The foundations of your home are what support its weight. Not only this, but foundations provide the necessary footing to ensure that your home's walls don't start to move sideways if the land they are standing begins to move. This can happen for all sorts of reasons, such as soil erosion, for example. Of course, if you are remodelling your home's interior, then you may not need to improve your foundations by underpinning them. However, where new external walls are to be added or where load-bearing walls will be removed, underpinning services will probably be required. When might you need them and what is involved?

When Is Underpinning Necessary?

In some cases — especially with older properties — the foundations are insufficiently deep or have deteriorated. You'll usually see this if cracks begin to appear in your walls. If left unattended to, the structural integrity of your house can be undermined. Underpinning them provides an extra foundation layer that the structure can sit on. When it comes to remodelling, you may be adding extra weight to your foundations by beefing up a wall or even adding a storey. Some walls may come down which means that additional weight is added over specific foundations. Either way, underpinning what is there will mean the project can continue without subsidence laying in store for you down the line.

What Is Involved With Underpinning a Foundation?

If you want to strengthen a foundation that is already in the ground, then you need to dig a trench beside it. Once this has provided the necessary access, earth is dug out in small sections, or boxes, beneath the current footing. This gap can then be filled with concrete which, once it hardens, provides the desired underpinning. Remodelling contractors can often do this work because much of it can be carried out by hand or with the use of a mini-excavator.

How Can Underpinning Cause Less Disruption?

If digging a trench is not practical — because you are underpinning a foundation that is beneath the main structure of your home, for example — then you can use a less disruptive method. This does not involve excavation work, but holes will need to be drilled into the foundation. The holes are then injected with a special resin and other chemicals that bond hard once they make contact with one another, thereby underpinning the structure. Usually, such underpinning services are provided by specialist contractors. This makes the process more expensive than simply digging down but it is less messy and often much faster to deliver.