Foundation underpinning is a process that strengthens the foundation of an existing building. Over time, the foundation of a building can break down and become unstable. This is often due to the age of the building, but additional causes stem from changes in soil properties and changes in soil properties. In these cases, underpinning can restore the strength of a foundation and prevent further deterioration.
Signs Your Foundation Needs Underpinning
It’s not convenient, or even possible in most cases, to lift up a building and examine its foundation for deterioration. For this reason, it is critical to know what external and internal signs to look for when determining whether a building requires underpinning.
Outside a building, it is possible to evaluate the strength of a foundation by looking for cracks. Cracks near windows or doors may indicate a faulty foundation. In particular, horizontal cracks and “stair step” cracks are signs of a serious foundation problem. Inside a building, evaluate the foundation’s strength by looking for cracks in the floor or walls. If there is a crawl space, inspect the space for dirt, moisture, or a musky smell. Any of these may indicate that water has breached a foundation.
Types of Foundation Underpinning
If you’ve determined foundation underpinning is needed, the next step is to consider the type that is appropriate for your home or building. There are four main methods of foundation underpinning.
Concrete
Concrete foundation underpinning is the most traditional form of underpinning. This process involves pouring concrete into hand-dug boxes. As a result, an existing foundation is fortified with the addition of poured concrete, an effective solution for shallow foundations. Though this process is simple compared to other methods, concrete foundation underpinning is a time consuming and expensive process. This solution requires ample access to a building’s foundation. This method is not ideal for foundations with base depths greater than three meters or water-logged ground.
Beam and Base
Beam and base underpinning involves the use of a reinforced concrete beam that is placed above or below existing footing. Alternately, this type of underpinning can replace footing altogether. This beam acts as a load-transference tool, which enables building load to be relocated to concrete bases. Beam and base underpinning requires more advanced technology than concrete underpinning, but is just as costly and time consuming as the concrete method.
Mini-Piled
Mini-piled underpinning combines multiple techniques to support a foundation. In this process, pile and beam, piled raft, and cantilever pile-caps are used to quickly complete the underpinning process. Mini-piled underpinning is ideal for structures with limited foundation access, environmental pollution concerns, or when minimal building movement is required. Since this process does not require mass excavations, it is often quicker than other underpinning methods.
Minimally Invasive Underpinning
This type of underpinning injects resin into the building’s foundation underneath the footings. Because this is the newest method of underpinning, this practice is not yet widely used. An advantage to minimally invasive foundation underpinning is that it can be completed quickly without disturbing a structure. Also, this method addresses both soil and foundation concerns.
If you’ve noticed cracks or have concerns that your home needs a foundation underpinning, do not wait until it becomes a safety hazard. Call Intech Anchoring Systems today at 844-244-7319 to learn more about how we can fortify your foundation.