Which foundation is best to use for a timber building? Foundation for a house made of timber: instructions for construction What kind of foundation is needed for a house made of timber

Upon completion of all preliminary calculations, implementation of the project, obtaining permission and preparing the site for the construction of the building, perhaps the most important stage begins, errors at which are unacceptable, since they are almost impossible to correct. We are talking about building a foundation for a house made of timber - not only the durability of the building, but also its safety largely depends on its reliability. What is the best foundation for a house made of timber and how to build it?

When building the foundation of a house from timber, remember that all the loads from the structural elements fall on it. The structure of a house made of timber has less weight than a brick or stone building. Consequently, the requirements for the load-bearing capacity of the foundation of a log house are somewhat underestimated.

Even before making a foundation for a house made of timber, you should anticipate possible errors that usually occur during construction. Of course, you need to do everything possible to avoid them in the future. It’s better to play it safe by taking the time and effort to carefully design.

The choice of foundation for a house made of timber is carried out taking into account the characteristics of the building’s structural system, the magnitude of the load and the ability of the soil to withstand it.

There are several types of foundations for houses made of timber, depending on the design features: strip, pile, slab and columnar.

When deciding what the foundation for a timber house will be, it is important to take into account factors such as soil type, groundwater level, operational loads and soil freezing depth. Based on these data, it is decided what the base area and foundation depth will be.

In addition, when choosing which foundation to pour under a timber house, the nature of the loads and the duration of their action are taken into account in advance. As you know, they can be permanent or temporary. The weight of the structural elements of the structure, as well as furniture and residents, is classified as permanent loads, and the loads created by snow cover and wind are classified as temporary.

Columnar foundation for a timber house

A columnar foundation is suitable for a house made of timber without a basement, which has a lightweight structure. In the vast majority of cases, a columnar foundation is used in the construction of a cobblestone house. The main advantage of a columnar foundation for a house made of timber is its cost-effectiveness: load-bearing floor beams are installed on separate pillars, the construction of which requires little consumption of building materials. A columnar foundation is made of wood or stone (brick).

The wooden columnar foundation of a timber house is erected in the form of so-called chairs, which are installed in pre-dug trenches in a strictly vertical position. In order to increase the load-bearing supporting area of the pillars, as well as to give them stability, the chairs are supported with their lower ends on a concrete slab or flat stone.

Often, a special cross with struts made of wood is used for this purpose. If concrete is used to secure the pillars, the installation of the supports should be carried out at the stage of pouring the concrete solution into the trench. In this way, the strength of the foundation can be further increased.

The next step after pouring the concrete mass into the pit is filling it with sand and layer-by-layer compaction.

The undeniable advantage of a wooden columnar foundation for a house made of timber is its relative cheapness and ease of implementation. Its construction does not require any special skills.

How many columnar foundations need to be made depends on the area and weight of the building. The main criterion during calculations is the bearing capacity of the soil and the total weight of all materials that will be needed to build the house. Columnar foundations, this should be remembered, must be installed both at the corners of the structure and at the intersections of walls.

A do-it-yourself columnar foundation for a house made of timber, made from stone, is not only strong, but also durable. It is made using the rubble masonry method; dressing the seams during work is required. For the construction of stone pillars, rubble or granite stone and brick are used. In the latter case, they take iron ore brick, since sand-lime brick, as well as ordinary red brick, are not suitable for this purpose.

In areas with heaving soil, it is advisable to build a columnar foundation with your own hands under a timber house made of concrete. Thanks to the constructed support heel, the ground does not rise, and the building remains reliably protected from the destructive effects of water freezing in the ground.

It is advisable to build a monolithic columnar foundation on low-moisture soil. Sand cushions should not be used in trenches as this may result in uneven distribution of the aggregate during compaction.

Before pouring such a foundation for a house made of timber, cement milk is usually poured into the well, after which reinforcement made of metal rods welded together into a frame is placed in the trench.

During installation of the reinforcement, care must be taken to ensure that it does not touch the ground. The above actions are especially relevant when performing work on soils with low bearing capacity.

Before filling the trench with concrete, the lower boundary must be marked on the ground. To do this, use a level or hydraulic level. Concrete is laid in layers, periodically compacted and bayoneted.

After filling the cavity, a so-called roofing felt jacket is placed into the well. When the soil heaves, it protects the foundation from the negative effects of the soil.

For a house with a basement and a ground floor, a columnar foundation is not suitable. It is not erected in an area where there is a significant difference in height, since in such conditions it is unstable and susceptible to destruction.

When excavating a pit, you should not take long breaks, otherwise, as a result of the action of atmospheric moisture, the bottom will be washed out and the walls will collapse.

Types of foundation for a house made of timber: slab and pile (with photo)

A slab foundation is the best for a timber house built on an area with a high groundwater level or weak bearing capacity of the soil.

It consists of a monolithic reinforced concrete slab, which is made directly on the construction site. To strengthen the slab, a reinforcement frame made of wire or pipes or metal rods is used.

On highly mobile soil, pile foundations are erected under a timber house. Piles can be hanging or made in the form of racks. In individual construction of low-rise buildings, their length is 4-6 m. The purpose of rack piles is to transfer the load from all structural elements of the house to the lower, most stable layers of the soil. Whereas stand piles are completely in the ground, friction piles hold the structure above the ground. Before installing them, the soil is thoroughly compacted. When constructing a pile foundation for a house made of timber, screw piles can be used, which are screwed into the ground like screws.

Strip foundation for a timber house

Strip foundations for houses made of timber are most often used. There are two types: monolithic and prefabricated. Its width depends on the expected load on the strip foundation. In addition, when building such a foundation, it is necessary to take into account the properties of the foundation soil. If the house has a basement or ground floor, the strip foundation can serve as the walls of the room.

Concrete blocks are used for a prefabricated strip foundation for a timber house. However, this type of foundation is not suitable for houses with a basement, since horizontal and vertical seams between the blocks prevent the penetration of moisture, and high-quality waterproofing will require significant funds.

Blocks for prefabricated strip foundations are produced in standard sizes, with a fixed thickness - according to the width of the foundation.

Before pouring such a foundation under a timber house, at the initial stage a concrete pad is made (usually 10 cm thick). Then the first row of blocks is made, a layer of cement mortar is applied on top, after which the second row of blocks is installed. Vertical seams are carefully filled with mortar. The blocks are mounted with dressing: the seams between the blocks of the first row do not coincide with the seams of the second row. Bandaging is observed in areas adjacent to both external and internal walls. The blocks are installed on slabs 80-280 cm wide if the bearing capacity of the soil is insufficient.

