Shower hose leaking —
where it comes from
and what to replace
At connection leaks, the hose body is often not the problem. The washer that seals the connection has hardened, flattened permanently or cracked. Replacing it is usually inexpensive and often takes only a few minutes.
Scope: This article covers visible water-side leaks and seal identification at external hose, tap and connector points. Do not work on a live electrical appliance, do not open sealed appliance internals, and follow the appliance manufacturer's instructions. If isolation, access or the source of the leak is unclear, use a competent plumber or appliance engineer.
Where the leak is coming from
Dry the area around the hose connections and run the shower briefly. Identify exactly where water appears — the location determines what needs replacing.
How the connection seals — and why PTFE tape does not fix it
Shower hose connections are flat face connections. The hose fitting has a flat end face. The outlet or handset port has a corresponding flat seat. A rubber washer sits between these two flat surfaces and is compressed when the fitting is hand-tightened.
The thread provides clamping force only. The washer provides the seal. When the washer degrades, the thread remains tight but the seal is gone — which is why a leaking connection that feels correctly tightened still drips.
PTFE tape on a shower hose thread does not seal the joint. PTFE tape belongs on tapered thread connections where the thread itself seals. Shower hose connections are parallel flat face joints. Tape on the thread may temporarily slow a drip but does not replace the washer, and can prevent the faces from closing correctly.
The washer — what it looks like and where it sits
Unscrew the hose fitting from the outlet or handset. Look inside the fitting end — the washer is a small flat ring sitting in a shallow recess. It may be black rubber, grey rubber or a translucent material depending on the hose brand and age.
A washer that has failed will typically look one of these ways:
- Flattened and hard: the washer has compressed permanently and lost its elasticity. It no longer springs back to fill the sealing gap when the fitting is assembled.
- Cracked or split: surface cracks, typically around the inner or outer edge, indicate the rubber has aged and become brittle.
- Missing: occasionally a washer falls out during disassembly without being noticed, and the connection is reassembled without one.
At the handset end: some shower handsets use a small O-ring rather than a flat washer at the hose connection point. If you unscrew the hose from the handset and see a round-section rubber ring in a groove rather than a flat washer in a recess, you need an O-ring replacement rather than a flat washer. The two sealing types should not be treated as interchangeable without checking the fitting design. Measure the O-ring — inside diameter and cross section — before ordering a replacement.
Washer size — what to order
Many standard UK and European shower hoses use a 1/2 inch BSP connection at both ends. The flat washer for this connection is typically:
- 18.5 × 10 × 2 mm — a commonly encountered size for standard 1/2 inch shower hose fittings
- 18.5 × 11 × 2 mm — another variant seen on some hose brands
Hose brands vary. Measuring the original washer — outer diameter, inner diameter, thickness — is more reliable than assuming a standard size fits. If the washer is too degraded to measure, measure the recess inside the fitting instead.
Sizes are indicative for common European shower hose fittings. Actual dimensions vary by manufacturer and hose series.
How to replace the washer
Turn off the water supply
Close the shower valve or isolate the supply. Have a towel ready before disconnecting.
Unscrew the leaking end
Most fittings are hand-tight. Remove the fitting from the outlet or handset whichever end is leaking.
Remove and measure the old seal
Hook out the washer or O-ring carefully. Measure it if possible, or measure the recess. Clean any rubber residue before fitting the replacement.
Fit the replacement and retest
Drop the new seal in flat. Reconnect hand-tight. Turn on the supply and check for drips under pressure.
For connection leaks, the usual failure point is the washer or O-ring inside the fitting rather than the hose body itself.
Find the exact leak point first — wall end, handset end, or hose body. For connection leaks, the flat washer or O-ring inside the fitting has failed. Replace it with the correct size. Do not attempt to seal a flat face connection with PTFE tape.
FAQ
Why is my shower hose leaking at the connection?
A common cause of a shower hose leaking at a connection point is a failed flat rubber washer inside the hose fitting. Shower hose connections — at the handset end and at the wall outlet or mixer tap end — use flat face seals. A small rubber washer sits inside the threaded fitting and is compressed between the fitting face and the mating surface when the connection is tightened. When the washer hardens, flattens permanently or cracks, the joint starts to drip. The washer is the seal, not the thread. Replacing it is usually the correct first repair when the leak is at the connection and the mating faces are undamaged.
What size washer does a shower hose use?
Many standard UK and European shower hoses use a half-inch BSP connection at both ends — at the handset and at the wall outlet or mixer tap port. A common flat washer size for this connection is around 18.5mm outer diameter, 10mm inner diameter, 2mm thick — sometimes listed as 18.5x10x2mm or as a half-inch shower hose washer. Some hose brands use slightly different dimensions, so measuring the original washer before ordering a replacement is the reliable approach.
Can I fix a shower hose leak with PTFE tape?
PTFE tape is not the correct fix for a shower hose connection leak. Shower hose fittings use flat face connections — the seal forms between two flat faces through a compressed rubber washer, not on the thread. PTFE tape belongs on tapered thread connections where the thread itself seals. Wrapping PTFE tape around a shower hose thread may temporarily slow a drip but does not address the failed washer and is not a reliable long-term fix. The correct repair is to replace the flat washer inside the fitting.