When to Call a Plumber for a Leaking Tap

A Drip That Costs More Than You Think

There's a particular sound that haunts a quiet house at two in the morning: the steady tick of a tap that never quite shuts off. Most of us live with it for weeks, telling ourselves it's a small thing. But a tap dripping once a second wastes around 15 litres of water a day — comfortably over 5,000 litres a year. On a water meter, that's money leaving your home one drop at a time. In a hard water area, that same drip is quietly grinding away at the inside of the tap fitting.

As a family-run plumbing and heating firm, we spend a good part of our week on jobs like these. Some take ten minutes and a couple of pounds of parts. Others turn out to be the first warning sign of something failing under the sink or inside the wall. Knowing which one you're dealing with saves you time, money and a fair bit of swearing.

What a Leaking Tap Is Usually Telling You

Almost every dripping tap comes down to one of a handful of causes, and the type of tap you have narrows it down quickly:

• A worn washer on a traditional screw-down tap. This is the classic culprit, especially on older kitchen and bathroom taps. Washers harden with age and heat, and stop sealing properly.
• A pitted or scored valve seat. The washer sits against a metal seat inside the tap body. If that seat is rough or limescaled, a brand new washer will fail within weeks.
• A failed ceramic cartridge in a quarter-turn or mixer tap. These don't have washers to replace; the whole cartridge needs swapping, and it needs the right one.
• Worn O-rings and body seals, which usually show up as water around the base of the tap rather than at the spout.
• Corrosion or a hairline crack in the tap body itself, more common than people expect in hard water areas and on cheap taps.
• Excessive water pressure, which forces water past seals that would otherwise hold. If taps all over the house drip, this is worth checking.

Where the water appears matters enormously. Water at the spout points to a washer or cartridge. Water at the base of the tap, or pooling on the worktop, points to seals or the body — and that water is going somewhere, usually into your cabinet.

Signs You Can Probably Sort It Yourself

We're always happy to be honest: some dripping taps are a straightforward DIY job, and we'd rather tell you that than take your money.

• The tap drips from the spout only, with no sign of water around the base or under the sink.
• You can isolate the tap — either a service valve on the pipe below, or by closing the stopcock.
• The headworks come apart without a fight, and the handle turns freely.
• It's a traditional screw-down tap and you have the correct replacement washer to hand.

If all four apply, turn off the water, open the tap to drain it, and take your time. Don't overtighten when you reassemble — a washer crushed too hard will fail sooner, and you can crack the ceramic seat of a mixer tap by forcing it.

When to Stop and Call a Plumber

Put the spanner down and pick up the phone if any of these sound familiar:

• Water appears at the base of the tap, on the worktop or in the cabinet below. That's a seal or body failure, and it can rot a cabinet base or lift flooring surprisingly fast.
• The drip continues after you've fitted a new washer. The valve seat almost certainly needs re-cutting or the tap needs replacing. Re-seating is a job for proper tools.
• The handle is stiff, grinding or spins without resistance. Forcing it will snap the spindle or shear the headworks.
• Nuts are rounded, seized or corroded. This is where a small job becomes an emergency, often with water spraying across the kitchen.
• It's a mixer or ceramic cartridge tap and you're not certain which cartridge you need. There are hundreds, and the wrong one will leak immediately.
• Flow has dropped on one tap only, which can point to debris or a failing flexi hose connection — sometimes the hose itself is the leak waiting to happen.

An experienced plumber will also look at what the dripping tap has been hiding. We routinely find perished flexi hoses, a slow weep on a compression joint, or a waste trap that's been quietly leaking for months.

Red Flags That Need Same-Day Attention

Some leaks aren't really about the tap at all, and they shouldn't wait until the weekend:

• Water running constantly from an overflow pipe outside, which usually means a faulty float valve in a cold water tank or a passing pressure relief valve on an unvented cylinder.
• A damp patch spreading on a ceiling, or skirting boards that feel soft near a kitchen or bathroom wall.
• Water near sockets, under-floor heating manifolds or any electrical connection.
• The pressure gauge on your boiler dropping repeatedly, or water discharging from the boiler's relief pipe.
• A sudden jump in your metered water bill with no change in habits.

These point to pipework or system problems rather than a worn washer, and they can cause real damage to ceilings, joists and electrics. Get them looked at the same day.

What Happens When a Plumber Arrives

The visit itself is usually straightforward. We isolate the supply, strip the tap down and inspect the washer, seat and cartridge. If it's a simple washer, it's often replaced on the spot and the seat checked for scoring. If the tap body is cracked or the seat is beyond saving, we'll talk you through replacing the tap rather than throwing parts at a losing battle.

While we're there, it's worth asking us to check the other taps, the flexi hoses and the isolation valves. A ten-minute look under the sink now is far cheaper than a flooded cabinet later.

To keep drips at bay: never force a tap shut, deal with a slow drip before it becomes a steady one, descale regularly if you live in a hard water area, and exercise your stopcock every few months so it actually turns when you need it. Small habits, but they're the reason some taps last twenty years and others don't see out five.