Correct calculation when choosing the optimal foundation for a house made of timber

Depending on the type of soil, the base area is calculated so that the load does not exceed a critical value, which is expressed in kilograms per square centimeter. There are several options for calculating the foundation for building a house made of timber.

Crushed stone, gravel and pebbles, coarse soils: medium density - 5 kg/cm2, dense - 6 kg/cm2.
Hard and plastic clays: medium density - 1-3 kg/cm2, dense - 3-6 kg/cm2.
Wet sands: medium density - 2 kg/cm2, dense - 1.5-2.5 kg/cm2.
Fine sands: medium density - 2.5 kg/cm2, dense - 2-3 kg/cm2.
Medium sand: medium density - 2.5 kg/cm2, dense - 3.5 kg/cm2.
Coarse and gravelly sands: medium density - 3.5 kg/cm2, dense - 4.5 kg/cm2.

Under the influence of loads in the first years after the construction of a house, the soil contracts, resulting in soil settlement. Uneven settlement leads to the appearance of cracks and various types of deformations. Thus, the bearing capacity of the soil is determined by the magnitude of the load together with the settlement, which does not exceed the established standards.

When calculating the loads on the foundation of a timber house, the specific gravity of the foundation materials is taken into account first. It is expressed in kilograms per cubic meter.

Since not all soils have sufficient strength, and most of them are compressed, the depth of the foundation built on them can be different.

The depth of laying the correct foundation for a house made of timber on an area with non-heaving soil should be at least the depth of soil freezing (about 2 m). Having chosen the optimal foundation for a house made of timber, it is laid below the freezing line of the soil.

How to make a foundation for a house made of timber with your own hands: (with video)

Step 1

Before making a foundation for a house made of timber, the area is studied. If there is a significant difference in elevation, the top layer of soil is removed. The house plan is then completed and cast-offs are installed. With their help, you can mark the boundaries of the foundation.

Two nails 60-80 mm long are driven into the horizontal strip of each of them at a distance of 40-42 cm from each other. The first pair of cast-offs is fixed in the ground towards one of the sides of the future house - at a distance of 8-10 m from each other.

A two-branch cord is pulled and secured with nails. The remaining cast-offs are installed in pairs in the same way.

The cords, stretched lengthwise and crosswise, form an angle of 90°. They are lines indicating the boundaries of future trenches. The contours of the trenches are transferred to the ground. Pegs are driven in in the right places, which, together with a cord stretched over them, will mark the internal and external boundaries of the trenches.

Step 2

Next, before pouring the foundation for a house made of timber with your own hands using a shovel, the soil is cut strictly along the cord, then it is selected to a depth of 20-25 cm. After this, the equipment is removed and a trench is dug to a full depth of 80-100 cm. The selected soil is transferred to another end of the area.

Excavation of soil is carried out carefully, since in the future the foundation will need to be compacted and then formwork constructed. According to the house design, the necessary communications are carried out.

Step 3

A pillow for the foundation is being made. To do this, a thin layer of clay is poured onto the bottom of the dug pit and rubble stone is placed. As an option: one third of the trench is filled with clay. The sizes of the stone vary from 15 to 30 cm in diameter. Remember: The larger the rubble stone, the stronger the foundation. A layer of gravel is poured, then sand.

It is better to lay gravel and sand in trenches in layers 15 cm thick, wetting each of them with water and compacting them. The last layer of sand is filled with water. Sand and water will fill the space between the soil and the stone. If necessary, add sand on top. The pillow becomes denser.

Step 4

Next, to make a foundation for a house made of timber, wooden formwork is performed. The material for the frame is boards with a section of 22 X 100 mm and beams with a section of 50 x 100 mm or formwork plywood.

It is best to use lumber with wane. Nails 60-100 mm long can be used as fasteners.

Fastening piles are driven into the foundation line. They are located so that no obstacles are created during the construction of the formwork. The distance between them is on average 1.5-2.5 m.

Installation boards with a cross section of 22 X 100 mm are nailed to the piles. Connections are made using nails: they secure the boards well, preventing them from moving arbitrarily. In this case, the formwork should be located on the line of the trench.

Step 5

Using a plumb line, the locations of the boards for the formwork surface are determined on the installation boards. Marks are made.

The lower purlins are attached to the installation boards with nails. The sheathing is nailed to the inside of the lower purlins. Its upper surface should be almost at the same level as the upper surface of the future formwork. The sheathing posts are installed. The distance between them should be approximately 30 cm. The rear pillars of the formwork are made. To do this, on the outside of the lower girder, in the places where the installation boards are located, racks are attached, the height of which is 10-12 cm greater than the height of the internal ones. The top purlin is attached to the posts.

Here you can watch a video of building a foundation for a house made of timber:

Building a foundation for a timber house with your own hands (with video)

Step 6

Using a level or a leveling cord, marks are made on the internal posts that indicate the height of the foundation. The formwork boards are attached to the internal posts with nails. The edge of the topmost boards should coincide with the marks made. The distance between the nails of the lower boards can be slightly increased - within 0.5-1 cm. The height of the formwork should be at least 40 cm. After checking the verticality of the outer and inner sheathing, corner supports are attached.

Using a ruler or tape measure, check the width of the future foundation in the upper part, and attach horizontal ties at the top of the formwork.

Mount the corner supports of the internal sheathing. Check all corners of the finished formwork and, if necessary, strengthen them with additional supports and ties.

The inner surface of the formwork is protected with roofing felt. This way you can avoid contaminating the boards with cement mortar.

Step 7

Next, when building a foundation for a log house with your own hands, they begin to construct the reinforcement frame. For work, prepare straight rods and spirals with a diameter of 3 mm, made of baked wire.

Straight rods can have a periodic profile. They are made from smooth wire with a diameter of 8-10 mm, angles or pipes. It doesn’t matter what material you use, the main thing is that the cross-sectional area of the straight rods in both the top and bottom rows is greater than 8 cm2.

Using plywood, metal corners and wire, assemble a wooden frame - a device with which you can easily make a spiral for reinforcement.

The width of the frame should be 6 cm less than the internal width of the formwork (the distance between the formwork boards on the inside).

A spiral for reinforcement is being manufactured. To do this, a wire is carefully wound around a wooden frame.

