Drain repair and relining

A cracked or broken drain rarely announces itself until something goes wrong: a blockage that keeps coming back, a smell, damp in a basement wall, a sinking patch of path or rats. In the period houses we work in, drains are often old clay pipes laid well over a century ago, under gardens, paths and basements, with mature trees close by. When a CCTV drain survey shows damage, there are three main ways to put it right.

Patch repair

For a single crack, a broken joint or one point where roots get in, a patch repair seals just the damaged length. A short sleeve of resin-soaked liner is carried into the pipe on an inflatable packer, pressed against the damaged section and left to cure. The Water UK specification for localised sewer repairs describes this kind of short-length cured-in-place patch. It is quick, and nothing is dug up.

Relining

Where damage runs along a longer length, the whole section can be relined. A flexible liner soaked in resin is inserted into the old pipe, inflated against its walls and cured into a new, jointless pipe inside the old one. The water industry uses the same cured-in-place technique on public sewers, and Water UK’s Standards Board publishes guidance on it. Relining seals cracks and joints, stops roots getting in and smooths the inside of the pipe so it is less likely to block.

Worth knowing: Relining avoids digging up gardens, drives and, in particular, basement floors and finished interiors. In a listed house or a street of conservation-area front gardens, that can make a big difference to disruption and to what permissions you need.

Excavation

Sometimes there is no way round digging. A section that has collapsed, sunk badly, been crushed or been laid at the wrong fall usually has to be exposed and replaced. We keep the excavation as small as the repair allows, protect what is around it and reinstate the ground afterwards.

Before and after

Every repair starts with a survey, so we know exactly where the damage is and which method suits it. After the repair, we run the camera through again to check the result. Where trees are involved, we also talk about the roots, because a sound pipe is the best defence against them.

Whose drain is it?

Since 1 October 2011, Thames Water has been responsible for most drains shared with other properties and for lateral drains outside your boundary. The pipe serving only your property, inside your boundary, is yours to repair. The survey shows exactly where the damage is, which usually settles the question.

To discuss a drain repair, call 07862 142953 or send us the survey and a photo on WhatsApp. If the drain is blocked right now, see drain unblocking.