House on stilts. Which is better: a house on screw or wooden stilts?

In the world in almost any country you can find a house on stilts. In some parts of the country, houses are built on wooden logs, buried vertically in the ground for centuries. This technology allows you to build housing even on the water. In recent decades, no one is surprised by the house on piles made of concrete. In modern construction there has come a real revolution after the use of screw piles for the construction of light buildings.

General information

A house on stilts is an ideal solution to the problem of construction where the soil does not fit the monolithic ribbon foundation. It can be built on sites with the following features:

• with the previously created landscape;

• with a difficult relief;

• with high humidity of the ground;

• where it is impossible to excavate;

• in areas with a deep freezing level of the soil.

The construction of houses on stilts is very popular today, but metal supports, which give the chance to erect quickly small buildings with own hands, are especially in demand. The advantages of such buildings are:

• saving time and cost of construction;

• the possibility of carrying out work on problem soils;

• no need for soil leveling;

• the possibility of erecting wooden structures on lawns, slopes, near trees;

• high piles protect the house from penetration of rodents;

• during the flood the dwelling is protected from possible underflooding;

• the use of high piles makes it possible to use a site located under the house for parking a car, a summer kitchen or a sports ground.

House on wooden stilts

Despite modern achievements in construction, some ancient ways of erection of buildings are successfully used to this day. A house on stilts made of wood is a typical construction method, popular in many states. So in Russia many centuries wooden houses were erected on logs of wood. They were often called "chairs". For such piles are used trunks of those tree species that are characterized by a long period of operation. These include pine, oak, larch. The minimum diameter of such "chairs" for creating a reliable foundation is 20 cm. The more it is bigger, the better. To extend the life of wooden piles, they are subjected to fire treatment - they are burned. In the ground, the scorched wood badly rotts, which allows building structures with a lifespan of many decades (at least 30 years). To date, the processing of piles with fire is often replaced by impregnation with special antiseptics or bitumen coating.

Since today there are enough available high-tech piles made of metal for sale, the construction of houses with logs is taking a back seat. Most often they are used for dacha frame or wooden structures.

A house on stilts, the photo of which is on top, would require digging a fairly deep pit under the logs. The minimum depth for digging wooden piles is 1.25 m. They should rest against bars with a section of 10x20 cm and a length of 40-50 cm. Wooden piles are in all corners of the structure and are located along its perimeter (with a distance of 1-2 m). Backfill pits are produced in layers of 20 cm. Each of them is carefully rammed. The top 30-40 cm of the backfill is produced using fine granite gravel or gravel.

Disadvantages of wooden piles

Despite its popularity, wooden piles have been losing ground in recent years. This is due to such factors:

• difficulty logging;

• the need for additional wood processing;

• short life of piles compared to other products of this type;

• the sale of more high-tech building materials;

• high price for quality wood.

Pile-screw foundation

The foundations erected with the help of screw piles were used for a long time for the construction of military facilities. This specialization is due to the fact that their design allows you to build reliable supports for a variety of buildings in the shortest possible time. Abroad, modern technology of building buildings on pile foundations was mastered dozens of years ago. It is used for the construction of residential buildings, farm buildings, as well as various industrial structures.

In the Russian Federation, these bases have been used for a long time exclusively for the construction of lightweight structures, since the screw piles available for sale were characterized by low load-carrying capacity. Recently, modern varieties of metal supports have appeared that make it possible to make the scope of such building materials much wider.

Every year more and more Russians build the foundation of the house on piles. This is due to the improvement of the quality of this building material and its democratic price. The house on screw piles, reviews about which most of its owners have only positive, can become an ornament of any site. Most often it is a light structure made of wood. To this kind belong and frame houses, and buildings from other non-heavy building materials. Screw piles are used for the installation of playgrounds, baths, saunas, fences, arbors, greenhouses, terraces.

General information about screw piles

Screw piles under the house - the main element of the foundation. They are a steel pipe, the metal thickness of which is not less than 4 mm. On the one hand, it has a sharpening. At this end of the pile is a cutting blade, with which the support is screwed into the ground. Many people think that the use of such building materials will require the use of special equipment. In fact, the ideal shape of the blades of the screw piles allows them to be screwed into the required depth by 3-4 workers.

For construction of objects with differences in height or with the presence of various lateral loads, piles having two blades are used. This design gives the foundation additional reliability. The diameter of the blades of the screw piles varies in the range of 200-850 mm. The supports themselves have a diameter of 50-350 mm. The length of the screw piles can be 2-11 m. There are not only hollow, but also solid piles on sale.

