Screw piles: pros and cons. Tips for selection and scope

Screw piles are steel pipes that end with a blade and a pointed tip. They are screwed into the ground like screws.

An important part of the pile is the tip, since it performs several functions at once:

• Is the supporting part of the pile;
• Transfers the load to the ground;
• Prevents the pile from pouring out of the frozen ground during the winter swelling.

The problem from the last point is most often encountered in the construction of lightweight wooden structures, using piles of short length. The only way to avoid encountering swollen soils is to penetrate the foundation of the house below the freezing line in the construction region.

Where to use screw piles?

Prefabricated inexpensive bases for light frame structures - that's where screw piles are used, the advantages and disadvantages of which will be discussed below, but for now we'll deal with their size.

Under what house what piles?

For individual construction, the following types of piles are most often used: SV89x250, SV108x300, CB133x350. This abbreviation stands for a screw pile with a barrel diameter of 89 (108, 133) and a helical blade diameter of 250 (300, 350). The smaller the pipe radius, the lesser loads can be trusted to it. If we are talking about light fences and small garden buildings, a 76 mm pile will fit; About verandahs, gazebos and brick fence poles - 89 mm; About small frame or log houses - 108 mm. Well, finally, if you plan to build a spacious wooden house or even a foam block, then for this case you need piles with a barrel diameter of at least 133 mm.

Like all building materials, screw piles have negative reviews , but they are dictated no longer by the unsuitability or unreliability of this kind of foundation, but by improper application. Any construction requires a professional look and at least consultation, and as a maximum - an accurate detailed calculation of all structures and loads.

Screw piles: pros and cons

The erection of a foundation on screw piles has many advantages, such as:

• They are quick and easy to assemble, since they do not require preliminary drilling and concreting;
• It is possible to engage piles during the whole year;
• For them is absolutely not complicated complex relief, bulk soils;
• They are produced serially in factories, which means that their cost is much lower than for traditional types of foundations;
• They can be repeatedly twisted and twisted;
• They have good resistance to winter ground drills.

Considering screw piles, pros and cons of these designs, it is impossible not to mention that from year to year they are becoming more popular. And sometimes there are situations that can not be avoided without them.

In contrast to all that is said about screw piles, the disadvantages are what they have in comparison with their concrete "brothers": they have a shorter service life due to their susceptibility to corrosion in a humid environment, especially if their manufacturer uses poor-quality materials and processing methods .

In general, the life of the piles depends on many parameters that must be observed: on the thickness and grade of steel, on how professionally the seam that joins the trunk with the blade is professionally made, on the quality of the anticorrosive coatings and on the mineral composition of the soils. If there is a desire to purchase quality products, then it is necessary to demand all passports, certificates and documents confirming the conduct and results of all the proper tests.

Depending on how to exploit screw piles, the pros and cons can manifest to a greater or lesser extent. For example, if the pile is used as a grounding method, then it will collapse and rust more likely, because in the case of a break in the zero conductor, the current will flow directly through the body of the structure. Can receive screw piles negative reviews in the event that the house is built within a radius of 50 meters from a power plant or cell towers. In such an area, a phenomenon called a wandering current is observed in the soils , which accelerates electrochemical corrosion.

Types of screw piles

Depending on which screw piles are used, pluses and minuses, reviews about them can vary. There are 2 varieties: with a welded tip and with a cast (in this case the pile is an integral structure). The second option is more expensive, but more reliable, because the weld is the most vulnerable place of the product.

Virtually all negative reviews refer specifically to welded piles, because they are usually made in handicraft conditions with non-compliance with standards and GOSTs.

How to choose the right piles?

Use welded can be in the event that you need to build minor structures like fencing and household structures. In other cases, it is necessary to give preference to cast, made of galvanized pipe. Anticorrosion treatment of the blade will not solve the problem, because during screwing, the friction is so high that all the coatings are easily erased.

In order not to be disappointed in screw piles, you should purchase them only from trusted suppliers, whose quality you are sure of.