Subsidence Repair
Subsidence repair starts with understanding why a building is moving. Cracks, sloping floors, sticking doors and movement around bay windows or extensions can all point to foundation movement, but the correct repair depends on the cause.
What is subsidence?
Subsidence is downward movement of the ground beneath a building. When the ground moves, shrinks, washes away or fails to support the structure properly, part of the building can drop or rotate, causing cracking and distortion.
Common signs of subsidence
- Diagonal cracking, especially around doors and windows
- Cracks that are wider at the top or continue through brickwork
- Doors or windows sticking where the frame has distorted
- Gaps opening between walls, ceilings, skirting boards or frames
- Movement around bay windows, extensions or older additions
- Cracks that continue to reopen after cosmetic repair
Common causes
Subsidence can be caused by clay shrinkage, trees and vegetation, leaking drains, made ground, soft ground, poor original foundations, nearby excavations or changes in moisture levels below the property.
How subsidence is repaired
The repair method depends on the cause and the structure. Some issues may need drainage repairs, tree management or monitoring. More serious foundation movement may require underpinning, piled underpinning, screw piles, reinforced beams or localised foundation reconstruction.
| Problem | Possible repair approach |
|---|---|
| Bay window or extension movement | Localised piled underpinning, reinforced cages or concrete foundation repair. |
| Existing foundations too shallow | Traditional underpinning or piled underpinning, subject to excavation depth and design. |
| Restricted access or vibration-sensitive work | Screw pile or mini-piled underpinning may be considered where suitable. |
| Ongoing structural movement | Engineer-led investigation, monitoring and designed underpinning works. |
What happens next?
Send us photos, reports, trial hole information and the site address. We can then review whether the project is likely to need traditional underpinning, driven piled underpinning, screw pile underpinning or another form of foundation repair.