The drip starts at the valve, not the head
When you turn a shower off, the valve behind the handle is supposed to seal completely. If a cartridge, rubber washer or set of seats inside it has worn, a thin stream of water keeps slipping through and runs out of the lowest opening, which is the tub spout or the shower head.
A few drips right after you shut the water off are normal: that is just water draining out of the shower arm and head. A drip that is still going an hour later, or that leaves a ring of mineral stain on the tub under the spout, is the valve letting water by.
Which part is usually worn
| Handle style | Part that usually fails | Typical sign |
|---|---|---|
| Single lever or knob, one handle | Cartridge and its O-rings | Drip plus a handle that feels stiff or gritty |
| Two handles, hot and cold | Stem washer or seat on one side | Drip that is only warm or only cold |
| Three handles with a diverter in the middle | Stem washers and seats, sometimes the diverter | Drip from the spout and a diverter that won't fully switch |
| Newer single handle with separate volume and temperature | Thermostatic or volume cartridge | Drip or temperature creep after years of hard water |
Narrow it down before calling anyone
- Feel the drip.Let it fall on your hand. Warm water points to the hot side of the valve, cold to the cold side. On a single-handle valve the cartridge handles both.
- Find the stops.Many valves have small screw stops on each side, behind the trim. Some don't. If yours does, a plumber can isolate the shower without shutting the house off.
- Shut off and confirm.Close the stops or the main. If the drip stops within a few minutes, you have confirmed the water is coming through the valve.
- Photograph the trim.Take clear photos of the handle, the trim plate and any brand name on it. That is often enough for a plumber to guess which cartridge or stem fits.
Repair the valve or replace it
Rebuild in place
- New cartridge, stems, washers or seats through the trim opening
- Tile and wall stay closed in most cases
- Depends on finding a part that matches the exact valve
- Old trim can usually go back on
Replace the valve body
- Needed when parts no longer exist or the body is cracked or corroded
- Means opening the wall from the tile side or through an access panel
- Lets you move to a modern anti-scald valve
- New trim, and often some tile or drywall repair afterward
What drives the cost of a drip repair
- Whether the valve brand and model can be identified
- Whether replacement cartridges or stems are still made for it
- Whether the old cartridge comes out cleanly or is seized with scale
- Whether the valve stops work, or the whole house has to be shut off
- Whether the valve body itself is damaged and has to be replaced
What to ask a plumber
- Can you identify the valve from my photos, and is the part available?
- If the cartridge is seized, what happens next and how will that change the price?
- Will you clean the valve body and seats, or only swap the cartridge?
- What is your CSLB license number, so I can check it at cslb.ca.gov?
Common questions
Is a dripping shower an emergency?
Usually not. It wastes water and adds mineral staining, but it isn't flooding anything. If water is also showing up behind the wall or on a ceiling, treat that as a separate, more urgent problem.
Will a new shower head stop the drip?
No. The head only shows where the water comes out. The drip comes from water passing through the valve, so the valve parts are what need attention.
Why does it drip from the tub spout instead of the head?
Water takes the lowest, easiest path out. On a tub-shower combination that is the spout, so a leaking valve usually drips there first.
General information for Fullerton, not a quote or professional advice. In an emergency, call 911.