The Underpinning
Are you looking to increase the height of your basement? Or have you discovered that your foundation has degraded over the past number of decades and requires reinforcing? Why spend the additional money on your basement?
If the foundation requires reinforcing you don’t want to stint on fixing the issue, which if poorly remedied could cause an imbalance within the structural integrity of the foundation, supporting walls and the entire building. In today’s real estate market, renovated and livable basement spaces are adding to the value of homes, which is another important consideration.
How can you tell the basement needs underpinning? Cracks will appear in the walls particularly ¼” wide cracks, evidence of diagonal cracks, cracks in flooring or buckled walls.
Underpinning requires specialized work that is based upon the professional opinion and consults of a structural engineer as well as the requisite building permits.
Starting from the corners and working inwards, small sections of the foundation below the footing are removed to a pre-determined depth to access the underground of an existing foundation. Load-bearing joists are placed. Alternate strips are excavated and shuttered, reinforced concrete – typically one part cement, three parts sand and six parts aggregate, is poured into each pit beneath the exposed sections of the foundation.
After about two days when the new foundation becomes completely cured, underpinning continues in the balance of the area. A new floor is laid when all is determined to be stable and the interior can then be built out.
Underpinning can take form in different processes based on various issues with the building foundation, or need to give more height to the basement. These include: screw piles and brackets, pile and beam, and underpinning using piled raft.
Underpinning your basement, foundation, and home is a costly and specialized project. You need to carefully consider all the information regarding your intentions and the issues of your home. Choose to do this specialized work with certified professionals. Whether the issue is structural or functional, the outcome will add value to your home.
