Underpinning is the process of extending the building foundations to a greater depth. This can be required due to settlement or to facilitate works which would otherwise undermine the existing footings.
The process of underpinning
If a property’s foundations are not deep enough they can be underpinned to get them to a suitable depth. The soil beneath the existing footings is excavated in 1.0m or 1.2m long bays (or pins) and filled with concrete. When the concrete has cured the gap between the top of the new concrete and the underside of the original foundation is filled with a dry packed grit and cement mixture. The pins are excavated in a prearranged sequence to eliminate the chance of the property moving during the works.
Foundations are usually modified based on an engineer’s designs and require a certificate from a Building Inspector on completion. We complete all works in accordance with local authority regulations, with risk assessments and method statements supplied as required.
If your property requires underpinning or you have any concerns about foundation movement please contact us. We are happy to talk through your situation and tell you how we can help.