Where it bends, a right angle is knocked out. To reinforce one side of the foundation, which is 6 m long, you need to make 14 turns. Having removed the wire from the frame, it is pulled into a spiral in increments of 0.5 m.

To further protect the foundation reinforcement from various types of influences, the spiral must be placed in the formwork in the center, leaving free space, which is subsequently filled with concrete.

Step 8

Straight rods are inserted into the spiral, forming the bottom row. Use 2 or 3 rods, depending on their thickness.

Wire twists are used to secure the rods in a spiral. In a similar way, 2-3 rods are fixed in the upper part of the spiral - the manufacture of the reinforcement cage for the foundation is completed. The reinforcement frame is placed in the formwork.

A concrete solution is being made. To do this, the ratio of its components - cement, sand and crushed stone - is calculated. Remember: to get durable concrete, aggregates must be taken without clay admixture.

If necessary, sand and crushed stone are washed, and a container with water is prepared. A container for concrete is installed next to the formwork, into which 1 bucket (10 liters) of cement and 1.5 buckets of sand are poured. If necessary, sand can be added. Mix everything thoroughly with a shovel until smooth. If the mixture is too thick, add water. The finished mass should not spread.

The prepared solution is laid out in the formwork in layers 15-20 cm thick. At the same time, the formwork boards are tapped on the outside, and the mixture is bayoneted to avoid the formation of unwanted voids between the reinforcement bars. Each layer is carefully leveled.

The required number of batches is carried out to completely fill the formwork with concrete.

Using pipe scraps of suitable diameter, ventilation holes are made. They are placed opposite each other along the load-bearing partition. During concreting, you need to monitor the condition of the formwork. If distortions or displacements are detected, you should stop preparing the concrete mixture and immediately begin correcting the wooden structure. This must be done before the concrete mortar begins to set.

Step 9

After 3 hours after laying the concrete, the surface is covered with a layer of sand or sawdust. In summer, the concrete surface should be watered periodically (on average once every 2 hours) for 3 days. Concrete acquires the necessary strength 7-10 days after it is laid.

A concrete blind area is made around the base, the above-ground part of the foundation. It is a platform that is arranged around the perimeter of the foundation, which has a slight slope (on average 30).

The width of the blind area is determined depending on the width of the eaves overhang of the roof. Typically the width of the blind area is 60-75 cm.

Work begins by removing the top layer of soil by digging a trench 15 cm deep. A brick fence is installed along the outer edge of the blind area, and the space between the base and the brick curb is filled with crushed stone.

Then the concrete coating is done. If desired, a drain is made along the blind area to drain water.

To protect the foundation and walls from moisture penetration, waterproofing is done. For this purpose, use bitumen mastic or glued waterproofing material - insulation, roofing material or glass hydroisol. They will need to be glued using bitumen or some other mastic in 2 layers.

The mastic is applied using a paint roller to the surface of the foundation from the outside. If the house is being built on a site with a high groundwater level, it is necessary to additionally protect the waterproofing material covered with walls made of brick.

The video “Foundation for a timber house with your own hands” shows all the stages of work:

How to waterproof the foundation of a timber house

Next, horizontal waterproofing is performed. For this, bitumen mastic and roofing felt are used. The working surface is leveled, then mastic is applied in an even layer, after which roofing felt is laid. If necessary, the edges of the material are trimmed. Knowing how to waterproof a foundation for a house made of timber, you will protect the walls from moisture that enters the foundation from the soil. In addition, if the building shrinks, the walls will not crack thanks to the waterproofing layer.

Various materials can be used as a waterproofing material for the foundation - from roll to injection.

During new construction, to organize waterproofing of a concrete foundation and wall (if it is made of beams), it is necessary to treat the horizontal concrete surface of the foundation with a solution of a special material - “Penetron”, which will create a waterproofing barrier that prevents capillary entry of moisture.

On the foundation, on top of the waterproofing layer, brickwork is made with a height of 4-6 rows of bricks. From the outside it is made solid, leaving holes for ventilation. On the inside, recesses are made in the right places for the subfloor joists. Remember: the logs must be at the same distance from each other. It must be at least 60 cm.

The subfloor logs are laid on the foundation so that their ends are in recesses made in the brickwork. The cracks are filled with polyurethane foam.

Look at the photo “Foundation for a house made of timber” to visualize how it is poured:

The foundation is the basis of any structure. The strength and reliability of your home will depend on its quality and how it was made. If it is laid incorrectly, without observing the rules and regulations, neither the façade nor even thick walls can help the construction. For a long time, great attention has been paid to the foundation; for example, the Egyptians built it only according to strict calculations. That is why it is not surprising that the Cheops pyramid still stands without distortions or obvious deformation.

Our ancestors also built their log houses, placing them on large stones, filling the gaps between them with pebbles. Today, more progressive foundation laying methods are known and used all over the world.

Choice of foundation. Its varieties

The main purpose of using a foundation is to support the weight of the building and prevent it from sagging or collapsing. Depending on the level and type of support on the ground, there are three types:

Shallow strip foundation. Experts recommend using it specifically for the construction of a house made of timber. This is due to its practicality and ease of manufacture. Pouring such a foundation occurs using a mixer, or with your own hands. You need to use only high-quality concrete grades, such as M300 and higher. When making your own foundation, it is important to properly prepare the mixture. The proportions of cement, crushed stone and sand should be 1:2:2.
Monolithic slab. Such a foundation is located under the area of the entire house in the form of a reinforced concrete slab or a structure consisting of reinforced concrete beams. It is used most often on heterogeneous soils that can move. Its installation will lead to high costs. It can be used as a foundation for a small log house, where a reinforced concrete slab is used as a subfloor.
Pile foundation. This structure consists of several piles, which are covered on top with a reinforced concrete slab. This type of base is universal and economical, but is much less common than all others. This is due to the fact that for its construction you need to use special equipment. These piles will be indispensable in areas where the upper part of the soil is mobile. You can see what this foundation looks like in the video.
Other types. In addition to the above options, today you can find both rubble and brick foundations. A rubble foundation is constructed from rubble stone and cement mortar. This construction is labor-intensive and complex, but the result will be a durable and strong foundation. A concrete foundation can also be found as a structure for a log house. In another way it is called “poured”, and it contains concrete in its pure form.

Selecting the right base will require some testing. It is definitely worth examining the composition and characteristics of the soil. It is worth considering how much the soil will freeze in winter. Thanks to such studies, it will be possible to understand what indicator of stability the soil has.

