When Is a Pile Foundation Necessary?

The first thing that building contractors must do before embarking on the construction of any building is to lay the foundation on which the structure will stand. There are numerous ways to lay the foundation of a building, but the choice of an appropriate method of installing a foundation for a building depends on site conditions and the specific requirements of each project.

One of the ways to build deep foundations for buildings is piling. Piling involves the installation of prefabricated post-like foundation members (called piles) to support a structure. Piles are made of wood, concrete or steel and can either be driven into the ground or placed into pre-drilled holes.

Pile foundations may generally be appropriate in the following conditions:

  1. When the water table is too close to the ground surface. If there is a perched water table below the ground at the construction site, excavation may not be a practical option because groundwater may quickly move into the dugout and fill it up. Pumping out the water can take a lot of time, especially during the wet season. Installing pile foundations helps to prevent water pooling in the trenches. 
  2. When on-site soils are weak and unstable. Before building contractors can determine what type of foundation they should use for a particular building, they must test the soil at the construction site. Soil testing is necessary to establish if the soil at a construction site can support the weight of a building, which will be passed onto the ground via the structure's foundation. If the soil at a construction site is found to be weak and unstable, then the only way to install a strong foundation for a building may be to use piling, which has the potential to reach very deep into the ground without destabilising the soil.
  3. When the cost of excavation for foundation installation is too high. When extensive excavation work is required to lay a foundation for a building, piling is the best alternative. Whether piles are driven into the ground or placed into pre-dug holes, they will significantly minimise the scope of excavation work necessary to have building foundations laid. This way, building contractors can avoid incurring high costs associated with major excavation jobs.

There are other conditions that may make it necessary to use pile foundations for building construction. Having a discussion with a piling contractor can help determine whether or not piling foundation is the best solution to your building foundation work needs.