Strip foundation for a wooden house

Strip foundation structures

Strip foundations occupy a significant segment of the market for individual housing construction, and differ in the type of device and depth of installation. This is not just a classification for the sake of additional nomenclature - the principle of operation of the structure and the technological processes associated with the construction of the foundation depend on the depth of the foundation. Determining the geometric dimensions of the strip foundation for a log house is very simple, for this you need to follow a certain method.

Shallow tape

Shallow tape supports are characterized by low strength. But such a foundation for a log house is an excellent option for an economical and reliable solution. Only an unburied tape or pile foundations can be cheaper than a shallow one, but they are not always suitable for the type of soil and strength. The average depth of a shallow tape is 50-60 centimeters, which is almost always in the zone of soil freezing.

Log house on a strip base

The standard dimensions of foundation blocks are in the range from 300 to 1200 mm and are graduated in 300 mm increments - this parameter will determine the width of the foundation slab. Whatever the depth of freezing, the foundation for a shallow blockhouse will be located in the zone of freezing of soils, which obliges the developer to arrange drainage systems in order to divert groundwater - otherwise neither a high basement (from 400 to 1500 mm) nor strong concrete will save the structure from destruction under the influence of frost heaving.

Deep-laid tape

It is necessary to use a deeply buried strip foundation for a log house with dimensions of 6x6 m only if a two-story wooden house is being built or the groundwater level is in the freezing zone, which immediately makes the soil highly weathered. The depth of the foundation strip foundation can be in the range from 0.8 meters almost to infinity. Reasonable depth of the foundation base is 2.5-3 meters, taking into account the arrangement of the basement floor.

Erection of a log house

The width of the tape will depend on the width of the wall structures. The minimum cross-sectional dimensions are in the range of 300-400 millimeters, depending on whether a prefabricated or monolithic structure is used.

It should be understood that prefabricated strip supports consist of two types of blocks - a foundation slab (a trapezoid with a top from 300 to 600 mm) and a foundation block, the width of which corresponds to the upper edge of the foundation slab.

The width of the base of the slab is always greater than the width of the block, so a trench of the appropriate size should be arranged. After the installation of the support structure and the side waterproofing device, the soil is backfilled with compaction.

Shallow tape

The advantage of shallow foundations is that they stand on the surface layer of the soil, which excludes the effect of frost heaving on the side walls of the foundation slab. Preparing the site for the installation of a non-buried tape consists in arranging a solid foundation.

After that, the formwork can be installed. The height of the above-ground part of the foundation is determined taking into account the mass of the wooden house. The bearing capacity of a well-prepared soil allows building a foundation for a log house with a height of at least 30 centimeters. Thus, we can assume that the minimum vertical dimension of an unburied foundation, taking into account the prepared cushion, is 0.8 meters.

The dimensions in the plan should correspond to the dimensions of the house in the axes, while it is rational to arrange the foundation, taking into account the presence of 10-centimeter basement protrusions in and out of the walls.With an average thickness of wooden walls of 400 mm, the width of the foundation will be 420 mm - this size should be divided in half and the resulting value should be set aside on both sides of the center lines of the walls.

We recommend watching a video on how to make an unburied tape base yourself.

Types and types of foundations for wooden buildings

Types and types of foundations

At the moment, the following types of foundations for a wooden house are distinguished:

tape;
columnar;
pile;
slab.

Strip foundation

The tape design is the most widely used today. It can be divided into the following groups:

Recessed.
Shallow.
Shallow.

The construction of a buried strip foundation is relevant if the depth of freezing of the soil is significant, the groundwater is very close to the surface, or the structure will have a basement, basement or garage.

A shallow design is best suited specifically for wooden houses. This is due to the fact that the weight of such buildings is much less than that of brick. The height for a wooden house above the ground ranges from thirty to fifty centimeters. For this reason, it is used in situations where you want to save on the foundation without losing its quality.

Shallow foundations are suitable for small wooden structures or those that are only needed temporarily.