In addition, it is worth finding out at what depth the groundwater is located. During the construction of the foundation, it is necessary to ensure that the level of these waters is located significantly lower than the level of soil freezing. Also, when choosing a base, you should definitely take into account the area of the building.

Marking for the foundation on the site

Scheme of correct marking of the foundation on the site

The first step in creating a foundation with your own hands is to correctly mark it on the site. To do this, you will definitely need a project to build a house from laminated veneer lumber, simple or profiled. Without diagrams and drawings of the location of the house, it will not be possible to correctly mark the territory. It is necessary to prepare the area for marking. The entire construction site must be level.

The first step is to determine the starting point. It should be located in the location of the facade of the future house. A peg needs to be driven into this place. Then you need to measure the length along the facade, and drive the peg into the end point again. The third point is in the opposite corner of the second peg, and the fourth point is in the opposite corner of the first peg. Drive stakes into the third and fourth points as well. The end result should be a rectangle.

The next step is to accurately measure the diagonals. To do this, you need to measure the distance between corners 1 and 4, 2 and 3. The resulting indicator should be the same. If this is not the case, then using a large protractor you need to start aligning the corners. It is required to achieve ideal diagonals. When this step is done, you need to mark the location of the partitions. There can be no problem with this. The main walls are marked, now following the house design, you need to measure the required distance from them.

This work done is considered the initial marking. After its completion, you can begin the second phase of work. Why is this necessary? When the time comes to dig a pit, the previously driven pegs will get in the way, because they are located on the foundation line. To prevent this from happening, you need to prepare a cast-off. It should be positioned behind the dig line to define and show the inside base line. How professionals do this process can be seen in the video.

The cast-off must be located behind the foundation line, after which a cord or thick thread must be pulled between its elements. The cast-offs should be installed so that the cord is located on the top line of the foundation at the same level. This completes the marking process; you need to start digging trenches.

Proper digging of a foundation pit

One of the very first preparatory stages associated with laying the foundation is digging a pit. Initially, for this it is necessary to remove a layer of plant soil. The depth of this layer, which must be removed, is 20 cm. After it, another layer begins, which will also need to be removed.

If special devices are used to dig a pit, then you do not need to dig it completely. It is important to leave 10-15 cm more soil than is required to remove it manually. Thanks to this, the continental soil will be preserved, which will be in contact with the foundation.

The pits may be different. For example, narrow trenches are perfect for a strip foundation; wide trenches should be used if the house has a basement or basement. It is worth noting that when digging a wide pit, all walls must be reinforced with special slopes. They should be installed at an angle of 30°.

To select the type of pit required for a particular house, you need to invite a geotechnician. If the soil is loose, it is worth digging wide trenches and, conversely, if the soil is very dense, then narrow pits should be dug. The size of the narrow pit corresponds to the width of the base. To make all excavation work easier, you need to make the walls with a slight slope.

Sand cushion for the foundation

Sand cushion is a layer of sand located under the base of the foundation. The purpose of its use is to create a level and strong platform for laying the foundation. The main advantages of its use are the provision of optimal load on the foundation and high-quality protection against destruction of the foundation by groundwater.

A sand cushion can serve as a substitute for soil. If in the dug pit there is a layer of earth in poor condition that cannot be used for construction work, then it can be removed. Sand is placed instead.

Great care should be taken when choosing. Firstly, the grains of sand should be of medium size, neither large nor small. Secondly, the thickness of the sand cushion under the base must be at least 25 cm. After laying the sand in the pit, it must be leveled. The result should be a perfectly even, smooth layer of sand, without excess in some places. After this, the pillow is compacted. This is necessary so that the sand is not so unstable.

During compaction, the sand must be constantly moistened with water. This should be monitored especially carefully during the hot summer season. Thanks to humidity, the sand will become denser and more convenient to work with.

Installation of formwork. Choosing edged boards

In the process of creating a foundation for a house made of 8x8 timber, one of the main places is occupied by the installation of formwork. The final quality of the foundation will depend on the correct execution of this step. First, you need to decide on the material that will be used to make the formwork. The most popular edged board for this is 25x100.

Edged boards are used most often as a material for making formwork. This is due to the exact dimensions of the product, thanks to which it is possible to reduce finishing work. Because of this, there is a reduction in the overall cost of building a foundation.

An important matter is the choice of wood for the production of formwork. In this case, it is worth taking into account the magnitude of the load that is expected to be exerted on the foundation. Hardwood is very popular. They are strong and reliable, making it possible to perform the majority of types of formwork. Other nuances of choosing wood can be viewed in the video.

After choosing the material, you should start making the formwork yourself. It should be slightly higher than the height of concrete pouring. First you need to knock down the shields. The length of each of them should be 25 mm longer than the length at which it will be installed. All panels are fastened in the shape of the letter “L”, so this precaution will save material and ensure reliable fastening.

When assembling boards for a house made of timber with your own hands, it is best to use simple nails rather than self-tapping screws. After driving the nail into the board, you can bend it. This will increase the strength of the entire structure. When using self-tapping screws, they can jump out from the pressure of the concrete solution.

After assembling and fastening all the panels, it is necessary to install jumpers to the top of the formwork. To do this, you need to install wooden spacers that will strengthen the walls of the formwork. Thanks to this, it will not fall apart, and the concrete will not leak out. This completes the installation of the formwork. If after this there is an edged board left, it is better not to part with it. It will be useful for installing a subfloor.

To calculate the cost of formwork, you need to divide the sum of the lengths of all sides of the trench by 6. You get the standard length of one board. Afterwards, the height of the formwork must be divided by 0.15 (the width of the board). Round both results obtained and multiply by each other. The total will be the number of boards required for assembly.

In 1 cubic meter – 43 boards with a section of 25x100. Therefore, the resulting result when multiplied must be divided by 43. You will get a number indicating how many cubic meters. required. Approximate cost of cubic meters boards – 5500 rub.

Foundation reinforcement and ventilation

An important step is to reinforce the foundation for a house made of timber with your own hands. If this process is performed efficiently and correctly, you can increase the strength and service life of the foundation. The base must be reinforced immediately after the formwork has been installed. To do this, you will need to use metal rods, the cross-section of which does not exceed 10mm.

