A foam block is a material that has earned the trust of many builders. It has the shape of a parallelepiped with sides of 30 and 40 cm. Foam blocks are made of foamed concrete. The composition also includes cement, sand and water. The mass of material due to the porous structure is very small, so the foundation for houses made of foam blocks may not be very massive. The material is characterized by a gray color, does not sink when immersed in water (due to its porous structure). The characteristics are almost the same as those of aerated concrete, the difference in materials is only in cost. In this short review, we will look at how to build a foundation for a foam block house.
Positive properties of foam blocks
Foam blocks have a low cost when compared with similar building materials. But the buildings from them have rather high performance, in many ways they even surpass the buildings made of wood or brick.
Also, do not forget about the following advantages of foam blocks:
- No harmful impurities are used in the production of the material, so the blocks are environmentally friendly and cannot harm your he alth. If you focus on sanitary standards, you can see that it is allowed to build children's institutions from foam blocks - there are no barriers.
- One of the pluses is the excellent level of sound insulation. Walls made of foam blocks do not let in sounds. Therefore, there is no need to make additional soundproofing.
- The foam blocks can be cut into any shape - they are very easy to process.
- Due to the porous structure, high-quality air exchange between the street and the house is ensured. And the soundproofing is top notch. It should be noted that the walls do not let heat out.
A little more about the features of the material
When making a foundation for a house from foam blocks, dampness will not affect the material. This is another good quality of the material, because you do not need to install additional structures to get rid of moisture. There are also such features of the material:
- Laying foam blocks is much faster and easier than bricks.
- The maximum joint size is 3 mm, so when laying it is allowed to use both cement mortar and special adhesives.
- When finishing, you do not need to lay a large amount of plaster, because the surface of the walls is made of foam blocksalmost perfectly flat.
- When the material is heated, neither expansion nor deformation occurs.
But you should pay attention to the disadvantage, and a significant one - not very high strength. Therefore, when building a foundation from foam blocks for a house, this moment must be taken into account.
Varieties of foundations for buildings from blocks
Now let's talk about how to choose the right type of foundation. In total, there are four types of bases that are used in the construction of foam block houses:
- Columnar - there is reinforced concrete in the structure. Pillars are made of square or round section. It is allowed to use a beam or grillage. There is also a belt made of reinforcement rods.
- Belt type foundation - usually a shallow or recessed structure.
- Pile foundations - usually in this case, hanging or screw piles, reinforced concrete grillages, pile-racks are used. The difference between this type of foundation is that there are reinforcing pile elements in the structure. In general, the design is very similar to a columnar or tape. Piles are the ideal solution for unstable foundations that require additional support.
- Monolithic design - not much different from similar designs. It is worth noting that the mass of the foam block is quite small, so there is no need to make a base of great thickness.
According to what parameters to choose a foundation
To choose the optimal foundation design, it is necessary to take into account allfeatures of the site on which the construction is carried out. The main thing in the foundation is that it must be strong and reliable, otherwise it will not be able to withstand the load of the structure.
But when calculating the base, you will have to not only focus on maximum strength, but also reduce construction costs.
Soil features
Be sure to take into account all the features of the soil at the place where the construction is carried out. It is recommended to carry out geological surveys in advance, which will help determine the quality of the soil. To do this, you can contact the experts. But if this is not possible, you can do everything yourself. To do this, with the help of a drill, it is necessary to make at least two wells with a depth of 2-2.5 m. From these wells, it will be necessary to take the earth for a sample in order to determine the main components. Three groups of soils can be distinguished:
- Heaving - a lot of loam, clay, sandy loam.
- Slightly sandy - may contain fine grains of sand or dust.
- Non-rocky - a high content of gravel sand with large or medium grains of sand.
Soil type selection
After analyzing the soil, you can determine the most suitable type of foundation. For example, for heaving soils, tape is the most inappropriate type. It is best to use a pile foundation. In the event that there is non-rocky soil at a depth of more than 2 meters, and freezing is much closer to the surface of the earth, it makes sense to use columnar or pile structures.
Be sure to calculate in such a way that the distance between adjacent pillars is sufficient to withstand the total mass of the building. It is recommended that the freezing depth be determined based on observations over several years. If we take the average, then this figure is 0.5-2 m.
