Blocked Sink London — Kitchen & Bathroom Unblocking

Slow kitchen sink drainage in London is almost always grease accumulation. Cooking fats seem liquid when they go down the drain but solidify on the cooler pipe walls as they move away from the sink. London's hard water compounds the problem — scale deposits on the inner pipe wall create a rough surface that grease clings to. Over months and years, the effective pipe bore narrows significantly. Regular boiling water flushes slow the build-up, but once the sink drains slowly, mechanical clearance or jetting is needed.

A standard kitchen sink unblocking costs £95–£130 using a mechanical snake or rods, including trap inspection and a flow test. For more stubborn grease blockages in long waste runs, we may need to jet the waste pipe (£150–£200). Full drain runs from kitchen to external drain cost £200–£300 for jetting clearance. We quote before starting and don't add surprise charges.

For a fresh soft blockage — yes. A plunger, followed by boiling water if the pipes are metal/ceramic (not plastic), resolves many bathroom basin blockages. Chemical drain cleaners work on hair/soap build-up in bathroom sinks but are less effective on kitchen grease — the caustic dissolves some grease but rarely fully clears an established kitchen blockage. For a kitchen that drains slowly despite these measures, or one that's completely blocked, call us. Repeated chemical treatment can damage plastic waste fittings.

The P-trap (or bottle trap in UK bathrooms) is the U-shaped pipe under the sink that holds water to prevent drain smells. It also catches debris. In kitchen sinks, grease accumulates in the trap and the downstream pipe. In bathroom basins, hair and soap form a plug in the trap, often around the pop-up waste mechanism. Both are cleared by removing the trap body (place a bucket under it first) and cleaning it out, or by using a snake through the waste.

A drain smell from a properly draining bathroom sink usually indicates the trap water seal has evaporated (from a sink not used for weeks) — simply run the tap for 30 seconds. If the smell persists with regular use, the issue is usually decomposing organic material in the overflow (the small hole just below the tap) — the overflow path is rarely cleaned and accumulates hair, soap and bacteria. An enzyme-based drain cleaner poured into the overflow resolves this. If the smell is sewage-like, the issue may be a faulty waste pipe connection — call us.

If the blockage is in a shared drain serving your building (accessed from outside or in a communal area), it's typically the building owner/freeholder's responsibility (or Thames Water if it's in the public sewer). If the blockage is in your individual waste run — from your sink to the point where it joins the shared drain — it's your responsibility as the flat occupier. We can help identify the blockage location with a CCTV inspection if it's unclear.

Three effective measures: (1) Never pour cooking fat or oil down the drain — let it cool in a container and dispose in the bin or oil recycling point. (2) Use a sink strainer to catch food debris. (3) Monthly treatment with a hot water flush (boiling water directly down the drain, not through the kettle spout into the sink) or an enzyme-based drain cleaner. In London's hard water, a limescale descaler quarterly also helps maintain pipe bore in plastic waste fittings.

Yes. If the waste pipe runs under the floor or behind a wall, we access it via the cleanout points at the stack or gully, or with a long snake from the sink end. If there's no cleanout and the pipe needs jetting, we may need to create an access point — but this is rarely needed for domestic sink waste runs. We assess before starting and explain options if access is limited.

A blocked sink job typically means clearing the waste pipe from the sink to the external drain or soil stack — usually 2–5 metres at most. Drain jetting refers to jetting the external drain run (underground pipework from the soil stack to the sewer main). We carry equipment for both: a small-bore mechanical snake for kitchen/bathroom waste pipes and a full high-pressure jetting rig for external drain runs. A blocked sink call may reveal that the blockage is actually in the external drain, in which case we upgrade to drain jetting on the same visit.

Re-blocking within days or weeks usually means the original clearance was partial — the blockage was disturbed but not fully removed. In kitchen sinks, a grease mass broken up with rods often reforms downstream. We recommend jetting after rodding for London kitchen drains — jetting removes the grease from the pipe walls rather than just pushing the mass further down. If the drain re-blocks after jetting, a structural issue (offset joint, partial pipe collapse) is creating a debris trap — a CCTV survey will show this.