Using them you will need to build a grid. Its width should be slightly smaller than that of the pit. This is due to the fact that its installation must be carried out at a distance of 5 cm from the edges of the formwork. So, the first step is to lay the bricks on the bottom of the pit. Then place the reinforcement in the formwork. When laying, there is an important rule - the reinforcement should not come into contact with the walls of the formwork.

After completing this work for a house made of timber, you need to take care of ventilation. It can be created using pieces of asbestos pipe, and its diameter should not be less than 100 mm. Installation should be carried out at a slight angle of inclination. They need to be filled with sand in advance so that these pieces of pipe do not fall into the solution during pouring.

Preparation and pouring of the solution

In order for the strip foundation for a house made of timber to be laid, you need to make the solution yourself. Using concrete M300, you need to mix sand, crushed stone and cement in a ratio of 2:2:1. You need to add water little by little to the solution so that the resulting consistency is not liquid.

Concrete must be poured gradually. When pouring the first layer into the formwork, you need to take a tamper and walk it over the entire surface. To distribute the fill evenly along the formwork, it is recommended to tap with a hammer. During the pouring process, you should not take long breaks to avoid the formation of cold seams.

After the last layer has been poured, you need to carefully walk over it using a tamper. Thanks to this, the surface will be completely leveled. Complete hardening will occur after four weeks, and only then can the formwork be removed.

In order for the strip foundation for a house made of 8x8 timber to be of the highest quality, you need to follow the following recommendations:

The proportions of all components can be varied. For example, use more crushed stone than sand, that is, in a ratio of 4:2:1 to cement;
If the construction of the foundation takes place during the cold season, then it is better to heat the water for preparing the solution so that the hardening process goes faster;
Before laying the first crown, it is necessary to waterproof the foundation. It should be done in several layers, and the first log of the log house should be treated using a quick-acting antiseptic;
To make concrete pouring go faster, it is worth inviting help.

Foundation cost

To make a strip foundation with your own hands, you need to be prepared for many costs. It is impossible to determine its cost with accuracy, since it will depend on several factors:

Amounts of materials used. These are sand, crushed stone, cement, wood, edged boards, etc.;
From the number of devices. These are nails, self-tapping screws, screws, etc.;
Construction of a house from profiled timber and other types and its layout;
From the cost and time of renting special equipment or hiring additional labor;
On the condition of the land on which the strip foundation will be made.

A strip foundation for a house made of timber should be made following all the standards and requirements. This is a guarantee that the house will stand for a long time without deformation, bevel or destruction.

Wood was used in construction by our ancestors. Residential buildings of unique style were erected from it. Some architectural monuments built from this material still exist today. Time passed, and construction technologies gradually changed. Wood was replaced by brick, foam concrete, cinder block, etc. Only now wooden houses have regained their former popularity. They are built from different types of forest. But not everyone knows which foundation is better for a house made of timber or logs.

How to choose a foundation?

The question of which foundation is best for a house made of timber is of concern to a person who wants to build a home from this material on his country plot. After all, a solid foundation is the key to a long service life of a building. The soil on the site is of great importance. And it could be:

homogeneous;
fine-grained;
peat

An excellent option for any type of foundation is the first type of soil. To build a house on it, you will not need to be sophisticated with various technologies. The foundation in this case can be anything.

Note. On this basis, the structure will not shrink, deform under the influence of moisture and warp throughout its entire service life.

Fine-grained soils are not as practical. They can be sand or clay. They withstand any load well only in dry weather. But as soon as precipitation falls or flooding occurs, the soil immediately begins to “float.” This creates an additional load on the foundation, and for this reason it begins to deform: it changes shape and cracks.

Note. If you choose the wrong type of foundation for such soil, then over time this will cause deformation of the entire structure.

Peat soil is considered the most unsuccessful. As a rule, it can be found near forest plantations, in swampy areas, near lakes and other bodies of water.

In order to determine the type of soil on the site, special geodetic surveys are carried out. They will allow you to accurately determine which foundation is best suited for a log house. According to the report, you can find out how much of a particular component is in the soil.

It is also worth considering the level of soil freezing at a site in a certain area. After all, the depth of the foundation should be below it. This will protect the entire structure from moisture in the event of snow melting. You can set this level yourself. To do this, at the beginning of spring, when the snow melts, the surface of the soil is removed with a shovel and it is checked how deep the frozen soil is. Or you can ask a neighbor for advice or contact a geodetic service.

Types of foundations for a timber house

In order to accurately determine which foundation is best for a house made of timber, you must initially know all the characteristics of the foundations that are used for the construction of such buildings.

So, you can build:

monolithic base;
pile;
tape;
columnar;
slab

All these types of foundations differ not only in their manufacturing technology, but also in their technical characteristics. Only based on them can you determine what kind of foundation is needed for a house made of timber.

Note. First you need to find out from specialists everything about choosing a foundation for a house made of timber, so that the structure is durable and will serve faithfully for more than one generation of residents.

Monolithic foundation for a wooden house

We can say with confidence that such a foundation is the most practical and most popular for the construction of any house. Despite its advantages, it has one rather significant drawback - cost. When calculating such a base, the amount of material required is taken into account:

sand;
cement;
water;
other additional components.

The latter include hardeners and other mineral substances that improve the strength of concrete and its resistance to almost all influences.

The advantages of such a foundation

Firstly, the base has extraordinary strength. Depending on its depth, it can support multi-story buildings made of any material. Secondly, the foundation is durable. It does not have a specific service life. In some cases, even if a house is demolished, the foundation can be used to build a new one.

Advice. In this case, certain work is carried out to reconstruct and strengthen the foundation.

How to build a monolithic foundation?

Used to build this foundation for a house made of timber, instructions. So, the dimensions of the future structure are initially determined and a pit of the required depth is dug. Next, the formwork is made from wooden boards. Then you need to prepare a concrete solution. All ingredients are mixed in a concrete mixer so that the composition has a uniform structure.

Once the concrete is ready to be poured, reinforcement is laid to strengthen the strength of the base and the mortar is poured.

Note. Such a foundation must dry and strengthen. This takes at least 20 days.

Pile foundation

If it has already been determined which foundation is best for a house made of timber, we select materials for it. For example, if this is a pile foundation, then you will need piles made of wood or metal.

Important! Metal piles are considered the most durable and reliable. The material from which they are made is more resistant to various influences.

This is not to say that wooden piles will be less reliable. Rather, they are less functional, since they cannot be used on any soil.

