortar.

It should be noted that all equipment can be rented.

Photo gallery: foundation pouring tool

Portable vibrator for concrete compaction Preparing concrete using a concrete mixer is much faster and easier Laser construction level will ensure the accuracy of horizontal alignment Tool for compacting soil foundations

1. When preparing the solution yourself, you need to control the quality of the water if it is taken from natural sources. The water should be free of small insects and vegetation.
2. When concreting, you need to carefully compact the concrete and pierce it with a pin, preventing the formation of air bubbles.
3. Pouring concrete should be done along “beacons” positioned strictly horizontally. To do this, you can use wooden blocks, metal corners of the required size or pipes. All of the listed materials may be useful in further work, so they need to be removed from the concrete a few days after pouring. The remaining cavities in the foundation surface must be sealed with mortar.
4. The distance from the frame beam of the house to the ground must be at least 50 centimeters.
5. Waterproofing must be applied to the surface of the foundation. Under the first beam it is necessary to lay protection from moisture in the form of a double layer of roofing material.

Video: do-it-yourself pile-strip foundation

Laying the first timber on the foundation

The lower crown of a wooden house fails faster than others. Therefore, its design should be as maintainable as possible.

Installation of timber on a concrete plane

To fix it, two methods are used:

1. Stud - embedded in the foundation when pouring, its height should ensure through passage through the beam and placement of a nut with a wide washer on top of it. After tightening, the protruding end is cut off with a grinder.
2. A rod is installed into the monolith of a grillage, slab or tape during concreting. During the installation of the first beam, holes are drilled in it and it is put on protruding dowels.

Installing the first beam on poles or piles

In such cases, fastening is carried out only with dowels or threaded rods. During repairs, dismantling is carried out using jacks, after which the worn timber is cut out and replaced with a new one.

Fastening to screw piles is done with self-tapping screws onto additional plates, which are welded to the pile head. This is especially convenient to do from below, since the gap between the ground and the timber for a wooden house is at least half a meter.

Video: laying the first crown of a timber house

Now you can make qualified decisions on any issues regarding foundation construction and make it yourself. And if it is done by a contractor, he will not be able to deceive you. I wish you success!

Despite the fact that the weight of a house made of timber is significantly less than that of a similar house made of brick, this is not a reason not to carefully calculate the foundation for a house made of timber. It is frivolous to neglect the issues of arranging the foundation of such a building.

Existing options

The foundation for a timber house can be built by any of the currently known types. However, the most popular options are:

• Strip foundations are the most common type for wooden houses lately. This option is the key to an adequate level of stability of the structure’s frame in most soil conditions;

• Columnar is a very economical option. When erected, a reduction is achieved building materials and the scope of the work itself. Accordingly, the price of constructing a foundation of this type is lower than that of others;

• A pile foundation is a reinforced variation of the columnar type. Characteristic Features This option is more powerful types of “pillars” and a much greater depth of their placement in the ground.

Stages of construction of a strip base

Properly calculated dimensions of the foundation for a house made of timber provide a high margin of safety for the future building. And this determines the safety of its further use.

Marking the area for the foundation

At the initial stage of constructing a strip foundation, it will be necessary to mark the construction site based on the size of the foundation.

Note! It is necessary to outline the boundaries of the future structure with particular precision, since there will be no opportunity to correct mistakes after the foundation is built.

• The fishing line needs to be secured to the reinforcement;
• Using a level, you should select a straight line under the foundation zero;
• Installation of cast-offs is carried out at a distance of 1 - 1.5 m from the facade of the building;
• First you need to remove the plant layer of soil and level the site;

Note! The width of the foundation for a house made of timber is calculated based on the design of the building walls, but not less than the width of the wall, which is increased by 10 cm.

• After marking the perimeter, reinforcement should be driven into the ground;
• Next, you need to check the corners of the foundation and tighten the fishing line;
• Then it’s worth marking the internal boundaries and partitions of the foundation, keeping in mind its width. The width of the strip foundation for a timber house usually ranges from 30-40 cm.

Pit preparation

The standard pouring depth for the foundation of a wooden house is 0.4 m, and the thickness of the sand cushion is 10-15 cm.

As a result, you should get a pit with the depth:

• at its lowest point around 0.55 m;
• and at the top - 0.7 m from the surface of the earth.

The bottom level must be leveled according to the horizon level.