The process of erecting a strip foundation can be represented in the form of the following stages:

Digging a pit. The value of the depth of the foundation of a wooden house must necessarily be greater than the value of the depth of freezing of the soil (by about twenty centimeters). As for the width of the pit, this value is equal to the width of the foundation, to which is added half a meter for formwork and ease of work.
Making a cushion of sand and cement. A mixture of sand and cement is placed at the bottom of the pit. The thickness of the layer should be at least fifteen centimeters, and preferably twenty centimeters. The mixture must be compacted: for this, it is first poured with plain water, and then compacted. The purpose of the sand-cement pad is to reduce the load on the structure.
Formwork creation. In order for the surface of the structure to be as flat as possible, the formwork must be knocked down from the inside, and the nails must be driven in from the outside. Following this advice will also make it easier to dismantle the formwork.
Installation of spacers.
Reinforcement laying. Under no circumstances can the elements be connected to each other by welding: only wire can be used.
Pipe laying. They are essential for communication.
Pouring concrete.

Column foundation

This design is suitable for soil with a serious freezing depth, which at the same time regularly swells. Also this foundation can be applied on uneven terrain.

The device of a columnar structure involves the use of blocks of concrete, bricks and asbestos pipes. Therefore, it is not suitable for buildings with a basement or basement.

The technology for erecting a columnar foundation is as follows:

The place where the pillars will be installed is determined. Despite the fact that the distance between them is determined by the size of the house, it should not be less than one and a half meters.
Installation of pillars. They go deep into the ground by about 50 - 70 cm. At the same time, a sand-cement pad should be made under each of them.

Pile foundation

Such houses are built in areas with uneven terrain or in the event that the soil is unstable. It is also suitable for situations where the water table is high or changes frequently.

The pile structure is arranged in almost the same way as the columnar structure. The only difference is that the elements in this case do not just go deep into the ground, but are screwed in.This is possible due to the fact that there is a drill at the end of each pile.

Slab foundation

The slab foundation is indispensable for moving soil. The construction of this foundation involves the manufacture of a monolithic concrete slab with reinforcement. Its area is exactly the same as the area of the house. One of the advantages of such a slab is that it is mobile, so that the house is not damaged when the ground moves.

The slab foundation is erected as follows:

First, the foundation pit is pulled out. Since it will be large, most likely it will not be possible to do without the involvement of special equipment.
Making a cushion of cement and sand.
Reinforcement laying.
Pouring with concrete.

The device of a slab foundation is not an easy task. The main difficulty in this work is to achieve uniform drying of the concrete over the entire surface of the slab. Therefore, if a tiled foundation is the only possible option, then it is best to seek help from a specialist.

Preparation of a working project for a wooden bath

The erection of a log house for a bath is a laborious and responsible process that is carried out in stages. The initial stage is the preparation of the bath project.

A typical project includes:

choosing a suitable building site;
the layout of the number of storeys and internal premises of the bath;
layout of the location of window and door openings;
selection of heating, ventilation equipment and lighting devices;
selection of building and finishing materials;
development of room design;
calculation of the cost of construction.

Finished projects are freely available, but to get an individual sketch, you should contact the design office.

Foundation device from logs

The procedure for installing a columnar foundation made of logs:

markup. Determine corner points. The first supports are placed in the corners, then a cord is pulled between them. The next pillars are then aligned on this berth under the horizon.
dig holes for the supports, using a shovel or a garden drill of a suitable diameter. This diameter should be one and a half times larger than the diameter of the pillar. At the bottom of the pits, a compacted cushion of coarse sand 200 mm thick is made. The sand is rammed in layers of 100 mm, wetting with water.
the posts are wrapped in roll-up waterproofing material glued with bitumen or mastic. When the pillars are loaded with the weight of the house, this treatment will give an additional effect, the horizontal movement of soil layers will not affect the pillars due to low friction
the bottom of the pits is covered with fine gravel 10 cm thick, then the pillars are installed with the butt down, adjusting their verticality with a level. Supports are placed along the axis of the walls, the top of the logs is cut down to the horizontal mark. Installation of pillars of supports on "chairs" in the form of a cross, fixed to the lower end of the log, will significantly increase the resistance of the pillar to wear.

backfilling. Fall asleep with coarse sand or gravel fraction 5-10. The backfill is done with careful compaction in layers, the layer thickness is not more than 20 cm. The backfill creates a filtering layer. In this case, the vertical position of the pillars must not be disturbed.
in conclusion, all the supports are once again aligned under the horizon along the mooring cord. Surplus logs are cut down. The ends are coated with bitumen or mastic for waterproofing.
then fastening is made at the ends in the form of thorns for the first row of beams or logs of the walls. This completes the work on the arrangement of the underground part, then the piping is performed.

