Installing foundations for our constructions and structures is a practice as old as history itself! For thousands of years humans have used piling or other methods of setting a sturdy base upon which to build their homes or other community buildings. Foundations can be set either shallow or deep into the earth, depending on the needs of the project and the conditions of the surrounding soil. But what’s the difference? The main difference between shallow and deep foundations is, obviously, the depth. Deep foundations are usually any deeper than 3 meters below ground level but can stretch to 100 meters deep! Shallow foundation are those that sit on the surface or only reach one or two meters deep.
Let’s take a quick look at some of the other notable differences between shallow and deep foundations:
Shallow Foundations
Shallow foundations come in a few different variations. Pad foundations are shallow foundations in their most basic form: a large slab or ‘pad’ of concrete or other foundational material is set at the base of a large column to support a load. Strip foundations consist of several pad foundations linked together as one long base for a line of columns or a load-bearing wall. Finally, raft foundations take this principle and expand it even further, spreading the load of a column or columns over a larger area or the entire surface area of the structure.
Deep Foundations
Deep foundations are common for large structures, or those being built on unreliable soil. Deep foundations are used to transfer the load to a more solid layer of soil or rock deeper in the earth, or to the surrounding soil through friction.
The most common form of deep foundations is piles. Piles are long supports used to bear the weight of the building and transfer it to the earth. But other variations include pier foundations, which are built on top of piles, using large cylindrical columns to raise the structure off the ground. Caisson foundations are constructed at ground level and then lowered to the required depth by excavating material from within the Caisson, allowing it to sink.
Think you may have potential subsidence occurring at your property? Get in touch to see how our mini piling services can help.