If we multiply the total length of the pit by the arithmetic mean value of the depth, we get the cubic capacity of the excavation work. This will also include the value obtained by multiplying the height of the sand cushion by its thickness.

sand cushion

In order to reduce the load on the foundation under a log house during seasonal swelling of the soil, use sand cushion. Its upper part will need to be thoroughly compacted, leveled using a level.

Advice! By multiplying the length of the trench by its width and the thickness of the cushion, you can understand how much sand will be needed. However, it is not worth calculating this parameter back to back, during construction work sand is always useful.

We construct the formwork

Formwork is a removable or permanent structure that gives concrete its shape:

• The end parts of the shields are assembled using self-tapping screws. This technology makes it possible to prevent loose fitting of structural elements and penetration of the solution into the cracks between them;
• After the shields are assembled, they need to be strengthened with spacers;

• It is also important to fix the roofing material on the inner walls of the formwork with your own hands. This is done so that the liquid part of the concrete solution is not absorbed into the boards, and the outer walls of the foundation remain smooth.

Reinforcement

The reinforcement is intended to strengthen the strip foundation. However, only one whose cross-section exceeds 12 mm is suitable. Thanks to its presence, its service life increases significantly.

The instructions state that the reinforcement should be placed at a distance of 3-5 cm from each edge of the foundation:

• Jumpers are fixed to each of the lower rods using knitting wire at a distance of 40 cm;
• Next, vertical rods are attached to the corners of the resulting cells;
• Both the upper and middle rows of horizontal rods are processed in the same way.

Pouring concrete

You need to prepare your own concrete solution:

Advice! The brand of cement is selected based on weather conditions and characteristics of the construction site.

1. To do this, take three parts of sand, three parts of crushed stone and one part of cement;

Wooden buildings cannot compare in durability with brick and stone ones, but due to their affordability they are popular, especially as country houses and country houses. Up to a third of the cost of a building is the cost of constructing the foundation, so the choice of design and materials for its manufacture should be approached carefully. There are several ways to build a foundation for a house made of timber; let’s look at the main ones.

Common types of bases

Unlike massive stone buildings, they do not require deep foundations.

For wooden buildings, it would be more rational to construct a base of a strip or column type, placed at a depth of no more than 70 cm, or a sand “cushion”. Let's take a closer look at each type.

Tape

(monolithic) is a reinforced concrete strip located around the perimeter of the house, buried in the ground. The construction of such a foundation requires a lot of concrete and reinforcement, but it is reliable and suitable for buildings of several floors.

To make a strip foundation for a house made of timber, you will first need to mark the site and prepare the site for construction. To do this, select a suitable place on the site with a flat topography and remove the top layer of soil from it. Then the boundaries of the foundation are marked with pegs driven into the corners and a fishing line is pulled between them.

A trench is dug along the marked contour. Its width should exceed the planned thickness of the house walls by 10 cm. Before starting excavation work, it is recommended to measure the diagonals of the future foundation; if they coincide, the markings are done correctly.

Further work is performed in the following sequence:

• The bottom of the trench is leveled, checking the level, and a layer of sand 10-15 cm thick is poured onto it. The sand cushion is watered, thoroughly compacted and leveled.
• The formwork is being constructed. It will allow the concrete to harden into a specific shape and is usually made from durable plywood or edged boards. The formwork panels are connected with nails, bending their ends outward, and the structure is reinforced in the corners with self-tapping screws. The inside of the formwork should be lined with roofing felt and secured with a construction stapler. Thanks to this, the walls of the base will be even and smooth.
• The reinforcing frame is laid. To do this, two reinforcement bars with a cross-section of at least 1 cm and a length equal to the length of the trench (if there is no material of such length, the rods are connected by welding) are placed at the bottom of the formwork. Then crossbars are secured between them with wire. Vertical pieces of reinforcement are attached to the resulting bottom row of the frame in the corners, and the longitudinal rods of the top row are attached to them. The upper tier of the frame is also equipped with cross members.

Made

It is a type of tape. But the difference between it and the monolithic foundation described above is that the prefabricated foundation is not filled with mortar, but is laid out from special concrete blocks. Therefore, such a base is also called a block base. Its construction also begins with digging a trench of the required size, the bottom of which is compacted and covered on top with a cushion of small stone or crushed stone. Then the blocks are laid inside, fastening them with cement mortar.