Features of a pile foundation

The main advantage of this base is its versatility. It can be built on any soil, since the support and loads of the structure will only affect the piles.

Note. It is for this reason that it is worth taking into account the load of the future structure in order to prevent the piles from deforming.

Such components of the foundation are deepened into the ground by at least 1.5 meters. It all depends on the number of storeys of the building and its mass. Piles in a structure will be much cheaper than a monolithic foundation. Because of this, they are often chosen for the construction of wooden buildings.

First, holes of a certain depth are dug along the entire perimeter of the future building at a distance of no more than 1-1.5 m. They make bedding from:

sand;
gravel;
crushed stone

Then the piles are leveled in this hole and concreted. The solution is prepared similarly to the construction of a monolithic base. During the work, you need to waterproof the piles using roofing felt and plastic film.

This type of foundation gains strength within 30 days. After this, the top trim is made of wood or metal pipes. Only then is a frame built on the foundation, on which the walls of the wooden house are mounted.

Strip foundation and its characteristics

Which foundation is better for a house made of timber? This question cannot be answered unequivocally. It all depends on the type of soil on the site. A strip foundation is something adjacent between monolithic and pile foundations. It is made from:

small pillars;
concrete mortar.

First, markings are made and a shallow pit is dug.

Note. If the building is multi-story, then it is better to make the foundation depth 1 m.

Secondly, the pillars are installed and concreted. Formwork is built on top of them and concrete is poured. Since it is not possible to carry out all such work in one day, filling is carried out in stages.

Important. Such a foundation gains strength after a few weeks.

Columnar base

This foundation is a type of pile foundation. Only instead of piles they use concrete pillars. They can also be made of brick. Such a foundation should protrude 30-50 cm above the ground surface.

Important. Such a foundation is well suited for soils that are prone to flooding by groundwater. Due to the fact that the structure will be at a height, moisture will not cause its destruction.

What kind of foundation is needed for a house made of timber? The technology for constructing this type of foundation is quite simple. Initially, recesses of 1-1.5 m are dug. Brick pillars are laid out in them or ready-made ones are installed. Then all this is filled with concrete mortar, to which, in addition to standard ingredients, crushed stone is added.

Slab foundation

There can be any foundation for a house made of timber. Many people don’t even know which one to choose from the well-known ones. The most important thing is to first assess the technical and quality indicators of the soil and the level of soil water. The slab base is considered the least popular. This is due to the fact that it cannot be used on any soil. It does not have underground supports, and if the area is flooded, the slabs can become deformed and move. All this happens even with a good connection.

It is built on the surface of the soil with a small depression. A backfill of sand and crushed stone is first made in the designated area. They also lay insulation materials that can protect the structure from moisture and adverse climatic influences. Then the slabs are laid, the spaces between them are filled with concrete mortar. In some cases, reinforcement is used, which is laid on top of the slabs and filled with concrete.

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:

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 of installation of the support foundation for a 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.
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.
Availability of a basement or ground floor.
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.
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. The depth of groundwater and the freezing point of the soil are of great importance.

The simplest foundation for a wooden house is a columnar one.

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:

Site preparation - you need to remove the turf layer and all plants.
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
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.
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.
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
Install the formwork at the required height. For a 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.
Once the pillars are ready, you can install a grillage on them - the supporting foundation of the house.
A grillage is installed on the horizontally aligned pillar heads

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.

If you make a widening at the bottom of the pit, the area of support for the foundation will increase

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.

The foundation on screw piles is erected with virtually no excavation work

Strip foundations

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

The foundation is marked using pegs and a cord.
The marking is done so that the corner of the tape is at the intersection of the stretched cords
The soil layer and plants are removed from the working site.
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.
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
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, the formwork walls are covered with plastic film before reinforcement.
The material for formwork must be selected taking into account the possibility of its further use.
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.
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 with water. 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.

After the concrete has dried, waterproofing and the supporting frame of the house are laid on it.

Slab foundations

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

Mark the site, remove the soil layer and vegetation.
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
Cover the compacted surface with a layer of geofabric overlapping the walls.
Arrange a drainage layer of sand and gravel, level and compact it.
A drainage bedding is made in the pit and formwork is installed
Lay a layer of insulation from foam polystyrene boards, wrap the geofabric overlap.
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.
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
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.

To pour a monolithic foundation, it is better to call a special team

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:

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

It should be noted that all equipment can be rented.

Photo gallery: foundation pouring tool

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.
When concreting, you need to carefully compact the concrete and pierce it with a pin, preventing the formation of air bubbles.
Concrete pouring 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.
The distance from the frame beam of the house to the ground must be at least 50 centimeters.
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:

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.
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.

How much will the foundation of a 10 by 10 house cost with your own hands?
Raise the house on jacks and replace the foundation with your own hands

The durability of the entire house will depend. But first, it is important to carry out a number of calculations, as well as analyze the soil. Before laying the foundation, it is necessary to know the depth of soil freezing and its characteristics. In addition, to build a strip foundation, you will need to calculate the settlement, but it is necessary to determine the expected strength when the house has several floors and a rather complex structure. If all calculations are performed correctly, it will last for several decades. A preliminary soil analysis will allow you to understand which foundation is best for a house made of timber. This will be discussed below.

Choosing a foundation type

For a house made of timber you can choose:

monolithic;
shallow;
tape;
pile;
pile-screw;
columnar foundation.

The latter type, like the pile foundation, is not used as often, because the technology involves the use of machinery. If the building has little weight, then you should resort to the construction of a strip foundation. It is suitable for one-story buildings, because it is practical and can be used for soils that are characterized by low water levels and low levels of freezing.

The construction of such a base can be done manually or using a construction concrete mixer. When choosing which foundation is best for a house made of timber, you can also consider a monolithic foundation, the dimensions of which will be slightly larger compared to the house itself. This design is the most expensive and is suitable for soil with a moving top layer. Quite often, slab foundations become part of heaving soil. If you decide to build a one-story house, then the slab can act as the floor, as well as the floor of the basement. However, this type of foundation is almost never used for the construction of lightweight timber buildings.

Alternative solutions

If none of the above options suits you, you can consider a rubble base, which is constructed using stone and cement. The work will be quite labor-intensive, but the foundation will have high strength indicators. Such a structure should not be left unloaded in winter, because it can be deformed, and subsequent construction will be complicated. It is best if the manipulations of building a house are a continuous process. This is why planning is so important in this matter.