Ground waters and deadlines
The level at which groundwater is located must be taken into account when building a foundation. If they are too high, then the possibility of using a strip base is automatically excluded. If you want to build a tape, then you definitely need to make drainage - this will prevent water from entering the foundation. True, the cost of construction will increase several times. The best option is a monolithic slab. Cheap and easy - these are the main advantages. But if you want to make a basement under the house, you will have to build drainage and a tape base.
Speed and price
And the last thing to consider is the cost of the work and the timing of their implementation. To build a house as quickly as possible, you need to put aside all complex structures. In terms of speed, pile and columnar are far ahead of all other types. In addition, they will require a small (relatively) investment of funds and effort.
But the most expensive and labor-intensive are the tape and monolithic look. And what is the best foundation for a foam block house - we will now try to find out. After all, it all dependswhat type of soil is on the site, as well as on your financial capabilities.
Production of the strip foundation
The strip base is ideal for soil that consists of clay. The depth of laying is calculated based on the freezing data. The width of the pit must be made such that it is larger than that of the block, by about 10 cm. More is better, but not less. The plinth should have a height of about 40 cm, the upper part must be reinforced with reinforcement bars. A rod with a thickness of 10-16 mm is used.
Construction procedure:
- First the pillow is laid. It is made from sand or a mixture of it with gravel. But first, of course, a trench is dug. Then a layer of sand 15 cm is poured, gravel - 15-20 cm.
- Now you can pour cement mortar - the thickness is not more than 10 cm. This is the so-called footing. After that, the layer should harden within a week. But you can't let the concrete dry completely.
- After the half-drying of the layer, it is necessary to make reinforcement. Reinforcement bars must be connected with wire. It cannot be fixed by welding, because the metal will be more susceptible to corrosion. It is recommended to use fittings with anti-corrosion coating.
- Install the formwork. It can be made from slate, wood, plywood, metal. Concrete is being poured inside.
- The mortar is made from three parts of sand, five gravel and one cement. Add water gradually so that the solution is not very liquid, but not too thick. If construction is taking placein the cold season, you need to add additives.
- Pour concrete into the formwork and tamp it carefully. It is recommended to use a vibrating plate for this purpose.
- The formwork can be removed after the mortar has completely hardened - 3-4 days is enough for this.
After making the foundation, you can lay blocks. This is how a strip foundation is built for a foam block house. Nothing complicated, but it is not always possible to do this.
Pillar Foundation
It is worth noting that this type of construction is ideal for our case. And if you are wondering what kind of foundation is needed for a foam block house, do not strain yourself and choose a columnar one. Supports must be placed so that they are at the corners of the building, as well as at the intersections of the walls. It is also recommended to reinforce with pillars and points with a high load. Please note that there should be a distance of no more than 2-2.5 meters between adjacent posts.
Work procedure:
- First you need to mark the places for the poles.
- Dig holes and lay a pillow on the bottom - sand, gravel, gravel.
- Waterproofing material must be placed over the pillow.
- Put shields in the pits, and then burst them. This is necessary so that the earth does not crumble into the pit. In addition, these boards are used as formwork.
- Carry out reinforcement - use rods of at least 12 mm. The fittings are located at a distance of 5-10 cm from each other. Fastening is carried out using wire.
- Before you start pouring, fasten the formwork. Mortar: three parts sand to one part cement.
- Pillars should be infused for two weeks. After that, you can remove the formwork and make a ceiling.
- Concrete floors are made in much the same way as the pillars themselves.
After the foundation is built, construction can begin.
Monolithic Foundation
But the construction of the foundation of a foam block house can also be done using monolithic technology. This is ideal for heaving soils. There is one drawback - you can not make a basement. Construction process:
- A pit of the required size is being made, the depth is not more than 0.6 m.
- At the bottom of the pit, you need to lay a pillow. It should have a thickness of 0.4 m. Of these, sand - 0.25 m and gravel - 0.15 m. A layer of waterproofing is laid on top of all layers.
- Put the formwork and pour the concrete solution.
- As soon as the solution is completely dry, the formwork can be removed and the waterproofing laid.
That's all, now you know which foundation for a foam block house will be the most optimal for all types of soils. The main thing during construction is to adhere to norms and consistency.