Sometimes, even with the correct calculation of the need for material, during the construction of the foundation there remains a gap into which the whole block does not fit. The standard way out of this situation is to shorten the block to the required size or, if the free space is small, fill the opening with bricks and pour concrete mortar.

It is easier to make a prefabricated foundation for a house from timber than a strip one, since the construction of formwork is not required. In addition, you won’t have to waste time waiting for the solution to harden. But there is also a minus - the joints between the blocks are sensitive to dampness, which is why it is impossible to build houses on such a foundation in areas with wet soil. It is also necessary to take into account the fact that the prefabricated base is less reliable and can sag when the soil swells, so it is not recommended to install it on soft clay soil.

Columnar reinforced concrete

The columnar base consists of free-standing supports located at the corners of the house and at the intersection of the walls. Such a foundation is suitable for a one-story house made of timber, a bathhouse or other lightweight buildings and is cheaper than a strip foundation. Another plus is the suitability of a columnar foundation for installation on easily swelling soil. The disadvantage is the lack of a basement in a building built in this way.

Stages of construction of a columnar reinforced concrete foundation:

• In the corners of the future building, holes are dug with a depth to the level of soil freezing and a width that allows the installation of support pillars. Usually they are asbestos-cement pipes with a diameter of at least 20 cm. In the spaces between the corner pillars and along the load-bearing walls, the same holes should be prepared for additional supports every 2-3 m.
• At the bottom of the pits, pour a 20 cm thick cushion of sand moistened with water.
• The pipes are cut with a grinder to the required length - 40 cm more than the depth of the pits.
• The supports are placed in the pits, having previously been wrapped in roofing material.
• A layer of crushed stone (about 50 cm) is poured into the space around the pipes, the supports are leveled and the holes are filled to the top with concrete mortar.
• Reinforcement of supports is carried out. To do this, 2-3 reinforcement bars are inserted inside the pipes and the cavity is filled with concrete. All you have to do is wait for the solution to harden and the foundation is ready.

When making a columnar foundation for a house made of timber with your own hands, it is advisable to equip it with a base that protects the subfloor from dampness and accumulation of debris. The idea is to connect the foundation pillars with a partition. It is made of blocks, bricks or rows of flat slate reinforced with concrete mortar. In our example we will focus on the latter option.

The construction of such a base begins with digging a trench around the perimeter of the house 30 cm deep and 10 cm wide than the diameter of the supports. Its bottom is covered with a layer of crushed stone (about 15 cm) and the remaining space is filled with concrete. Immediately after pouring, sheets of flat slate are installed into the trench on both sides so that the inner row fits snugly against the support pillars. The height of the sheets should be at the same level as the supports.

Holes are drilled at the points of contact between the material and the supports, after which the structure is fixed with self-tapping screws. The top edge and corner joints should be reinforced with a metal corner.

Also, the foundation for a house made of timber, made by yourself, needs ventilation. To create vents, holes are cut out in the material and pieces of pipe, possibly plastic, are inserted into them. The diameter of the vents is usually 10-15 cm.

Then expanded clay is poured into the space between the sheets of material, leaving a margin of 5 cm to the top edge. The base is filled with concrete mixture on top of the expanded clay. The final, although optional, stage of work is the construction of a stone or brick blind area 1-1.5 m wide around the perimeter of the house.

Sandy

If the building is very small, you can get by with an inexpensive and easy-to-implement sand base. It is installed on non-heaving, well-drained soil.

How to make a sand foundation for a house made of timber? To do this, you will need to mark the contours of the base, remove the top layer of soil and dig a trench 70 cm deep. Layers of sand 15 cm thick are poured onto the bottom of the hole, abundantly moistening and compacting them. Then comes the final final 30-centimeter layer of gravel filled with concrete mixture. After the solution has hardened, the foundation is ready and you can proceed to installing waterproofing.

Technology for laying the first row of timber on the foundation

When creating a foundation for a house from 8x8 timber (the most convenient size for planning rooms), Special attention are given to the first row of timber, the so-called crown of the building. Whether the walls will be smooth depends on the correct placement of it, so all work should be done carefully.

The primary task is to install waterproofing. It consists of roofing felt laid in two layers and one layer of glass insulation. During the installation process, it is necessary to control the horizontality of the waterproofing layer; the height difference over the entire area of ​​the foundation should not be more than 1 cm. In case of significant deviations, the material is leveled with a solution.

