Collapsed Drain Repair Quotes: What Decides the Price

How much a collapsed drain repair costs depends on how deep the pipe is, what is on top of it, how long the damaged section is, and whether it can be lined or must be dug up and replaced. Depth and surface usually matter more than the pipe itself, which is why two collapsed drains in the same street can cost very different amounts to fix. Before any of that, it is worth checking that the collapsed pipe is actually yours to pay for.

How do you know a drain has collapsed?

You usually find out from a CCTV survey after repeated blockages, slow drainage or a dip in the ground. A collapse cannot be confirmed from the surface, so any repair price given before a camera has been down the pipe is an estimate, not a quote.

Common warning signs are a drain that blocks again soon after being cleared, water backing up in an outside chamber, a persistent smell, a sunken patch in the lawn or paving above the drain line, and rats appearing near the house. None of those proves a collapse by itself. A camera shows whether the pipe has fully collapsed, partly deformed, cracked, or simply had a joint move. That matters for cost, because a cracked or displaced section can often be lined without digging, while a pipe that has lost its shape usually cannot. If you do not have footage yet, a CCTV drain survey is the first cost to budget for.

Is the collapsed drain your responsibility?

Only if it serves your property alone and sits inside your boundary. Many collapsed pipes in London turn out to belong to the sewerage undertaker, and repairing those is not your cost.

Since October 2011, pipes that serve more than one property and connect to the public sewer, and lateral drains running beyond your boundary, have generally been the responsibility of the sewerage undertaker, which in London is Thames Water. A collapse on a shared run under your garden may therefore be theirs to fix even though it is on your land. The CCTV footage should show where the collapse is relative to junctions and your boundary. Our guide to who pays for a drain in London explains the test in more detail.

What drives the price of a collapsed drain repair?

Depth, surface, length and access. The pipe material is a small part of the bill; most of it is digging down, working safely at depth and putting the surface back.

• Depth. A drain half a metre down in a garden is a small dig. One two metres down needs the trench supported, takes longer and produces far more spoil.
• What is on top. Lawn is cheap to reinstate. Block paving, concrete, a patio laid on a slab or a kitchen floor add a lot, both to break out and to relay.
• Length of the damaged section. A single collapsed length is one repair. Several defects along a run may make replacing the whole run better value than patching each.
• Access. Terraced houses with no side access may mean every bucket of spoil goes out through the house. That is slow, and it shows up in labour time.
• Location. A collapse under a public pavement or road needs permission from the highway authority and traffic management, which adds cost and time.

Can a collapsed drain be relined instead of dug up?

Sometimes, but not when the pipe has lost its shape. Relining puts a new pipe inside the old one, and it needs a route for the liner to follow.

Where a pipe is cracked, has open joints or has a small displaced section, lining can often be done without digging, and it is usually cheaper because there is nothing to break out and relay. Where a section has fully collapsed, the liner has nothing to form around, so that section normally has to be excavated and replaced. A common approach is to dig out the collapsed section only and line the rest of the run if it has cracks. A good quote explains which parts are being dug and which are being lined, and why. Our comparison of no-dig repair versus excavation covers the choice in more detail.

Will home insurance pay for a collapsed drain?

Often, if your buildings policy covers accidental damage to underground pipes, and if the collapse was sudden rather than gradual wear. Read the policy wording before you assume either way.

Insurers usually want CCTV footage and a written report showing the defect and its likely cause, such as ground movement or root damage. Gradual deterioration and wear are commonly excluded. Keep the footage, the report and an itemised invoice that names the pipe section repaired, the method used and the length replaced. A single line reading "drain repair" gives an insurer little to work with.

How do you compare collapsed drain repair quotes?

Make sure each firm is quoting to fix the same defect, identified from the same footage. Quotes based on different surveys, or on no survey, cannot be compared fairly.

Ask each firm: which section they will repair and how long it is; whether they will dig, line, or do both; how deep the pipe is; what surface they will reinstate and to what standard; how spoil will be removed; and whether a camera check after the repair is included so you can see the finished work. Our published rate card shows how we set out labour by time band. If a quote recommends replacing a whole run when the footage shows one defect, ask why. Sometimes that is the right call, but you should be able to see the reason.

For how we carry out the repair itself, whether by lining or by digging, see our collapsed drain repair and excavation service.