Home Renovation: Critical Options for Structural Underpinning

6 May 2016
 Categories: Construction & Contractors, Blog


The process of underpinning can be valuable during major renovations of your old home. Basically, this involves reinforcing the base structure or foundation of the house. The process is used as a serious measure against deterioration of the building to prevent structural breakdown. You should consider choose the underpinning process if a building inspector has determined that your home has a poorly-built foundation. Natural occurrences like earthquakes and floods can also weaken your structure. In addition, the house base should be strengthened if you want to increase the load capacity for a new floor. Here is a description of the critical methods for underpinning that you should consider for your home.

Traditional Excavation Method

The traditional method for underpinning has not changed over the years because it is highly effective in restoring weakened or broken foundations. Basically, this technique uses concrete as the main building material for the reinforcement process. The contractor will need to excavate the ground around the base of your house to expose the damaged areas. The depth of digging will depend on the structural design of the home and the extent of damage. The formed holes are filled with mixed concrete to create a more reliable foundation. This underpinning process will allow you to continue using the house during the renovation duration.

Resin Injection

Resin injection underpinning is a relatively new technique compared to the excavation alternative. The strategy for structural improvement is considerably similar, but this option uses modern resins instead of concrete. Moreover, the process is relatively simpler and less labour intensive. Your contractor will require some structural-grade resin and corresponding hardeners for the project. These will be combined together and inserted beneath the footing of the foundation. The mixture will expand as a chemical reaction between the hardening agent and the resin occurs. Consequently, the cracks and other voids in the foundation will be filled to reinforce your building. Resin injection is non-disruptive and your project will be completed fast.

Brackets and Screw Insertion

The house foundation can be underpinned with screws and brackets when the damage is not extensive. This is an ideal option if there is minimal space around your home which can limit the possibility for deep excavation. For this process, the builder will require structural-grade screw piles and compatible brackets. Next, light digging will be performed and the piles and brackets will be inserted manually by the crew into the foundation to join the cracks and faults. The installation process can be performed using a mini-excavator arm for larger projects.