Subsidence: What It Is and How to Fix It

Subsidence occurs when the subsoil that your house sits upon pulls away from the house's foundations. This movement creates a cavity which the building then sinks into. If you're concerned that your home may be subsiding, then chances are you have seen signs that worry you. Read on for a list of the top telltale signs of subsidence and what to do if you've got them.

Signs of Subsidence

Substantial cracks in the interior and exterior walls and brickwork of your property are an obvious sign that the house has moved. Newly plastered walls can develop cracks that have nothing to do with subsidence. They are simply due to the plasterwork shrinking. Small cracks that get bigger are something to be concerned about, as these indicate movement. Cracks can appear anywhere, but in subsiding houses, they are most likely to be found around doors and window frames.

Window and door frames that have pulled away from the wall usually indicate that the house has moved. Initially, these may be very small and unnoticeable and not always a worry. Noticeable separation should be investigated.

Windows and doors may stick due to the warping of frames that are moving with the house. Sticky doors and windows do not necessarily mean that the house is sinking. However, when added to other signs, they are a good indicator that you shouldn't ignore.

Cracks in wall tiles can occur due to wear and damage. However, they can also be a sign that the wall behind the tiles is moving.

Cracked floor tiles can occur when the floor sinks unevenly. The uneven levels may not be noticeable to you. However, in serious cases, you will be able to tell that one side of a room is lower than the other.

In cases of serious subsidence, you may be able to stand away from your house and see that it is leaning to one side.

You've Spotted the Signs of Subsidence — What Now?

When you spot these signs, it's time to act as a matter of urgency. Your first point of contact will be a chartered surveyor. They will carry out an inspection to tell how serious the problem is as well as identifying the cause. Sometimes, subsidence can be remedied by repairing faulty drains or removing trees with roots under your house that are damaging the ground. In more severe cases, your home may need to be underpinned.

House underpinning is a method used to restore the integrity of your house when the foundations are failing. It involves jacking up your house with specially designed mechanical jacks and repairing the foundation by placing concrete underneath the foundation and/or around it. The underpinning will stabilise the soil that your house sits on as well as returning walls and floors to their original position. Following the process, wall and floor damage will need to be repaired Underpinning can be a substantial expense, but in many cases it will be covered by your insurance.