Myths about screw piles Quite a lot is known that scares away private developers. But there are also real problems associated with the unstable position of the house - its subsidence or loosening. Most often, troubles arise due to incorrect calculations bearing capacity, non-compliance with the technology for installing pile pillars or the lack of a real hydrogeological study of soils. But it is not always the builders or designers who are to blame when a house on screw piles suddenly begins to wobble. Often the cause is the piles themselves.
Why does the house rock?
Several factors may contribute to this:
- high location of piles above ground level;
- incorrect strapping device;
- insufficient screw-in depth;
- small diameter or thin wall of metal pipes;
- poorly made blades;
- making a pit that is too deep;
- installation of an insufficient number of supports under load-bearing walls;
- exclusion from calculations of corrections for weak characteristics of soil layers;
- lack of heads;
- performing work in winter time;
- insufficient spatial rigidity frame structure ground part of the building.
Each of the reasons causes different consequences, which ultimately influence the fact that the house on stilts begins to sway. For example, due to incorrect determination of the bearing capacity of the soil or external load the building begins to sag. And the result of small deepening of the blades, when they fall into the freezing zone, can be the bulging of screw piles due to the influence of frost heaving forces on them. In this case, the house or its individual corners will rise above the ground in winter, and lower in spring.
To avoid problems associated with insufficient screwing of piles, the procedure for trial installation of 2-3 supports on the site being built will help, although there is an opinion that this way only determines the presence of stones in the ground.
If a house installed high above the ground (more than 40 cm) is shaking, then diagonal tying of screw piles will help correct the situation. As a rule, it is performed from metal profile, which is placed obliquely between pipes protruding above ground level. IN in this case The rigidity property of the triangle figure is used. All piles are subject to strengthening, regardless of what walls they are under.
The dimensions of the pipes affect the bearing capacity of the supports, which must be taken into account at the stage of calculating the number of piles for the foundation. Their number and diameter are inversely proportional to each other. An imbalance leads either to an overexpenditure of material resources or to a weakening supporting structure buildings. In the latter case, subsidence and subsequent swaying of the structure occur due to the loss of the design position of the screw piles.
The reason that a house on screw piles begins to wobble is often the absence or inadequate strength of the horizontal frame (grillage), as well as its partial destruction. This design must be carried out in accordance with the design. Violation of integrity can occur due to non-compliance with the technology of the strapping device or in the case of the use of low-quality, cheap materials. It should be remembered that savings are not allowed here.
The issue of excessive thrift also applies to the acquisition of screw piles. Preference should be given to products famous brands. It is not recommended to install the house on supports made independently or at home-made enterprises, just because the low cost of the products suits you. Factors influencing the swaying of a structure can be:
- fallen off blades;
- thin walls of a metal pipe;
- lack of a high-quality protective layer, which contributes to the emergence and development of corrosion processes.
The construction of buried pits when installing screw piles under a house deprives the pipes of a significant part of the vertical supporting surface. No matter how carefully the compaction of the backfill is carried out, the density of the compacted soil cannot be achieved. Over time, the supports will begin to loosen, causing the house to sway. Installing spacers or wedges will help correct the situation.
Photo taken from the site http://inf-remont.ru/
A similar situation often arises in the case of screwing piles into frozen ground, which loses its strength when thawed. When installing foundation supports in winter, experts do not recommend immediately loading them with the frame of the house. You should wait for a thaw and adjust the position of the pipes. This advice does not apply to regions with permafrost soils.
The reason for the instability of the position of a house on stilts may be the lack correct fastening frame of the ground part. Often, installing diagonal supports between posts or additional fasteners will eliminate defects that cause swaying. In this case, problems are not associated with the foundation.
The choice of an acceptable option for strengthening loose piles should be left to specialists capable of conducting professional expertise.
Installation errors
It should be noted that a house on stilts will last a long time and will not create problems only if the foundation is laid out correctly. It is better to leave independent screwing of screw supports for the construction of non-critical outbuildings and installation of fences. It is recommended to trust the execution of foundations for capital, especially residential, facilities to experienced construction crews. You should avoid collaborating with civilian covens who offer their services for a small fee.
One of the mistakes of careless workers is rocking screw supports during screwing. Pipes in this way supposedly penetrate the ground more easily. But this is a gross violation of the technological process. Such a house on stilts will begin to rock, if not in the same year, then in a couple of years - for sure.
Another significant deviation from the rules is the digging of deep pits and subsequent rotation of the piles to the height of the blades. There are cases when “experts” dig holes up to two meters deep, which is unacceptable! The sinuses filled with soil will sag after the first rain, which will lead to the rocking of the house on stilts.
Properly executed pits have a depth of 20-25cm.
