House Sinking? Here Is What to Do

Signs your house may be sinking

Possible signs of subsidence or sinking include diagonal cracks wider than 3mm (especially near doors and windows, visible inside and out), doors and windows sticking, sloping or uneven floors, and rippling wallpaper. Not every crack means subsidence — much cracking is harmless settlement — but a pattern of widening, diagonal cracks with sticking doors warrants investigation (see spotting subsidence cracks).

Don’t panic — get a report

A sinking house feels alarming, but the first step is calm investigation, not panic. Commission a structural engineer’s report, which diagnoses the cause (commonly clay shrinkage, trees, or leaking drains), confirms whether movement is active or historic and stable, and recommends any remediation. Much "sinking" turns out to be old, stable movement that needs monitoring rather than major works. The report is the key document for both fixing and selling.

Notify your insurer

Subsidence is usually covered by buildings insurance, so notify your insurer early — they may handle the investigation and repair (often underpinning if needed).

Repair or sell

Once you know the cause and severity, decide whether to repair (the insurer may fund this; underpinning is the major case — see selling an underpinned house) or sell. Repairing and documenting the work gives the widest buyer market afterwards. Selling as-is is faster but at a lower price. The right choice depends on the severity, the insurance position, and how quickly you need to move.

Selling a sinking house

You can sell a house with subsidence. With a structural engineer’s report you can sell on the open market (historic, stable subsidence is often still mortgageable) or, where movement is active, the works are costly, or you need speed, sell as-is to a cash buyer who prices the remediation in and completes in 7-28 days. You must disclose the subsidence. See selling with subsidence.