Crown assembly

To increase the durability of the structure, 1.5 cm thick slats treated with an antiseptic solution are attached on top of the waterproofing every 25-30 cm. The first layer of timber is mounted on top. The material should be smooth, without knots; it is advisable to take timber with the highest density of annual rings. Before laying, the wood is impregnated 2-3 times with liquid bitumen mastic, leaving the ends clean to allow excess moisture to escape.

The processed material is placed on the slats, and the voids between the timber and the base are filled polyurethane foam. You can fix the first crown with anchor bolts, but this is not necessary, since the weight of the building will not budge the frame.

At the corners, the beams are joined at the ends, so that if repairs are necessary, it is possible to do without dismantling the corners of the house. At the junctions of the partitions, the connections are reinforced with metal plates.

When making a foundation with your own hands and tying under the timber, regularly check the geometry of the building using a level and a measuring tape. All angles must be equal to 90º, and the diagonals must be the same. If everything is done correctly, the walls will be smooth and the building itself will be stable. Good luck!

In most cases, when we talk about the foundation, it means.

It is the most common and has an optimal combination of performance qualities and cost-effectiveness of construction.

In addition, strip bases have a lot of design options, which expands their capabilities and allows you to choose the most successful option.

Such qualities have made the tape a recognized leader among all alternative options.

Despite some negative aspects, this type of foundation is the most preferable for buildings for various purposes, especially for private houses.

Characteristic feature wooden houses is light weight. The material has excellent heat-saving properties, so creating thick walls is impractical.

In addition, the specific gravity of wood is significantly less than that of brick, concrete or other dense material.

Therefore, the load on the foundation is significantly reduced, which makes it possible to use a lightweight version of the foundation.

Suitable for a house made of timber:

The first option allows you to get a fairly reliable foundation, making do with less excavation and construction work. At the same time, there are some limitations associated with hydrogeological conditions, complex soil composition, the presence and depth of groundwater.

The second option requires a lot of labor and money, so for log houses it is considered irrational and is used only in difficult conditions.

It is impossible to unambiguously determine the most successful type of foundation based on the material of the walls. It is necessary to consider the specific conditions and factors influencing the choice of tape type.

Shallow strip foundation

A shallow strip foundation differs from classic version shallow depth of immersion into the ground. The traditional type requires immersion to a level below the freezing point. This requires creating a trench 2 m or more deep.

Increases the size of the tape, automatically increasing the consumption of building materials and money. Shallow foundations are immersed to a relatively shallow depth, not exceeding the freezing level of the soil.

The option is attractive, but it can create problems with frost heaving, so it is necessary to first study the hydrogeological situation on the site, find out the depth of groundwater, explore the composition of the soil and other data.

However, for light buildings, the use of a shallow strip foundation is considered the most rational solution.

How to choose concrete

The optimal choice of material is M300 concrete. Heavier grades are used for multi-storey residential or industrial buildings. The use of less dense and durable grades is impractical, since practically no savings or advantages are achieved, but the margin of safety of the base disappears.

Therefore, in practice, no one thinks about the choice, using a proven and reliable option.

Laying depth

Shallow foundations are usually immersed to a depth of 40-70 cm. This is an average value, but in practice it is necessary to consider the composition of the soil, heaving loads and other criteria. The more negative factors, the deeper the tape should be immersed.

At the same time, it is necessary to take into account the magnitude of frost heaving, which creates high loads on the side surface of the tape and forces the foundation to be strengthened. Sometimes the solution to the problem is to reduce the base, reducing the loads and balancing them along the entire length of the belt.

It is also necessary to take into account the size of the base, which is recommended to be at least 30-40 cm.

General installation diagram

Work progress in order:

1. Preparing the site, removing topsoil and leveling the surface.
2. Marking the trench.
3. Digging a trench to a specified depth.
4. Backfilling the sand cushion.
5. Installation of formwork.
6. Creation of an armored belt.
7. Concrete pouring, curing.
8. Completion of work.

Procedure for creation strip base almost never changes, which makes it more understandable and increases the reliability of the result.

Width of strip foundation for timber

The width of the tape is the value that requires. The methodology and specifics of this event do not allow obtaining correct results without experience and preparation. Contacting specialists is the best option to resolve the issue, but this will require a certain fee and will take an unknown amount of time.

Usually the issue is resolved by using online calculators, obtaining quite high-quality calculations, or they act “like everyone else,” taking the width of the tape at least 10 cm larger than the thickness of the walls. In any case, it is not recommended to make a tape narrower than 30 cm, since additional loads may appear during operation.