Another violation relates to the wall thickness of metal pipes. For residential buildings You should choose products larger than 4mm. No less important point it is mandatory to fill the internal cavity of the pile cement mortar, which greatly enhances the strength of the structure. Filling is done after screwing in the supports. There are cases when it is abandoned purposefully or out of ignorance, which leads to the rapid appearance of rust on the internal surfaces of pipes.
The following will help protect a house on stilts from swaying as much as possible:
- thorough hydrogeological study of soils;
- concreting the base, performed immediately after installation of the piles and trimming of the heads;
- step-by-step quality control of completed work with recording of the process on a camera or video camera;
- desirable presence responsible person when installing piles;
- compliance with the “exposure” of the foundation during the winter period.
It must be remembered that the capital construction and long life of the house depend on the correct adherence to the technology for constructing an underground structure, so the work should be approached seriously and without total savings. The problem of a house on stilts being loose should not deter potential developers. Such troubles happen quite rarely and in most cases are successfully resolved.
There is debate among builders about the need to perform a trial screwing of piles. Some argue that the results of geological research are quite sufficient. Others assure owners that samples need to confirm the real soil conditions on the site, and without them quality installation support pillars simply impossible. It should be noted that performing both types of work does not make sense, and preference should be given to qualitative research, despite the fact that it will cost much more.
Test screwing does not provide correct information about the thickness of the solid soil layer and its load-bearing capacity, unlike laboratory conclusions.
Common Myths
Myth – the process of installing piles is quite simple. In fact, they are screwed in quickly, but preparation for work takes a long period. In particular, this applies to the actual assessment of geological conditions. Difficulties when screwing in occur when:
- the durable layer lies below seven meters;
- there are stones in the ground big size– piles can “move away” from the vertical axis, which subsequently affects the swaying of the structure.
Myth – the metal shell rusts within 10 years. This can happen if the section of the pile located above the ground is not treated with anti-corrosion compounds. In the ground, there is no sufficient flow of oxygen for the oxidation process, so rust appears too slowly. Sufficient wall thickness will not allow metal pipe collapse within 10 years.
Myth - piles will last 300-400 years. There is no such data, since screw supports appeared about 200 years ago. Manufacturers give guarantee period 50 years.
Myth: When screwed in, the blades break off. This drawback can only be attributed to low-quality products. When purchasing piles, you should make sure that weld is homogeneous, has no shells or sagging. There are also cast tips on the market, from which the blades cannot come off under any circumstances. The quality of piles is judged by their uniform coloring and the absence of rust on the inner surface.
Myth – installation can be completed in one day. This statement applies only to open areas where plastic soils lie. The presence of trees, nearby buildings and hard layers soil increases the time for screwing in piles.
Myth: Products made by different manufacturers are the same. This idea of piles is incorrect, despite their standardized sizes. The differences lie in the grade of steel, wall thickness, types of outer coating, location of the blades, etc. All this is reflected in the cost of products.
Myth – pits don’t have to be made. In this case, starting the screwing process will be difficult. A pit is needed, but not deep.
Myth – a channel or I-beam is required to perform the strapping. This is wrong. Metal can be easily replaced wooden beam which will cost less. But it is not recommended to use it when the house is located high on stilts or in the case of massive walls. A smart approach to materials is required.
Myth - if a pile wobbles, it just needs to be buried. Such a solution does not always eliminate problems.
Myth – thin piles can be installed under a lightweight house. In fact, they are intended for fences, gazebos, greenhouses, etc. Having installed a small house on piles with a diameter of 57 or 76 mm, you should expect it to sway from gusts of wind. Even piles with a diameter of 89 mm are not suitable for houses built on soft ground. Thin supports can be used for porches or attached terraces.
Myth – when reconstructing a foundation, piles can be screwed in at an angle and then aligned vertically. This option will definitely deprive the pipe of stability on one side, loosen the soil at the base under the tip and can deform the blades. In this case, it is unlikely that the house will be able to shake.
In our country, screw piles have only recently begun to be used in private construction, but in the West the technology has been known for more than one century. Many owners of houses on screw piles are quite satisfied with their choice. They indicate that they are not familiar with distortions, cracks and swaying. But their homes were built with strict adherence to technological processes!
Frame house- this is a structure that can be not only country house: By frame technology warm, reliable cottages, dachas, houses for permanent residence. Moreover frame houses They perform well even in those regions of Belarus where winters are very cold and snowy. However, there are also cases when a frame house cannot withstand not only winter snowstorms, but strong hurricane winds. This happens due to the inexperience or dishonesty of the builders: destruction frame houses happens because of the mistakes they make.
Frame house after a hurricane
In particular, a story happened in the Moscow region, after which a family was left without three houses, which were built by the same construction company.
