Blocked sinks, toilets and internal drains

What you might notice

One sink or basin drains slowly

We start with the waste fitting at the plughole and the trap underneath. If both are clear, we check further along the waste pipe.

Water stays in the basin

Tell us whether the plug opens and whether any water drains away. A jammed plug can hold water in the bowl. With the plug open, standing water can indicate a complete blockage.

Two fittings affect each other

A basin gurgling when an appliance drains, or water appearing in a shower when a toilet is flushed, can point to a shared branch.

A toilet backs up

Stop flushing if water is rising. Tell us whether other outlets are affected and whether there has been an overflow.

Dirty water comes back when a washing machine empties

A sink and appliance may share part of the waste pipe. Tell us where water comes back up and which appliances were running.

There is a bad smell at the basin plughole

Build-up in the waste fitting or trap can smell. A trap holds water to keep drain smells out of the room. If the basin has been unused or the smell changes when another outlet drains, mention it so we can check the water seal and connections.

Water returns through the other bowl of a double sink

If it happens when you empty the first bowl, the restriction may be after the two wastes join. Tell us whether both bowls are affected and whether an appliance uses the same waste.

Which fitting is affected?

01Kitchen sink or utility waste

We start with the trap and accessible waste pipe. Knowing whether one or both bowls drain slowly helps narrow down where the restriction may be.

02Bathroom basin with a vanity or pedestal

Tell us if the trap sits behind a drawer or pedestal. We check what can be reached and explain any access needed before starting work.

03Bath or shower drains slowly

We check the accessible waste and trap. A shower that leaks through the ceiling only while draining may need a waste repair as well as, or instead of, clearing.

04Several outlets or an outside gully back up

Tell us whether neighbours are affected or an outside gully is overflowing. A shared or public sewer may need the wastewater company, and the symptoms can help decide whom to contact.

What we can do

We check the affected outlets and accessible waste pipework. For partial or complete blockages, we discuss manual or vacuum clearance according to the fitting and access. We check the flow afterwards. A shared or external drainage fault may need the responsible party or a specialist. Clearance addresses the blockage present at the time.

Parts we may check or replace

These are examples. We check what is fitted before choosing a replacement.

McAlpine TP10 1½-inch swivel trap

The trap beneath a sink holds water to keep drain smells out of the room. If its body or seal leaks, we check the waste size and outlet direction for a replacement. If the trap is sound and the blockage is further down, clearing the pipe is a separate job.

Manufacturer details

McAlpine basin clicker waste with bottle trap

The clicker closes the plughole. The trap below keeps a water seal. We check which piece has failed and whether a compatible plug or mechanism can be fitted to the existing waste.

Manufacturer details

Before you get in touch

Tell us which fixtures are affected, when the problem started and whether drain chemicals have already been used. Avoid adding more chemicals while you wait.

• Why is water leaking from my shower tray or screen?
• Washing machine and dishwasher plumbing problems
• Is it a blocked sink or a shared drain?
• Why is there water under my kitchen sink?