It is also possible to change hydrogeological conditions, which requires a certain margin of safety and stability.

Waterproofing

Waterproofing is carried out in order to cut off moisture from the concrete strip. This will save it in in good condition, prevent the destruction of the material by frozen water in winter. Waterproofing also helps improve the microclimate in the house and prevent walls from getting wet due to capillary absorption.

For a house made of timber, this is very important, since the wood is prone to rotting, which makes waterproofing treated with increased responsibility.

• Vertical. It is applied to the side surfaces of the tape, both outside and inside. Are used different materials- impregnations, coatings, rolls, etc.
• Horizontal. A lower waterproofing is used, separating the sand from the tape, and an upper waterproofing, separating the concrete and wood. Most often, in both cases a double layer of roofing material is used.

Choosing concrete and reinforcement

For a shallow strip foundation, you can use a lighter type of concrete - M200. At the same time, there will not be a significant difference in cost, and the strength of the tape will be lower than when using optimal option- concrete grade M300. The foundation is a critical element of the building, which requires the use of the most reliable materials.

The choice of reinforcement is determined by the width of the tape. In practice, they usually proceed from the ratio of 30 cm width - 12 mm diameter of the rods. Accordingly, 40 - 14, 50 - 16, etc. Usually there are no problems, but for those who want to clarify their choice there is an option.

The cross-sectional area of ​​the tape is calculated. The total cross-sectional area of ​​the reinforcement is 0.1% of the ribbon cross-section. The resulting value is divided by 4 or 6 (the number of working rods in the arm belt). After this, the most suitable diameter of the rods is determined from the SNiP tables.

NOTE!

You can use thicker rods, but you should not choose thinner rods.

Pillow under the foundation

Sand and gravel preparation performs drainage and leveling functions. The bottom of the trench does not have an ideal surface, so a layer of backfill allows you to obtain a horizontal and level supporting platform for pouring the tape.

Water entering the layer passes into the lower layers and is either absorbed into the soil or removed through the drainage system outside the trench.

The standard backfill option is sand preparation 10-15 cm thick, a layer of fine crushed stone 10-15 cm and a surface leveling layer of sand. Pure river sand that does not contain organic inclusions is used.

Each layer is carefully compacted to maximum density. The criterion for determining the quality of compaction is the absence of shoe marks when walking on the backfill.

Installation of formwork

Formwork is a form into which concrete is poured. It is assembled from edged boards 25-40 mm thick. The shields are made outside the trench, but in close proximity to it for ease of carrying and installation.

The assembled panels are lowered into the trench, aligned along the axes and secured with spacers. They determine the width of the tape. From the outside, the panels are fixed with vertical strips driven into the ground, and stops are also used to ensure the formwork remains stationary when pouring concrete.

Reinforcement

The specificity of concrete is its lack of resistance to axial tensile loads. The material is capable of withstanding enormous pressures, but when the load vector changes, it immediately breaks. To strengthen the tape, an armored belt assembled from metal ribbed rods is installed inside.

The frame consists of horizontal (working) and vertical (auxiliary) rods. The working rods perform the functions of an armored belt, ensuring the integrity of the belt and taking on all the loads.

Vertical reinforcement is needed only to support the working rods in the desired position until the concrete is poured, so its thickness is less. The use of smooth rods is allowed. To assemble the frame, a special soft wire is used, but welding is also allowed.

Fill

You can mix concrete yourself, but this is a very labor-intensive and time-consuming task. It is easier and more correct to purchase the required amount of ready-made concrete, which will be delivered directly to the site and poured from a mixer.

The quality of the material produced using industrial equipment will in any case be higher than that of home-made concrete. It is also more convenient to do the pouring from a mixer, as it is faster, which will result in uniform quality of the concrete strip in any area.

You cannot pour concrete in one place, hoping that it will spill throughout the formwork. You need to approach it from different points and pour the material evenly. This will allow you to obtain a casting with the same properties.

After pouring, it is necessary to water the casting with water every 4 hours for 3 days, and then, for a week, three times a day. The formwork can be removed after 10 days, but final hardening will occur after 28 days.

Final works

Completion of the work consists of applying waterproofing, filling the sinuses and other work with the finished tape. In addition to waterproofing, insulation for the foundation (corresponding brand of EPS) is often installed.

To fill the sinuses, it is best to use clean sand to ensure the absorption of water and its prompt removal through the drainage channel.

