Drain excavation means digging down to a damaged pipe and replacing it. It suits a pipe that has collapsed or shifted badly. In those cases a liner cannot do the job, since it needs a pipe that still holds its shape.
A camera survey should come first. It shows the position and depth of the fault, so the dig can be short and neat. However, without it the trench may be longer than it needs to be.
Read about pipe relining and patch lining to compare the no-dig options, since a liner may suit your pipe. The wider guide to drain repairs sets out every route. Choose after you see the survey footage.
Drainage work in Scotland falls under Standard 3.7 of the Building Standards Technical Handbook, which covers wastewater drainage. Ask the engineer whether your job needs any sign-off under those rules, and check the current edition of the handbook, since editions change.
If the dig crosses a neighbour's land or a public footpath, ask who arranges permission. However, if the pipe is a public sewer, Scottish Water is responsible for it, so ask Scottish Water before you pay for work. Get the answer in writing.
A camera survey and a tracing tool show where the fault sits. The dig then starts at the right spot. This keeps the trench as short as it can be, although depth still sets the limit.
The job starts by removing the surface and opening the ground to the pipe. Take care near other services, for example cables and water pipes. Ask how the team will find and avoid them.
The damaged section comes out and a new pipe goes in. The new pipe needs sealed joints and a steady fall so water drains. A test run before closing is usual, since a fault costs less to fix while the trench stays open.
Filling the trench in layers comes next. Restoring the surface with turf, paving or concrete comes last. Ask exactly what the quote covers here, since surface work can cost a lot.
The engineer who takes your job runs a separate business, so the engineer sets the price, the arrival time and any guarantee. Use these questions to compare quotes, since answers differ from one engineer to the next. Write the answers down, because a written note helps if the job changes.
Fantastic Services says a serious blockage that needs excavation starts at around £600. Book A Builder gives £1,000 to £5,000 or more for excavation and replacement, over one to five days. These are UK guide ranges, not Dundee quotes, so real prices may still differ.
Depth, length and the surface above the pipe change the price. Ask for a written quote that names the length of pipe and the surface work. Compare two quotes, since repair prices vary widely.
Book A Builder gives one to five days for excavation and replacement. A short, shallow dig is quicker than a long or deep one, although access also matters. Ask the engineer for an estimate before work starts.
A dig opens the ground, so some disturbance is certain. A neat trench based on survey data keeps it small. Ask what the quote covers for restoring turf, paving or concrete, since this part of the price differs a lot.
Often yes, because a pipe that has collapsed or lost its shape usually cannot take a liner. A camera survey shows which repair fits. Ask to see the footage before you agree.
The owner of the pipe pays. You pay for a drain that serves only your property. However, a pipe that serves several properties is usually a sewer, so ask Scottish Water first.