We carry out underpinning, subsidence repairs and related structural work in Wavertree, L15, to a chartered structural engineer’s design. Calls here split between Victorian terraces with bays and inter-war semis, and the cause is quite often a drain or a lintel rather than the foundations. Finding which it is comes first.
Terrace or semi: what the cracks tend to tell us
Wavertree, in L15 and under Liverpool City Council, has a large stock of Victorian terraces with bay windows and a good number of inter-war semi-detached houses. The two types age differently.
| Victorian bay terrace | Inter-war semi | |
|---|---|---|
| Typical crack locations | Over the bay and front windows; rear outrigger junction | Bay junction, corners, extension junctions |
| Common non-foundation causes | Old lintels, decayed timber, alterations | Corroding steel lintels, early wall ties |
| Ground-related causes to rule out | Old clay drains near the back wall | Trees, drains, shallow bay footings |
| Neighbour issues | Party walls on both sides | One party wall |
The table is a guide to what gets checked, not a diagnosis. Every property is looked at on its own merits.
Old drains behind the terraces
Many terraced rows have drains running close to the back of the house, sometimes under yards or extensions. If those pipes leak, they can soften the ground below the footings or carry fine soil away. A CCTV survey is the usual way to find out. When a drain is to blame, the fix is generally to repair it, give the ground time, and then repair the cracks. Our page on drainage-related subsidence explains that sequence.
Lintels and bay windows
Sagging brickwork or a stepped crack over a window can point to a lintel that has rusted, rotted or was never adequate. Replacing a lintel is structural work, needing temporary support and usually Building Regulations involvement. Where a bay itself has dropped, the engineer may look at its footing. See lintel replacement and our notes on bay window subsidence.
If an insurance claim is likely, contact your buildings insurer before any repair. The insurer decides on investigation and repair method, and whether underpinning is needed at all.
What the first phone call covers
We ask what you have seen and where, whether it is new, the type and rough age of the house, any trees, extensions or drain problems you know of, and whether an insurer, buyer or neighbour is involved. From there we arrange a visit and tell you plainly what we think should happen next.
Neighbouring areas
We work next door in Childwall and Old Swan, and in Mossley Hill to the south. To see the full range of subsidence and underpinning work across Liverpool, head to Underpinning Liverpool’s homepage.
Cracks in a Wavertree terrace or semi?
Give us a ring on 07777 659786. Describe the cracks and where they are, and we will call back to talk through what to check first.
Frequently asked questions
Could a leaking drain cause cracks in my Wavertree terrace?
It can. A broken or leaking drain can soften clay or wash fine soil from under a footing, and older terraces often have clay drains near the back wall. A CCTV drain survey usually shows whether there is a defect. If a drain is the cause, repairing it and letting the ground settle may be enough before the cracks are repaired.
Who is responsible for drains behind a row of terraced houses?
Since 1 October 2011, shared private sewers and lateral drains outside a property boundary transferred to the water companies in England. On Merseyside that is United Utilities. A drain inside your boundary serving only your house is still yours. Who owns a particular run can need checking, so ask before assuming.
Is a crack above my front window a foundation problem?
Often it is not. Cracks above windows and doors are frequently caused by a failing lintel, especially old steel or timber ones. They can also come from movement below. An inspection looks at the shape of the crack and the condition of the lintel. See our lintel replacement page for that side of things.
Should I fill the cracks before I sell?
Do not fill or paint over cracks to hide them, and never conceal past movement from a buyer, lender or insurer. Photograph and date the cracks instead and get a structural engineer’s view. Repairs should follow a diagnosis, not come before it.
What if cracks are opening quickly?
Keep people away from the affected area and get urgent professional advice. If a wall or ceiling looks unsafe, Liverpool City Council’s building control team can be contacted about dangerous structures. If you smell gas, leave and call the National Gas Emergency Service on 0800 111 999.