Useful video

In this video you will learn how to lay a strip foundation for a wooden house made of timber:

Conclusion

The construction of a private house from timber allows the use of a lightweight version of the foundation - a shallow strip foundation. With sufficient load-bearing capacity, it provides significant savings in all areas - money, labor, working time.

The resulting result is completely ready to perform its functions and is capable of providing reliable and durable support for a timber-framed private house.

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Despite the appearance large quantity building materials, timber remains one of the most popular for low-rise construction. This is due to the high thermal stability, accessibility and beautiful appearance of the material. In addition, the low weight of the finished structure allows you to save not only money, but also time on the foundation. In the article we will look at what kind of foundation is needed for a house made of timber, and how to make it yourself.

What to look for when choosing a foundation for a house made of timber

Wood is considered a lightweight material, and unlike brick buildings, all types of foundations are suitable for a house made of timber. The main thing is to carry out geological exploration of the soil before design in order to take into account a number of factors that influence the choice of material for the foundation.

• Relief of the site. If the site has strong differences in height, then the easiest way is to make a pile-screw foundation;

• Level of soil freezing in winter. When arranging a foundation with piles (concrete or screwed), they must be buried below the freezing level so that in the spring, during seasonal heaving of the soil, the foundation does not rise;
• The presence of underground rivers or the general groundwater level. If the site is located in a lowland, swampy area, then a slab foundation is often poured under a timber house;
• Financial opportunities. If you plan to make the foundation for a house made of timber yourself, this will greatly influence the choice of its type. So, most in a simple way will be the installation of a columnar base.

Next, they begin to design the foundation for the house made of timber. At this stage, the number of floors of the building is taken into account, and, consequently, the weight that will exert pressure. Added to this is the weight of the snow cover on the roof in winter.

What kind of foundation is needed for a house made of timber?

Professional builders for houses made of timber up to 3 floors recommend choosing a columnar, pile or strip foundation.

Do-it-yourself columnar foundation for a house made of timber

This type of foundation has been used for a long time. It has established itself as a reliable, easy-to-use and inexpensive foundation. Excellent for country houses and residential buildings low-rise buildings made of wood.

• Pits are dug under the supports, the depth of which should be below the freezing level.
• Place them in the corners of the house and under load-bearing walls. The distance between the pillars should not exceed 1.5 - 2 m, it depends on the weight of the house. The heavier the structure, the shorter the distance.
• A 10 cm layer of sand is poured onto the bottom.
• The formwork is made in the form of a box without a bottom of the required size. They lower her into the pit. Reinforcing bars are installed inside.
• Fill with concrete and cover with film on top. After a few days, the formwork can be dismantled, and the part of the concrete support that is on top can be treated with liquid bitumen.
• Subsequently, roofing material is placed on each post and the first row of timber is laid on top.

Do-it-yourself pile foundation for a house made of timber

This foundation is becoming increasingly popular. This is a universal and inexpensive way to make a base for a wooden house. It is suitable if the site has a strong slope. Screw piles You can screw it yourself. In addition, piles are inexpensive.

When using special auto equipment, the piles are tightened even in winter. This saves time because you don’t have to wait for the soil to thaw and dry out.

Stages of work

• At the construction site, markings are made for the pile foundation. The distance between supports for a residential building should not exceed 1.5 m. Under wooden sauna or outbuilding, a step of 2-2.5 m is allowed.
• They are located around the perimeter of the house, under load-bearing walls and always at the intersection of load-bearing and internal walls.

• They are also screwed to the depth of soil freezing. The piles are hollow, so when they are screwed in and the excess is cut off, it is recommended to fill the cavity with cement mortar.
• After a few days, when the concrete has hardened, all the piles are connected with a grillage. It will serve as the first row for laying the timber and will connect the entire foundation into a single whole, giving it rigidity.

Strip foundation for a house made of timber

This is a universal foundation, suitable for the construction of low-rise buildings from any type of material.

Its main drawback is the complexity of the work and the high price. A turnkey strip foundation measuring 10x7 m will cost approximately 100 tr. By doing the work yourself, you can save a lot, but you will have to do a very large amount of work. Besides, this type foundations are rarely made in areas with strong elevation differences. Since the construction of the basement floor will require a lot of concrete.

