Typical mistakes when re-installing screw piles

Even if the piles appear intact and have passed inspection, errors during reinstallation can ruin all the efforts. It's crucial to follow the proper procedures; otherwise, the foundation will be tainted, and warping or settling will begin within a few years.

1.       Installation without checking the metal's condition

Some contractors save time by immediately reinstalling piles without inspecting them thoroughly. This results in foundation components with corrosion or microcracks that may not withstand the load.

2.       Incorrect geometry during dismantling

 If piles were pulled out with a crane or crowbar rather than carefully unscrewed, the blades often bend. When reinstalled, these components do not ensure firm contact with the ground, and the building may "bounce" under the load.

3.       Using piles of different lengths or diameters

Sometimes contractors try to combine old and new piles. This is a serious mistake: different parameters mean different load-bearing capacities. In this case, the foundation works unevenly, and the house may settle on one side.

4.       Reuse in dense or rocky soils

 If the soil is heavy, re-installing the same pile almost always results in the blade breaking. The metal is already weakened, and the load on the cutting edge is higher during the second installation.

5.       Lack of corrosion protection before reuse

Even if the pile remains intact, it must be treated with an anti-corrosion compound or zinc coated before reinstallation. Without this, its service life will be significantly reduced, especially in wet soil.

Pros and cons of reusing screw piles

Like any construction practice, reusing piles has its strengths and weaknesses. Sometimes it's a smart way to save money, while other times it's a risk that can lead to costly repairs. Let's look at both scenarios.

Advantages:

•        Budget savings. New piles make up a significant portion of the foundation cost. If the old ones are in good condition, you can save up to 30–40% of the estimate.

•        Quick installation. With reuse, you don't need to wait for new piles to be delivered—it's enough to inspect and prepare the existing ones.

•        Environmentally friendly. Reusing piles reduces scrap metal and waste, which is especially important during the construction of temporary structures.

•        Suitable for mobile and prefabricated structures. If the building is intended to be dismantled and moved (for example, a pavilion or utility room), reusing piles is a viable option.

Disadvantages:

•        Risk of reduced strength. After removal, the metal develops microdefects, and the protective coating is damaged. This reduces the service life.

•        No warranty. Reinstalled piles are rarely covered by a warranty—neither manufacturers nor installers can guarantee their performance in new soil.

•        Not suitable for permanent structures. A house or extension requires maximum reliability. Even minimal loosening of the piles can lead to warping or cracks in the walls.

•        Additional inspection costs. To ensure suitability, diagnostics, cleaning, and treatment with anti-corrosion agents are required—and this also costs money.