A columnar log foundation, subject to high-quality antiseptic treatment, will last for more than a dozen years.

The foundation made of logs has drawbacks, but despite this, they are widely used in private construction, because they have passed the test of time, and also allow you to build quickly, inexpensively and with your own hands.

Laying other types of foundations

Having considered the most popular and often used foundations in the construction of wooden houses, we will talk about several more types of foundations that you can build with your own hands.

Pile-screw base of the house

The easiest to install, as well as reliable and economical are considered pile-screw bases for buildings made of logs. If in your work you use high-quality material that is coated with an anti-corrosion agent, then the result is a durable structure.

The individual element looks like a rod with a surface in the form of a screw, and a sharp tip is located at the bottom. It is because of their structure that it is quite easy to screw these piles into the soil, to a solid layer of soil. First, all the parts are installed, and then the top must be cut so that all the piles are located at the same level and filled with concrete.

Some use a combination of several types of foundation. For example, the main building is located on a slab base, and an additional one, such as a veranda, an extension - on a pile-screw or columnar. But, according to experts, this cannot be done, since this structure is not only unreliable, but also dangerous. This is due to the fact that a separately attached room is usually connected by one roof. And when the main structure or an additional one shrinks, as a result of the influence of temperature changes or groundwater, the roof may be crooked, which will require additional costs from you for its restoration. Moreover, in some cases, even violations of the wall integrity are possible.

However, not all foundation combinations are bad. There is, for example, a strip-pile view of the base, the instructions for its construction are as follows:

Mark out the site and remove the upper, fertile ball of soil.

A moat is being dug along the entire width of the future walls, moving along the entire perimeter. Its depth should be at least 30 centimeters.

After a step of two meters, it is necessary to drill wells with a diameter of 18 centimeters and a depth of about one and a half meters.
A sand layer is laid on the bottom.
A frame is made of reinforcement and lowered into each well.
Pits with laid frames are filled with concrete mortar, which must be properly tamped.
For a part of the strip-type foundation, install a wooden formwork. It must necessarily rise half a meter above the ground.
A frame made of reinforcing metal for a strip base is welded and knitted with elements protruding from the wells.
Pour the foundation.
After the foundation has completely dried out, waterproofing is performed with roofing material folded several times and smearing it with mastic

It is very important to hold such an event before building a log house.

Well, now we figured out what technology for pouring the combined foundation.

Pile, pile-screw base

According to the principle of operation, the pile base is similar to the columnar base, only special elements designed for high loads are used as supports. The way the piles are driven into the ground depends on the type of element. The advantages include the possibility of building on a site with a large height difference, no need to carry out voluminous earthworks.

The advantages of pile foundations include the ability to install on difficult soils. For heavy capital structures, reinforced concrete piles are used, but the foundation for a house made of logs does not require serious financial costs for the piles themselves and the equipment for their installation, it is enough to use screw.

Screw piles are steel pipes with special blades at the lower end for easy submersion of the element into the ground. Due to a special coating, the metal is protected from corrosion.In order for the building to stand for a long time, piles with a wall thickness of at least 4 mm are chosen and the metal is additionally processed at the border of the soil and the atmosphere - this is the most vulnerable area.

The diameter of the piles is selected depending on the size of the base and the number of storeys of the building, as well as taking into account the characteristics of the soil, otherwise, when the screw element is immersed, there is a risk of deformation of the pipe. A deformed pile does not correctly perceive and transfer loads, which reduces the strength of the foundation foundation.

Screw piles are used on any type of soil (including loose), with the exception of marshy and rocky. The process of arranging the base includes:

marking the site for the installation of piles according to the project;
digging holes for piles;
screwing in piles using hand tools or a special mechanism;
control of the verticality of elements, cutting off protruding parts in such a way that a horizontal plane is formed;
welding of mounting plates or erection of a monolithic reinforced concrete grillage.

