Repeat blockages in the same place
The clearest sign. Broken pipe leaves a rough edge or a step inside the run, and waste catches on it every time. If the same section blocks two or three times a year, the pipe, not the household, is the problem.
Slow drainage across several appliances
When a sink, a bath and a toilet all drain slowly, the restriction is in the shared run rather than in any one trap. A partial collapse reduces the bore and does exactly this.
Sinking ground, cracked slabs or subsidence
Water escaping from a broken pipe washes fine material out of the surrounding ground. The surface above then settles. A dip in a lawn, a sunken paving slab, a driveway that has dropped along a line, or new cracking in a wall near the drain line all deserve investigation.
Damp and unexplained smells
A broken drain under or beside a building can push damp into a wall or floor and let foul gas escape. If damp keeps returning after treatment and the drain line runs nearby, check the drain before you spend more on the wall.
Rats
Rats live in sewers and get into gardens and buildings through defective drains. Fresh rat activity around a property with a history of drainage trouble is a strong hint that there is an opening in the pipework.
Confirming it
None of these signs prove a collapse on their own. A CCTV survey does. The camera shows whether the pipe is cracked, displaced, deformed or fully collapsed, and gives the distance and depth so the repair can be planned precisely rather than dug for speculatively.
Repair options once it is confirmed
- Patch lining for a short defect in an otherwise sound pipe, with no excavation.
- Full relining where a longer section is cracked or has open joints.
- Excavation and replacement where the pipe has fully collapsed and there is nothing left to line.
- Drain milling to remove intruding roots, concrete or scale before lining.
Questions we get asked
Can a collapsed drain be repaired without digging?
Often, yes. If the pipe still holds its shape, a patch liner or a full liner cures inside it and restores a smooth bore. A fully collapsed section with no remaining profile has to be dug out and replaced.
Does home insurance cover a collapsed drain?
Many buildings policies include cover for underground services, subject to the terms. Insurers normally want CCTV evidence, and we supply footage and a written report suited to a claim.
How quickly does a collapse get worse?
It varies. A crack can stay stable for years or fail in a season, particularly under a driveway carrying vehicle loads. Once it is confirmed, it is better dealt with while it is still linable.