During the hurricane, wind speeds of 20-27 meters per second were recorded. With such a wind, many dry trees were knocked down, but besides them, there were also three houses that belonged to the same family. One of them collapsed completely, folded like a cardboard, two more had their walls and roofs torn off. All three houses were built by the same people, who refused to admit that the houses fell into disrepair through their fault - the builders cite the hurricane and the fact that the houses were not designed for such winds. However, their customers recall that before construction they were assured that frame houses would serve perfectly - both in summer and winter. Construction took place less than a year before the hurricane.
A frame house will indeed serve, but only if it is built in compliance with all rules and technologies. In this same case, several fatal mistakes were made during construction.
Why did the frame house collapse from the wind?
The first gross mistake of the builders was that they did not provide sufficient rigidity of the frame, which is required according to regulatory documents. To ensure rigidity, it is necessary to use OSB boards for sheathing or to embed jibs. The jibs are cut from bottom to top so that they combine several racks. The jibs are placed diagonally and, as it were, connect the house, thanks to which the geometry of the frame is maintained.
This problem had its symptoms even before the house collapsed. Residents said they felt as if the house was swaying when someone walked up the stairs. They reported this to the builders, but calmed down when they were assured that this was just a consequence of the house shrinking. But the point is that frame construction involves the use of dry boards, and a frame house built correctly will not shrink.
A jib was still found in one of the walls, but it was not installed diagonally, it ran along only one section, so it simply served as an additional stand and did not perform a load-bearing role.
Builder mistakes
There are other mistakes due to which these houses would not last longer than 10-15 years.
How to avoid becoming a victim of unscrupulous builders?
You need to take care of the safety of your homes yourself. Unfortunately, there are unscrupulous builders who do not comply with all technologies and use low-quality, cheap materials during construction. They usually lure customers with cheap houses.
The state does not control low-rise private construction and does not issue any licenses. Therefore, if something happens, there will be nowhere to complain.
When starting construction, you must either independently study the nuances of frame technology, or hire a third-party technical specialist to provide supervision.
We not only publish good feedback about frame houses from those who live there, but also negative ones. After all, like any technology, frame construction has its pros and cons. This concerns the construction of the residential building itself.
It also has its positive and negative sides for the residents who live in it.
Pros and cons of frame construction
If we talk about the construction process itself, the undoubted advantages of this technology include:
- Speed of building construction.
- The relative cheapness of all processes - from arranging the foundation to insulation.
- Possibility of erecting a building without a strict design.
The disadvantages that appear during the construction process include constantly rising prices for façade and thermal insulation materials, and also not the most high quality performance of work by contractors.
As in any matter, you yourself have to monitor how your contractors work and what materials and how they put the walls and ceilings in your home.
Reviews from residents living in frame houses
If we consider reviews of frame houses from those who live there enough long time, then we can also divide the responses into positive and negative.
The advantages of living in a frame house usually include low operating costs for maintaining the house, as well as the ability to monitor the condition of virtually all its structural components - from walls to ceilings.
After 2-3 years, you can safely dismantle part of the sheathing or floor and check the condition of the insulation or membranes used. It would be completely impossible to do the same with a brick or block house without destroying the structure.
Negative reviews about frame houses from those who live there mainly arise when the technology for constructing a frame structure was violated at some stage.
Here are some of the reviews:
Roman Senyavin, Vologda: We have been living in a frame house for 3 years. We bought a ready-made one from the company at small area. House on a wooden frame with cotton wool insulation.
The house is constantly damp. In spring and autumn, you can tell it’s dripping from the ceiling - such is the humidity in the house. They called for an examination, they said normal ventilation should be done. And this means we have to break everything down and do it all over again.
Here is another review from a person living in a frame house:
Andrey Skryabin, Chelyabinsk: Friends suggested that we move to their village. We bought a plot next to them and hired a crew to build a house.
A friend of mine has a house made of foam blocks, and we wanted to build the same one. But we were convinced that now we need to build a frame structure, it is cheaper and costs less.
We fell for these conversations. They built us a house, which we moved into 2 years ago. To say that we were deceived means to say nothing.
The frame house is shaking! When a strong wind blows, the walls move noticeably. All the finishing, plaster, wallpaper, everything is cracking! And this is in a new house. What will happen in 5 years? Will it completely fall apart? We will sell and move into an apartment.
Conclusions on negative reviews
If you have been studying the issues of private construction for several days, then you should already understand what technological violations were committed.
In the first case, the supply and exhaust ventilation was not calculated and properly executed.
In the second case, it is not entirely clear from the review what frame the house is on. But if you mean wooden frame, then 3 options are possible:
- The slab cladding material is not suitable for the given house or was installed incorrectly.
- If the planking is done, then it is not made at 45 degrees.
- The jibs in the frame were installed in violation of technology.
And, as a result, there is no rigid frame that should provide strength to the entire structure.