Outside Tap Not Working? Causes and How to Fix It

If your outside tap isn't working, check the valve indoors before anything else. Most outside taps are fed by a pipe with its own isolation valve inside the house, and that valve is often turned off for winter and forgotten. If it's open and you still get nothing, the tap or pipe may be frozen, the washer may be stuck, or the check valve that protects the mains may have jammed. Work through the six causes below in order. The first two are free to fix, and the last one is the one that can cause damage.

1. The inside valve is off

Follow the pipe from the back of the outside tap to where it goes through the wall. Inside, that pipe usually runs to a branch off the cold main with a small valve on it. Common places are under the kitchen sink, in a utility room, in a garage or near the main stopcock.

• Lever valve: the lever should sit in line with the pipe when open.
• Screw-slot valve: the slot should run along the pipe when open. Turn it with a flat-head screwdriver.
• Small stop tap with a handle: turn anticlockwise to open.

Open it, then try the outside tap. Some newer outside taps have a built-in isolator and a drain point, so there may be a second small valve on the pipe close to where it enters the wall.

2. The tap or pipe is frozen

Outside taps are the first thing to freeze in a cold snap because the tap body and the last bit of pipe sit outside the insulated wall. If the tap worked in autumn, the indoor valve is open and it's been below freezing, ice is the likely cause.

1. Open the outside tap so melting water has somewhere to go.
2. Wrap the tap and the exposed pipe in cloths soaked in warm water, or use a hairdryer on a low setting. Start at the tap and work back towards the wall.
3. Never use a blowtorch, a heat gun or boiling water. They can split the pipe or melt soldered joints.
4. Once water flows, check the tap body and pipe for splits. Ice expanding inside a tap can crack it, and the leak only shows when it thaws.

If the pipe froze further back inside the wall or under a floor, see our guide to frozen pipes, and our tips on stopping pipes freezing for next winter.

3. Stuck washer or jammed headgear

Traditional outside taps use a rubber washer on a jumper. If the tap has been left shut for months, the washer can stick to the brass seat, so the handle turns but the washer doesn't lift and no water comes through. Limescale around the spindle can also jam the headgear.

To check, isolate the tap from inside, open it, and unscrew the headgear with a spanner while holding the tap body still. If the washer has stayed stuck on the seat, lift it off, clean the seat and fit a new washer. If the headgear itself is seized or the spindle spins freely, replace the headgear or the tap. The steps are the same as for fixing a dripping tap indoors.

4. Stuck check valve

An outside tap that could have a hose attached must not let garden water flow back into the drinking water supply. Under the Water Supply (Water Fittings) Regulations, that means backflow protection, which on a domestic garden tap is normally a double check valve. It may be built into the tap, fitted on the pipe indoors, or both.

Check valves contain small spring-loaded seals. Grit or scale can jam them shut, especially after work on the water main or after years of little use. If the indoor valve is open, the tap isn't frozen and the headgear is fine, a stuck check valve is the likely cause. It's a cheap part, but it sits in the supply line, so it needs isolating and replacing properly. Never remove a check valve and leave it out, because that removes the backflow protection.

5. Low pressure or a trickle

If the tap gives a weak flow rather than none, work through these:

• The indoor valve is only partly open. Open it fully.
• A hose connector, hose-end sprayer or timer is restricting flow. Test with nothing attached.
• The washer is worn and partly lifting, or scale is narrowing the tap.
• The whole house has low pressure. Check the kitchen cold tap. If that's weak too, see our guide to low water pressure, and check Thames Water's service updates for work in your street.

6. It's leaking instead

A tap that drips from the spout when shut needs a new washer or headgear. Water coming from around the spindle when the tap is open usually needs the gland nut tightening or new gland packing. Water running down the wall, a damp patch inside behind the tap, or a wet cupboard under the sink means the supply pipe or a joint is leaking. That one matters, because it's under mains pressure and can soak into brickwork or a floor void unseen. Close the indoor valve and have it repaired. If you can't find the source, our water leak detection guide explains the next steps.

When to call a plumber

Call a plumber if you can't find an isolation valve, the valve is seized, the tap body or pipe has split, the check valve needs replacing, or there's any sign of water inside the wall. We carry out outside tap repairs across London, from new washers and check valves to replacing a frost-damaged tap, and we can fit a proper isolation valve and drain point at the same time. If you're starting from scratch or moving the tap, see our outside tap installation service.

When you call, tell us what the tap is doing, where the pipe comes through the wall and whether you've seen any damp. Our labour is £95 an hour, the £60 call-out is waived when the job runs over 2 hours, and we confirm the price before any work starts.

Frequently Asked Questions