Choosing a foundation for a house with a basement

Quite often, owners of building plots take a long time to decide which foundation is best for a house made of timber. If the building is two-story or one-story, but with a basement, then you should take into account how close the groundwater is. A strip base is better suited for this, because it will make it easier to fill gaps for doors and arches.

When choosing a columnar foundation, you will need to install screw pipes or piles, which are covered on top with concrete or reinforced concrete slabs. Sometimes beam grillages are used in this design. This base acts as one of the most versatile and low-shrinking.

For a pile foundation, at the first stage it is necessary to mark it by digging a hole in each corner. A sand cushion is poured onto their bottom, reinforcement is laid, and the space is filled with M-200 concrete. If you still haven’t decided which foundation is best for a house made of timber, then you should also consider the technology of constructing a screw and columnar foundation. In the first case, it will be necessary to purchase screw piles, which are screwed into the corners using special equipment. However, you can enlist the help of several people and handle it yourself. The distance between the supports will be 1.5 m.

When arranging a columnar foundation, it is necessary to dig holes in the corners, the depth of which will be 0.5 m. A sand cushion is poured into their bottom, and then pillars made of brick or any other suitable material are laid.

Strip foundation laying technology

Such a structure can be filled with concrete mortar using crushed stone, sand and cement in a ratio of 2:2:1. Instead of sand, you can use ASG. At the first stage, formwork from boards is installed, then sand is laid, metal strapping is laid and concrete is poured.

You can use metal waste and old pipes that fit the shape as fittings. After pouring, the concrete is left until it matures, and then the formwork can be removed.

At the first stage of the work, it is necessary to mark the area by laying geotextiles to create a barrier that will prevent the mixing of clay and sand. Next, a sand cushion is installed, which is prepared from a mixture of sand and crushed stone. This layer can be compacted using a vibrating plate or manually. Compaction is carried out in separate layers 10 cm thick.

If you have decided what kind of foundation is needed for a house made of timber, and have chosen a slab foundation, then at the next stage you can begin laying communications. To do this, concrete preparation is carried out, consisting of a cement-based screed of grade M-100. The thickness of this layer will be 10 cm. Waterproofing materials can be laid on a concrete slab formed in this way by connecting the seams with a blowtorch or propane torch. The size of the waterproofing should be larger than the future foundation, this will allow the edges to be turned up.

Insulation made of extruded polystyrene foam is laid on top of the layer. This stage is not mandatory, but can provide a warm floor and allows you to save on heating your home. When thinking about which foundation is best to choose for a house made of timber, you may prefer a slab foundation, which is most often installed on heaving soils. At the next stage, the reinforcement should be laid, which will consist of two meshes of rods with a diameter of 12 to 16 mm. The first mesh is laid in the lower part, and it is necessary to distance it from the polystyrene foam layer by 5 cm. The second mesh should be located 5 cm below the upper part of the base. Formwork must be installed around the perimeter of the slab so that it becomes possible to pour concrete and compact it using vibrators or manually.

We should not forget about the need to smooth the top layer of concrete. Next, the slab is covered with film and left for 4 weeks, during the first of which it is necessary to moisten the surface. As soon as the concrete hardens, the waterproofing on the sides must be turned up and soldered to the ends of the structure. After the foundation has gained strength, you can begin further work.

Rubble foundation laying technology

If you also need to decide what is the best foundation for a house made of timber, then you can consider a rubble foundation. It is laid in a trench limited by formwork. At the bottom you need to fill a 30-cm cushion of concrete, pre-reinforced with rods. At the final stage, a rubble base is installed on the pillow.

The stones should be wetted before use to ensure better adhesion to the concrete. The stone should be laid with a gap of 3 to 5 cm; they should not be located close to each other. All developers seriously think about which foundation is best suited for a house made of timber. One of the most popular today is a rubble base, which is constructed according to a certain algorithm.

It says that the long side of the stone should alternate with the short one. To install the elements, a sledgehammer and a hammer in the form of a cam are used. You can replace these tools with others that are similar. The optimal thickness of the masonry varies from 50 to 70 cm. In this case, you can also use clay, which is added to the solution for plasticity, but you should not be zealous in this matter.

Features of stone laying

When choosing the best foundation for a house made of timber, you need to pay special attention to the rubble technology, which allows you to create a base that is attractive in appearance. If you mount elements under the blade, then a row of butts is first laid dry on the prepared base. The stones are compacted and the voids are filled with small stones. Next, you can proceed to filling the space with liquid solution. The next step will be laying the spoon row, which involves placing the stones with the long side.

Conclusion

If you want to build a foundation for a house from timber, which one to choose is important to determine correctly. The main varieties were presented above, but whatever the choice, technology should be followed. In all cases it states that concrete matures in 30 days. During this time it must be protected from drying out and precipitation.

One of the most important factors in the durability of the entire structure will be the waterproofing of the foundation. To do this, its surface is coated with bitumen. After you have decided what kind of foundation is needed for a house made of timber, you should study the technology in more detail; the information presented above will help you with this.

Houses made of timber remain popular, despite the fact that a large number of other materials for building walls have appeared. There are several reasons for this. These include environmental friendliness of the building, fairly low thermal conductivity of the material, attractive appearance and availability of wood. To avoid unexpected problems during the operation of the building, it is important to choose the right foundation for a house made of timber.

Characteristics are considered only in relation to the foundation. From this point of view, wooden beams are the best option for building walls. This also includes log houses. There are several reasons for this conclusion:

Resistance to slight deformations in the soil. Unlike a brick or aerated concrete building, a timber house is not afraid of minor shrinkage of the supports. This is due to the fact that the walls are assembled not from small, loosely connected elements, but from long parts. In addition, the deformation modulus of wood allows it to bend slightly following the base. When shrinkage occurs or the soil rises due to frost heaving, timber walls do not crack (provided that the displacements are small). If the foundation deformations are large enough, the building will tilt.
Light weight. The smaller the mass of the walls, the less load falls on the base. This allows you to save money and reduce labor costs during the construction of foundations. To compare different materials, you can see the table.

Material	Density, kg/m2	Optimal thickness according to thermal performance indicators (on average) taking into account the coefficient m p = 0.63 according to clause 5.2 of the SP “Thermal protection of buildings”	Weight of a linear meter of a wall with a height of 4.5 m (for a two-story house, the second floor is an attic with a height of external walls of 1.5 m)
Ceramic brick	1800	640 mm	5184 kg
Foam concrete (load-bearing with sufficient strength)	900	500 mm	2025 kg
Wood (pine, spruce)	520	300 mm	702 kg

The table shows how much the load on the foundation is reduced when using timber as a building material for the walls of a house. In addition to the values in the table, it is necessary to take into account a lot of other house structures, payload and snow.

