Problem guide · Blocked sink
A single slow sink often points to the trap or nearby waste pipe. Several slow fixtures, gurgling toilets or an overflowing outside gully indicate the issue may be farther down the drainage system. The distinction matters because cleaning a trap will not clear a shared external restriction.
Diagnosis before equipment
The page answers the question directly, then shows how the decision changes with symptoms, access and evidence.
Kitchen waste commonly carries fats, oils, food particles and detergent residue that cool and collect in the pipe. Bathroom basins more often accumulate hair, soap and cosmetic residues.
A completely sudden blockage may involve a solid item or a restriction downstream rather than gradual surface build-up.
Remove visible debris from the plug area and check whether another nearby fixture is slow. A removable trap can sometimes be cleaned by someone competent, with the water isolated and a container below.
Do not mix chemical cleaners or dismantle a trap containing chemicals. Stop using the sink if water is appearing in another fixture or outside.
Restrictions beyond the accessible trap may need mechanical cleaning or jetting from a suitable access point. The method depends on the waste pipe and where it joins the drainage system.
Repeated kitchen blockages can indicate significant grease coating, poor flow or a design issue that needs more than a one-off plunge.
A clear route through the problem
No mystery journey and no jumping straight to the most expensive option.
We establish whether the fault is local or shared.
The safest useful access point is selected.
Cleaning matches the pipe and material.
Normal discharge is checked after clearance.
Straight answers
Very hot water can damage or deform some plastic pipework and will not solve every obstruction. It is safer to identify the material and cause first.
That suggests the restriction is at or beyond the gully rather than only in the sink trap.
They can cause burns, react with other products and create a hazard during dismantling or professional clearance. Never mix them.
Possible causes include trapped residue, a dry or faulty trap, poor venting, an external blockage or a leak. The pattern and location need checking.
Local knowledge
Older terraced streets, shared runs and sudden downpours shape most of what goes wrong with drainage here.
Much of the town's housing was built long before modern drainage standards. Terraces frequently share one private run between several homes, and older clayware has joints that shift, shallow falls and cracks that tree roots can find. Once grease, silt and wipes accumulate in a pipe that has already narrowed, the blockage arrives long before the pipe is completely full.
Broadly speaking, the pipework that serves your property up to the point where it connects to the public sewer sits with the property owner. Public sewers in this area are the responsibility of United Utilities. Shared runs can make that split less obvious, so it is worth confirming the layout rather than assuming who will attend.
A run that re-blocks repeatedly usually points to something a clearance cannot remove: root ingress, a displaced joint, a dropped section, hardened silt or a fall too shallow to carry solids away. A second clearance buys time, but camera evidence on the suspect section is what shows whether a repair or lining is the real answer.
Problems appearing on adjoining properties at the same moment usually indicate a shared drain or a restriction further downstream rather than a fault inside either home. Clearing only your own section will not restore the flow, so mention it when you book so the visit is planned around the shared run.
A smell without a blockage is usually about seals and ventilation rather than flow: a dry trap in a rarely used sink or shower, a damaged gully cover, a pan that has shifted or a cracked section letting odour rise. It is worth investigating, because the same defect can let water escape unnoticed.
They can. Many local streets use combined systems that carry both rainwater and foul water, so a sudden downpour can fill the pipe faster than it drains and water appears at gullies and low chambers. If levels fall once the rain stops that is usually capacity; if water stays high or sewage appears, treat it as a blockage and call.
