What is Underpinning and When is it Needed?

Seeing cracks appear in your home can be quite worrying. You might think that there was something severely wrong with your home and you’d be right to think so. Cracks appearing in the house are a sign that the foundation is weakening and the footing is compromised.

The best way to counter this is to look for a contractor or builder that offers underpinning services. To understand what underpinning is, we must first understand the foundation upon which most Australian homes rest. Almost all suburban Australian homes rest atop a foundation of soil that is supported by stumps that are secured to the bottom of the home. These stumps carry the entire weight of the home.

When these stumps start to rot they are replaced with stumps made from stronger materials like steel and concrete. The process of taking out the old stumps and putting in new stumps is called restumping or reblocking. But what if the soil on which the structure rests itself is compromised?

If the soil is laden with moisture then the clay starts to slightly weaken in certain areas which makes the footing shaky. This is known as slab heave. Fortunately, a slab heave is reversible as the footing is secure but for a temporary change in the hardness of the soil below. But what about irreversible damage? What if the soil on which the structure is built is starting to subside? The only solution for that is underpinning.

When the surface of the ground starts gradually sinking then it is known as subsidence. There is no possible way to reverse subsidence so the only option left is to restructure the ground with enforced footings made of either steel or concrete. This reinforcement is known as underpinning. A normal underpinning process would involve:

  • Digging new bored pier footings around the outside of the house
  • The old footing is excavated to make room for a stronger prop
  • The prop and pier arrangement is reinforced with steel bars
  • Concrete is poured in
  • Adequate space is left between the old footings and the new underpins
  • Once the poured concrete strengthens the new underpins will jack up the house

The underpins are not restricted to the outside of the structure. Sometimes the footings that are in the middle of a structure can also be underpinned. This requires excavating through the concrete slab to get to the loose soil at the centre.

If you require house underpinning in Melbourne then Titan Reblockers can get the job done. When it comes to underpinning, Melbourne suburbs have a growing need and we can help fulfill that requirement. Our work is guaranteed to produce results and we promise you’ll be satisfied with the job we do.

We also offer reblocking/restumping services so if you feel your suburban home is showing signs of a weakened foundation then don’t hesitate to reach out to a reliable and trustworthy builder service.