What type of foundation to choose

When building a house from timber (as well as from other materials), it is important to determine what the foundation should be to ensure reliability and safety of operation. The choice depends on the following factors:

soil strength characteristics;

location of groundwater level (GWL);

the need to arrange a basement, plinth, technical underground;

the depth of soil freezing and its tendency to heave.

Due to the small mass of the house and resistance to deformation, we can say that it is permissible to use almost any foundation for a log house. At the same time, unlike brick or foam concrete, there is no strong difference for a one-story or two-story building. The mass of the house structures is such that it allows the use of foundations with a relatively small load-bearing capacity even for a two-story building.

Timber house on a slope.

There are several options for foundation design for timber construction:

tape ( , );
(Same);
(Same);
pile ( and ).

To make it easier to choose between them and determine which one is better to use for certain conditions, it is recommended that you familiarize yourself with the table below.

Construction Features	What is the best type of foundation to choose?	Regulatory documents according to which the calculation and construction of supports for a house made of timber should be carried out
Basement required	Recessed strip or recessed slab	JV “Design and installation of foundations and foundations of buildings and structures”; JV "Concrete and reinforced concrete structures"; JV "Pile foundations".
Construction on clayey soil prone to frost heaving (clays, loams, sandy loams, as well as fine and silty sands) with the groundwater system located deep underground	Strip and column foundations laid below the freezing depth of the soil, shallow and non-buried types of foundations (strip, pillars, slab) with sufficient insulation, pile supports
Construction on clay soil with the groundwater level located quite close to the ground, but at a distance of more than 1.5 meters from the surface	Shallow strip, pillars or slab (depth is within 0.5-0.7 m) with insulation, pile supports, deep foundations (strip, column, slab) when carrying out the necessary measures for waterproofing and drainage
Construction on clay soil with the groundwater level located at a distance of 0.5 to 1.5 meters from the surface	Non-buried bases In terms of bearing capacity on the presented soils, such foundations are suitable only for small one-story buildings. It is better not to use columnar ones (low load-bearing capacity). You can also use screw piles or bored piles to ensure soil drainage while the structure is being poured
Construction on a coarse foundation or sand of medium or coarse fraction with the groundwater level located at a distance of 1.5 m and below from the surface	These soils are non-heaving and have sufficiently high strength; almost any support can be used. An economical option for construction from timber would be a shallow strip or columnar foundation. If a basement is necessary, take into account the location of the water mains, which must be at least 50 cm from the base of the foundation (if the condition is not met, drainage, drainage and waterproofing of the structure are required)
Also at a groundwater level of 0.5 m and below	It is worth choosing non-buried types of foundations. Use with caution, only after calculating the load-bearing capacity. May not be suitable for a two-story house.
The location of the groundwater level is closer than 50 cm to the surface of the earth for any type of soil	In this case, the best option for construction from timber would be a pile-screw foundation, which shows good results when working on swampy foundations and soils with a high degree of water saturation. The use of strip, slab or columnar is almost impossible. This is due to the fact that measures to remove moisture from the site with such a volume may not be effective
Construction on a slope	Determined depending on the steepness of the area. The simplest option in this case is screw piles. You can also use a slab, tape or pillars, but you will have to develop the soil so that the slope occurs with ledges or make a tie-in (for a slab). With a slope steepness of less than 8%, a strip foundation can be made as for a flat area

Important! In most cases, you will have to take into account several of the features indicated in the table and make a choice in favor of the most suitable option.

It is clear from the table that before making a choice, you need to determine the characteristics of the foundation for the building. You can do this yourself by digging holes or by hand drilling.

To build a reliable house from timber and correctly determine what kind of foundation is required, it is important to take into account many points. But still, construction from this type of material gives more options than from more massive brick or concrete.

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Choice of foundation. Its varieties

Shallow strip foundation. Experts recommend using it specifically for the construction of a house made of timber. This is due to its practicality and ease of manufacture. Pouring such a foundation occurs using a mixer, or with your own hands. You need to use only high-quality concrete grades, such as M300 and higher. When making your own foundation, it is important to properly prepare the mixture. The proportions of cement, crushed stone and sand should be 1:2:2.
Monolithic slab. Such a foundation is located under the area of the entire house in the form of a reinforced concrete slab or a structure consisting of reinforced concrete beams. It is used most often on heterogeneous soils that can move. Its installation will lead to high costs. It can be used as a foundation for a small log house, where a reinforced concrete slab is used as a subfloor.
Pile foundation. This structure consists of several piles, which are covered on top with a reinforced concrete slab. This type of base is universal and economical, but is much less common than all others. This is due to the fact that for its construction you need to use special equipment. These piles will be indispensable in areas where the upper part of the soil is mobile. You can see what this foundation looks like in the video.
Other types. In addition to the above options, today you can find both rubble and brick foundations. A rubble foundation is constructed from rubble stone and cement mortar. This construction is labor-intensive and complex, but the result will be a durable and strong foundation. A concrete foundation can also be found as a structure for a log house. In another way it is called “poured”, and it contains concrete in its pure form.

Marking for the foundation on the site

Scheme of correct marking of the foundation on the site

Proper digging of a foundation pit

Sand cushion for the foundation

Installation of formwork. Choosing edged boards

Foundation reinforcement and ventilation

Preparation and pouring of the solution

In order for the strip foundation for a house made of 8x8 timber to be of the highest quality, you need to follow the following recommendations:

Foundation cost

To make a strip foundation with your own hands, you need to be prepared for many costs. It is impossible to determine its cost with accuracy, since it will depend on several factors:

Amounts of materials used. These are sand, crushed stone, cement, wood, edged boards, etc.;
From the number of devices. These are nails, self-tapping screws, screws, etc.;
Construction of a house from profiled timber and other types and its layout;
From the cost and time of renting special equipment or hiring additional labor;
On the condition of the land on which the strip foundation will be made.

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. During its construction, a reduction in building materials and the volume of work itself is achieved. 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. The characteristic features of this option are 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, a sand cushion is used. 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, you shouldn’t calculate this parameter right away; sand will always come in handy during construction work.

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.

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