Screw piles are a good option for construction on slopes, on soft soils, in conditions of close water occurrence.

What concrete is needed for the foundation of a wooden house

Normative documents:

GOST B V.2.7-44-96 "Cement".
GOST B V.2.7-46-96 "Cements for general construction purposes".
GOST B.2.7-65-97 "Additives for concrete and mortar".
GOST B.2.7-69-98 “Additives for concrete. Determination methods ".

In short, when choosing a cement for concrete, you need to take into account the characteristics of the soil, the expected load, the type of foundation, the height of the groundwater. As for the cement grade, the M150 grade is suitable for wooden one-story houses.

However, professionals advise not to save on the brand and purchase cement with a brand not lower than M400. In this case, preference should be given to Portland cement with additives, which has the necessary properties

As for the cement grade, the M150 grade is suitable for wooden one-story houses. However, professionals advise not to save on the brand and purchase cement with a brand not lower than M400. In this case, preference should be given to Portland cement with additives, which has the necessary properties.

You can make concrete with your own hands based on M400 cement based on the data in the table, where C-cement, P - sand, U - crushed stone.

When building a wooden country house or summer cottage, special attention should be paid to waterproofing the foundation. To prevent cracking of the foundation, after pouring it is treated with various compounds (for example, penetron) or bitumen-based films

Waterproofing allows you to protect the foundation from water (ground, thawed, rain).

An additionally flooded blind area near the house will allow water to be diverted and preserve the foundation. The ebb on the foundation of a wooden house will also be an excellent protection against moisture. It is mounted in such a way that it protects the basement of the building.

Low tide on the foundation of a wooden house

Conclusion

We hope that the information and instructions given in the article will allow you to figure out what types of foundations are for a wooden house, how to make one or another foundation with your own hands, and what factors should be taken into account when choosing.

Types of foundations for the house

Columnar base - these are the most popular devices for bar buildings

Today, there are such types of bases for a wooden house, which have their own distinctive characteristics. So let's take a look at them:

Strip foundation - this type is characterized by a cross section equal to the shape and size of the entire structure. Most often used in the construction of heavy large buildings. Materials are used for work: bricks, concrete blocks and flagstones
Columnar base - these are the most popular devices for bar buildings. For construction work, a minimum amount of materials is required.Pits need to be made along the perimeter of the site every two meters.
The foundation for a slab-type wooden house. Such a device has gained popularity in classical construction projects. To complete the process, you need a large amount of concrete and reinforcing mesh. It is worth noting that a lot of physical strength is needed to complete the work.

Pros and cons of columnar type

The columnar type of the building base has a structure suitable for laying under light or wooden buildings

The columnar type of building base has a design suitable for laying under light or wooden structures that place little stress on the soil. It should be noted that the simplicity of such a device is not reflected in any way on the reliability of the supporting ability. Schematically, the view of the foundation resembles a system of pillars installed at the highest pressure points. The norm between the pillars of the columnar structure is 2 meters.

The posts are made from brick, concrete, stone and other materials. Insulation and waterproofing must be carried out together with the filling, that is, connecting the walls with the pillars. Installation work begins with the preparation of a pit 50 by 50 by 50 cm. Further, it is filled with rubble, which creates a pillow, and a pillar of blocks is installed. The columnar view of the base has the following advantages:

High level of reliability;
Durability;
Low installation costs;
The ability to erect buildings in almost any conditions;
There is no need for additional processes such as waterproofing and insulation;
Low level of labor intensity of the construction process;
It is possible to build a columnar mechanism on freezing soil

With all these advantages, let's find out what is the disadvantage of this type of building? And there are several of them, so:

Lack of the possibility of building a basement;
Not suitable for installation on mobile soils;
Withstands the load of light buildings only.

Bored pile foundation: pros and cons

The base of the bored asbestos cement foundation is a type of columnar type, where pipes serve as pillars

The base of the bored asbestos cement foundation is a type of columnar type, where the pipes function as pillars. Structurally, they consist of piles and a grillage connecting them to each other. The load-bearing components of the bored foundation are placed at the pressure points of the building. It is worth considering that the structure can be influenced by horizontal forces, then the installation of piles can be installed at an angle. The advantages of this type: