The foundation is the basis and reliable support of each building, both a solidly built multi-story building and a lightweight frame house. The durability and stability of the house, its long service life will depend on the features of the foundation base.
It is the foundation that bears the main load of the future building, so the choice of the foundation must be approached responsibly and at the highest professional level. The specialists of the company DorHan give several tips on choosing a foundation for the now widespread frame construction of houses.
Rules for choosing a foundation for a frame house
In modern construction, various types of foundations are used, each of which has its own design features and is intended for specific conditions of use.
When choosing a foundation, the following points are taken into account:
- geological features of the soil: density, type of soil, groundwater level;
- the depth to which the soil freezes;
- nuances of the soil itself: heaving, stratification;
- climatic nuances of the region where construction is planned.
When constructing buildings using frame technology, several types of foundations are used. For frame buildings, the foundation is selected taking into account the lightweight structure, its expected dimensions and soil characteristics. Let’s consider them in more detail.
Strip foundation
The most common type of foundation for a frame house. It is actively used in civil engineering and is considered one of the most reliable and strong foundations with a long service life. There are two types: monolithic and prefabricated. For frame houses, a shallow strip type is mainly used, which is a reinforced concrete strip. It is laid along the entire perimeter of the building being erected and all load-bearing walls.
When considering the materials used for strip foundations, the following can be distinguished:
1. Brick. Can bear increased loads, but has a reduced bearing capacity, which makes it less durable compared to a reinforced concrete base.
2. Reinforced concrete. The cheapest in cost, designed for high loads, but expensive in terms of arrangement. It requires the use of special equipment, which does not have the best effect on the pace of construction.
3. Rubble concrete. This is a type of concrete foundation. The main feature is that the formwork is filled not with classic reinforcing elements, but with stones, brick fragments, gravel. This gives the rubble concrete foundation special reliability and strength.
When using a strip foundation in frame construction, the owner can easily arrange a garage for a car or a basement, a subfloor under the house. But keep in mind that this type of foundation requires the use of special equipment due to the increased volume of excavation work. Despite this, strip foundations are very popular due to their low cost, high strength and simplified technology.
Columnar foundation
Another option that is in great demand in frame construction. It shows particularly high efficiency on stable soils that are not prone to swelling. A columnar foundation is ideal for areas with deep soil freezing. When installing it, brick or concrete pillars are installed in high-load sectors and at the corners of the future building. The space between them is filled with crushed stone or sand. The supports are connected to each other with reinforced concrete cross beams.
This type of foundation is ideal for building outbuildings, baths, gazebos, verandas, and sheds. The popularity of this type of foundation is explained by a number of advantages:
·it is economical and easy to implement;
· does not require preliminary leveling of the site;
· quick to install and durable;
· ideal for construction in areas with sharp differences in height;
·does not require additional involvement of special equipment.
But keep in mind that a columnar foundation is not suitable for building very heavy walls. When using it, you will not be able to arrange a basement in a frame house. It is also not suitable for lands with unstable and mobile soil.
The depth at which the support pillars are laid also becomes variable:
· non-buried: installed on the soil surface and does not require additional excavation work;
·shallow: installed at a depth of up to 70 cm from the soil surface;
· recessed: laid below the freezing level of the ground.
Asbestos pipes, brick, wood and stone are used as materials for its construction. Their choice will depend on the number of storeys of the proposed house.
Monolithic foundation
It is a reinforced concrete monolithic slab. It is located over the entire area of the proposed house and can be used on all types of soil. A monolithic foundation is considered one of the highest quality solutions, but requires larger financial investments compared to other analogues.
The advantages of this type of foundation for frame houses include the following points:
· the pressure of the soil on the foundation is minimized, which prevents the formation of cracks;
· ideal for use on floating and unstable soils;
· provides an optimal level of stability and strength to the building;
· evenly distributes the load-bearing load over the entire area;
· quick to install and can be used in the construction of frame houses of any number of storeys and configurations.
But keep in mind that the concrete from which the foundation pad is made has high thermal conductivity. This leads to the appearance of “cold bridges”. Therefore, when choosing a monolithic foundation for your home, provide additional thermal insulation.
Pile foundation
The technology of such a foundation is based on the use of steel, especially strong piles in the soil to a depth below the freezing point. When constructing a frame house, piles are arranged in two ways:
1. They are screwed into the soil using screw blades or are driven tightly into the ground. To ensure the required strength, a beam (strapping) is additionally used. It is placed on the pile heads.
2. Installed using a concrete grillage: first, wells are drilled and filled with concrete. Then support columns are installed in them. The grillage is a low concrete strip, it secures the tops of the support columns and rises slightly above the ground level.
Regardless of the type of pile foundation, the support pillars are mounted at a distance of up to 2 m from each other. This ensures the stability of the floor, the absence of its sagging during future use. Knowing the distance and footage of the house, it is easy to calculate the amount of material required.
The advantages of a pile foundation include the following points:
· construction speed: all foundation work can be completed within 24 hours;
· pile foundation is ideal for any type of soil;
· it is resistant to soil freezing and the destructive effects of groundwater;
· it can be arranged at any time of the year, regardless of climatic and weather conditions;
· ideal for building a frame house on a sloping area.
But keep in mind when using a pile foundation that it is mandatory to close the base, otherwise the heat will quickly escape through the base of the floor. You will have to refuse to arrange a basement or cellar – such a foundation does not imply the arrangement of underground rooms. The cost of a pile foundation becomes higher in comparison with a monolithic or strip foundation.
Slab foundation
A slab foundation is a monolithic base, the basis of which is concrete with reinforcement (grade M250-M300). This type of foundation is extremely durable and reliable. But you should pay attention to the monolithic nature of such structures. In severe frost, the resulting heaving load acts on the foundation as a single structure, which can lead to its movement or tilt.
Therefore, when using such a foundation, frame structures must be 100% insulated from frost heaving, which often causes the destruction of buildings. But due to its massiveness, a slab foundation in frame construction can withstand serious loads.
Other advantages of a slab foundation include the following:
· when using it, it is possible to equip basements, full-fledged and large-sized ground floors;
· the technology for constructing a slab foundation is extremely simple, so you can do it yourself, even without professional knowledge and extensive experience;
· when using a slab foundation for frame construction, the durability and reliability of the foundation is significantly increased;
· due to the shallow depth at which the supporting structures lie, this type of foundation requires a minimum amount of excavation work.
But when choosing a slab foundation for a frame house, keep in mind that its cost is quite high due to the need to purchase a large amount of reinforcement and concrete. Builders call the base plates for a slab foundation “floating”, because the reinforced concrete structure is placed at a fairly shallow depth (up to 40-50 cm), and during frost heaving it can move, following the ground movements.
The installed foundation slab simultaneously serves as the base for the frame house and the floor of the first floor of the house. It evenly and stably distributes the load from the structure onto the ground, contributing to the reliability and stability of the building. During construction, special attention is paid to the formation of specialized drainage from crushed stone or coarse gravel under the slab. The drainage layer stops the destruction of the base during severe freezing of the ground. The thickness of the entire foundation base can be 15-20 cm.
If you have doubts and cannot correctly determine the choice of a suitable foundation for frame construction, contact the specialists of our company for help. We will be happy to advise you on which type of foundation to choose, taking into account all the features of your climate, the nuances of the soil, the land plot and the complexity of the planned project.