Internal drains are the waste pipes inside the house. They run from sinks, baths, showers and toilets to the point where they leave the building. Hair, grease, soap and wipes build up in them, and hidden bends make blocks hard to find.
Count the affected fixtures first to find where the block sits. One slow sink means a block in its own pipe. Several slow fixtures mean a shared pipe or an outside run, so look at the external drain unblocking guide too.
A washing machine that will not drain can also point to a block. The drain unblocking page explains the usual tools, since the same methods apply. Ask for help if a plunger does not shift it.
The engineer checks which fixtures are slow to show whether the block is local or shared. A shared block affects several fixtures at once. One slow fixture suggests a local block.
Rods, a powered snake or a small jet clear the pipe, and the trap under a fixture may come off for cleaning. The tool depends on the pipe size and the block. The right tool depends on the size of the pipe.
Running water from several fixtures at once shows whether a second block remains. This matters, since a partial block may hide behind the first. Flushing also tests the joints for leaks.
The engineer refits any traps or panels and wipes the area. Ask them to check each joint for leaks before they go. Check each fixture drains well before the visit ends. Report any new smell or damp straight away.
Use these questions to compare quotes, since the answers differ from one engineer to the next. Write the answers down, since a written note helps if the job changes. Then compare two quotes if the job looks large.
These are typical UK ranges from national price guides, not Essex quotes. Precise Drainage Solutions lists minor blocks at £80 to £150 and moderate ones at £150 to £300. MyJobQuote lists rodding at £80 to £145.
Complex or recurring blocks can cost £300 or more, according to Precise Drainage Solutions. Ask for a written quote before work starts, and ask whether there is a call-out charge, because policies differ. Quotes vary, so compare two if you can.
More than one slow fixture usually means a shared pipe or an outside run is blocked. Individual traps rarely fail together, since each has its own pipe. Check the outside gully as well.
It can. A block may make water leak from a joint or overflow from a trap when the water has nowhere to go. Long-term leaks can damage plaster and floors, so act early. Ask the engineer to check the joints too.
Usually not. Engineers reach internal drains through traps, clean-out plugs and outside chambers. Ask before the work starts, since some pipes have poor access. Ask whether any lifting is likely.