Which material is typically used for underpinning foundations?

Reinforced concrete is typically used for underpinning foundations due to its strength, durability, and ability to bear heavy loads. Underpinning is a construction process used to strengthen and stabilize the foundations of existing structures, particularly when there are concerns about settling, shifting, or structural integrity. Reinforced concrete combines traditional concrete with steel reinforcement bars, enhancing its tensile strength and making it suitable to withstand the stresses that may occur with foundation work.

While steel beams can be used in construction and may serve specific roles in foundation modifications, they are not the standard choice for underpinning. Concrete block, while strong, does not provide the overall load-bearing capacity and stability required for underpinning as effectively as reinforced concrete. Wood planks lack the necessary durability and structural integrity for this application, especially for long-term foundation support. Therefore, reinforced concrete remains the preferred material for underpinning due to its effectiveness in supporting and securing existing foundations.