Foundation settlement and failure can cause significant structural problems in a building if they are not fixed in time. The process of fixing foundation problems is known as piling and involves permanently integrating screw piles or concrete piles in the design of the building to provide a stable foundation. While these two materials can be used for remedying foundation defects, it is important to understand how they work, their merits and demerits before deciding between the two.

Screw piles

Screw piles are long tubes made of high tensile steel with a screw head that is screwed into the ground and a capped one that holds the structure. Screw piles do not require pre-dug holes; hence, they offer an efficient solution for foundation repairs. They also have the following benefits:

• No curing time is required. Once they have been screwed into the ground, foundation construction or repair work can commence immediately.
• Unlike concrete, screw piles do not shift or heave with the freeze-thaw cycles due to weather change.
• Installation of screw piles is quite fast. This translates into huge savings on labor costs.
• Screw piles can be extended or adjusted in case the ground conditions on-site are different from the projected ones.
• There is minimal environmental disturbance as there is less noise and vibration during installation.

Despite their numerous advantages, screw piles have a few downsides.

• They cannot be drilled through bedrock. If the foundation of the building sits on one, then alternative methods of repair must be adopted.
• Steel screw piles can be more expensive compared to concrete.

Concrete piles

Concrete piles are long concrete bars that are driven into the ground to support a structure and reduce the risk of foundation settlement and instability. Concrete piles are ideal for distributing the weight of structures and can be used in different configurations of various structures. They have the following benefits:

• Concrete is cost-effective compared to using steel piles. What's more, you will not need to invest in or hire costly construction equipment to lay them.
• They are ideal for shallow foundations that don't require time-consuming excavation processes.
• Pre-cured concrete is fast to install and repair work can commence immediately they are laid on the ground.

The use of concrete piles for foundation repairs has a few disadvantages:

• Uneven mixing of concrete and harsh environmental conditions can cause flaws in concrete piles and result in structural instability.
• Concrete is vulnerable to changing weather conditions and can shift and heave over time.
• Once set, concrete cannot be modified. In case of any changes in ground conditions, you may have to reconstruct the concrete piles.

Screw piles and concrete piles are both ideal materials for foundation repairs. However, screw piles are always a better option especially when time factor and durability are paramount to the project regardless of material and installation costs.