Stages of work

• First you need to calculate the thickness of the foundation and its depth.
• Since the house is built from timber, the width of the strip base is 15 cm wider than the timber.
• In order not to complicate the work and not to make a deep foundation, a foundation pit is dug to a depth of 50 cm. And every 1.5 meters, wells are drilled below the freezing level. Thus, a pile-strip foundation is obtained. This will protect the light wooden house from seasonal soil heaving.

• Formwork is constructed along the perimeter and under the load-bearing walls. In the future, it will be dismantled and the material required for its manufacture can be reused.
• A sand cushion is poured onto the bottom and water is poured over it to compact it.
• Reinforcing bars are placed vertically in the wells. And along the length of the tape, reinforcement is knitted in the form of a rectangle. It is advisable to use fiberglass reinforcement, as it is not subject to corrosion.
• It is advisable to pour the entire foundation at the same time. Therefore, builders recommend ordering the mortar in machines in order to avoid the long pauses that occur when mixing the mortar yourself in small batches.
• The top of the freshly poured foundation is covered with a film to prevent too rapid evaporation of moisture and further cracking of the concrete.

Insulation of the strip foundation of a timber house

Despite the thickness of the strip foundation, in winter it will partially freeze, which is why the underground temperature will be below freezing. In addition, the structure of concrete is porous and when moisture is absorbed, which expands in winter, microcracks occur, leading to the destruction of the base. Therefore, as soon as the foundation is made, it is required to immediately insulate it.

The material for insulating the foundation and basement is chosen to be slab and moisture-resistant. These include polystyrene foam and extruded polystyrene foam. The second one is higher, but it has a denser structure and is not susceptible to damage from rodents.

Advice: today there are a number of materials designed for foundation insulation. It has not only a thermal insulation layer, but also a decorative cladding like brick or stone. In addition, such materials are made in the form of panels with a locking connection, which not only simplifies installation, but also eliminates the formation of cold bridges.

Stages of work

• First, the entire foundation is treated with liquid waterproofing, bitumen, mastic or primer.
• When it dries, begin installing the insulation. Apply a sheet of penoplex and measure out the desired size. It’s convenient to cut off the excess with a stationery knife with sharp blades (they get dull pretty quickly on polystyrene foam, so you need to have several replaceable blades).
• It is attached to the foundation using a hammer drill using dowel-nails with wide heads, which are called “fungi”.
• If gaps form between the sheets, they are filled with polyurethane foam.
• At this point, the work on insulating the foundation is completed. All that remains is to make the decorative cladding. Can be mounted on polystyrene foam fake diamond or get by with an economical option - sheathe it with corrugated sheets or siding.

Insulation of a columnar or pile foundation of a timber house

For thermal insulation, you can use any slab insulation, on top of which the finishing cladding will be made. Or use ready-made sandwich panels consisting of thermal insulation and decorative cladding. But before this, preparatory work will need to be done.

• Concrete or brick pillars are coated with liquid bitumen waterproofing, the piles already have an anti-corrosion coating.
• Both of these foundations are single columnar foundations. Therefore, to insulate them, you will need to make a frame. It is made from wooden slats around the entire perimeter. The distance between the slats is calculated individually based on the size of the insulation material.

• Expanded polystyrene is most often used. Its choice is justified by its high heat-retaining characteristics; it does not change its properties under the influence of moisture, does not rot, and is not spoiled by rodents.
• The sheets have different thicknesses. So, for the foundation it is recommended to choose them with a thickness of at least 40 mm. All polystyrene foam manufacturers produce sheets using a tongue-and-groove system so that there are no gaps left after installation. But if the sheets were not able to fit tightly during fitting and cutting, the joints are foamed with polyurethane foam.

Already in this form, the foundation of the house is reliably protected from adverse effects. environment. But foam, and penoplex itself, require protection.

• Various materials are used for finishing. The cheapest way is flat corrugated sheeting. It is chosen to match the color of the roof. Mounted on roofing screws with rubber gaskets.
• A more expensive option is façade panels imitating stone or brick. They are sold together with additional elements to beautifully go around all the corners and protrusions. Most of these panels already have a thin thermal insulation layer, so it is possible to attach them directly to the frame.

• The most expensive option is finishing natural stone. It is attached to the cement mortar directly onto the Penoplex. In this case, the frame must be made of high-quality material, preferably from metal guides, so that they can withstand heavy weight natural material. Also, using stone to finish the foundation, it is also laid on the blind area, covering the concrete.

What kind of foundation is needed for a house made of timber video