Advantages of screw piles

Anyone who has already built a house on stilts, reviews about them leaves mostly positive. The main advantages of these building materials are:

• possibility of repeated use, due to easy dismantling without damage;

• no need to perform significant amounts of excavation;

• the possibility of erecting houses in mobile and watered areas;

• speed of erecting the foundation;

• the beginning of the construction of the building immediately after the foundation;

• the possibility of using various extensions for construction;

• Long service life, exceeding 100 years;

• an acceptable cost, which is almost three times less than the price of the strip foundation;

• absence of construction debris on the site;

• the possibility of replacing or repairing the foundation.

Due to the optimal perpendicular arrangement of the blades, the screw pile, when screwed into the ground, does not loosen it. The bearing capacity of such building materials varies in the range of 5-25 tons. Piles with cast-iron tips are chosen for construction. The best protective coating of such supports is made on the basis of polyurethane resin. Very reliable galvanized piles, covered with protection from the outside and inside.

The cost of the foundation of the screw supports depends on the size of the house. So, for example, the construction area of 6x6 m will cost 1-1,2 thousand dollars, and 9х12 m - 3-3,3 thousand.

Disadvantages of screw piles

Despite the fact that there are not enough shortcomings with these building materials, they still exist. Those who built a house on stilts, reviews about them leave mostly positive. Among the most common shortcomings, most developers distinguish:

• inability to use on rock or coarse clastic soils;

• deformation of the foundation, possible in case of a violation of the technology of the device. It occurs when, during screwing in the piles, their position was not fixed, the strapping was done incorrectly, the screws were hammered or installed in excavated pits;

• subsidence of soils, resulting from a poor-quality survey of the site;

• corrosion of piles with poor quality of anticorrosive environment;

• impossibility to build large houses using heavy building materials.

Variants of pile-screw foundation projects

There are several options for the projects of such foundations. They are selected depending on the type of future house and soil on the site. The most common of the foundations projects:

• Single piles supporting individual building elements used when a small extension is made to an existing building;

• a standard foundation, which is erected under the main elements of the building;

• pile tape, located under all walls of the house;

• pile field, necessary for the construction of a foundation for heavy structures.

Building a house on a pile-screw foundation

The house on the screw piles is built in several stages:

1. The construction of the structure and the calculation of the number of screws are made. Most often under the frame and wooden houses choose piles with a diameter of 108 mm. For small buildings, you can choose smaller screws, which will save money. When calculating the required number of piles, remember that with too often installed supports, the foundation's reliability does not increase substantially, but its cost significantly increases. One pile after filling it with concrete can withstand a load of 5-9 tons, so the distance between them when building frame houses can be 3-5 meters. The number of supports is increased when building two-story buildings or using more heavy building materials. To increase the reliability of the pile-screw foundation, its bearing capacity is increased by 25-30%.

2. The site is marked out and pre-prepared.

3. The type of foundation is chosen depending on the mass of the construction being constructed, the type of soil and the depth of its freezing. Begin construction with geodetic study of the soil. It is necessary to determine the location of groundwater and stable seams.

4. Piles are screwed into the ground according to the produced marks. In the vicinity of the screw, there is soil compaction, which contributes to strengthening the strength of the foundation. These works can be carried out in any weather. I screw in at least 3 workers: one monitors the level of support, and the other two screw it to the desired mark. The supports are cut at a single level and poured with concrete. It enters the pile tube, which strengthens the pile and prevents corrosion of the metal. After the concrete freezes, they move to welding to the support of the metal head.

5. It is necessary to bundle the piles for an even distribution of the load. Most often it is made of a channel. The top part of such a foundation is called grillage. It redistributes the load of the load-bearing elements of the structure.

6. Warming of the pile-screw foundation is not required, since it relates to the ventilated type. Sometimes the insulation of the grill is made, but if the work is not done properly, moisture may appear on the entire building. It is best to heat the house in the house to insulate the floor of the house.

7. Prefabricated pile foundation erected skeleton or wooden houses.

8. The basement of the foundation is made hinged.

What house on piles to choose?

Weighing all the pros and cons of choosing one or another type of supports, we can say with confidence that the modern pile-screw foundation has more advantages than the wooden one. He surpasses the latter not only in terms of technical, but also in terms of economic and labor costs. At the same time, its durability is many times greater than the service life of log supports.