Underpinning & Piling to Remedy Subsidence
Subsidence is one of the significant structural issues that can affect homes. Subsidence is where parts of the house foundation move or sink leading to cracks and sticking windows or doors. The causes of subsidence can be any of the following...
- the house foundations haven't been dug deep enough;
- where clay soil contracts (due to the water table falling or due to tree roots);
- where water leakage washes soil away from the foundations.
For severe cases of subsidence, underpinning or piling is necessary to resolve the problem. This is a lengthy, dear and disruptive process. Basically, underpinning and piling is building a new foundation underneath the existing foundation so as to offer a stronger and more stable base. This will usually involve putting a metal 'table ' under the existing foundations and supporting that table with deep metal piles. If your subsidence Problems require underpinning or piling then you need to use an expert contractor to do the work.
Piling and underpinning is really specialist work. Specialists are required to analyse the subsidence and its causes in order to design a correct solution. The solution design will require complex calculations based upon the house structure, the soil, the vicinity of trees and plenty of other factors. From this there'll be a design for the underpinning table and the piles. Clearly, digging deep piles and putting a metal table underneath a home is a complicated and long task (especially if the house is close to or adjoined to other homes).
Luckily , the NHBC Buildmark warranty covers subsidence in new homes for up to 10 years after construction. Subsidence is also covered in most standard building insurance policies.
If you have severe subsidence then it is necessary to employ a contractor that has got substantial experience in resolving such issues and in undertaking underpinning projects. Such a contractor would work with structural engineers to analyse the reasons for subsidence and then with the piling experts who will design the optimum answer which is implemented by groundworks contractors. A good contractor must be acutely aware of the impact this work has on homeowners (and possibly their neighbors) and should work to achieve a top-notch solution while reducing disruption.
- the house foundations haven't been dug deep enough;
- where clay soil contracts (due to the water table falling or due to tree roots);
- where water leakage washes soil away from the foundations.
For severe cases of subsidence, underpinning or piling is necessary to resolve the problem. This is a lengthy, dear and disruptive process. Basically, underpinning and piling is building a new foundation underneath the existing foundation so as to offer a stronger and more stable base. This will usually involve putting a metal 'table ' under the existing foundations and supporting that table with deep metal piles. If your subsidence Problems require underpinning or piling then you need to use an expert contractor to do the work.
Piling and underpinning is really specialist work. Specialists are required to analyse the subsidence and its causes in order to design a correct solution. The solution design will require complex calculations based upon the house structure, the soil, the vicinity of trees and plenty of other factors. From this there'll be a design for the underpinning table and the piles. Clearly, digging deep piles and putting a metal table underneath a home is a complicated and long task (especially if the house is close to or adjoined to other homes).
Luckily , the NHBC Buildmark warranty covers subsidence in new homes for up to 10 years after construction. Subsidence is also covered in most standard building insurance policies.
If you have severe subsidence then it is necessary to employ a contractor that has got substantial experience in resolving such issues and in undertaking underpinning projects. Such a contractor would work with structural engineers to analyse the reasons for subsidence and then with the piling experts who will design the optimum answer which is implemented by groundworks contractors. A good contractor must be acutely aware of the impact this work has on homeowners (and possibly their neighbors) and should work to achieve a top-notch solution while reducing disruption.
About the Author:
SIS Construction is a family owned and run builder in Hungerford, near Newbury in West Berkshire. They have frequently been retained to do underpinning and piling work by NHBC and by other insurance companies. They have also been directly engaged by major contractors to conduct underpinning and piling work on their behalf.