What is going on
Inside every shower valve is a cartridge that blends hot and cold. Hard water wears it, scale jams it, and the anti-scald piece inside it eventually stops reacting fast enough. That is why the water goes cold when the dishwasher kicks on, or a drip will not quit after you shut it off. Weak spray is usually a scaled shower head or a stuck flow restrictor. Water showing up on a ceiling below or a baseboard outside the bathroom is a different story: that can be a valve body leak, a failed drain gasket, or a pan that has cracked.
What we check
- 01
Valve brand and cartridge
Identified from the trim so we bring the right replacement part.
- 02
Temperature behavior
We watch how the valve reacts when another fixture runs. That tells us if the balancing spool is failing.
- 03
Head and arm
Pulled and checked for scale and a cracked arm threaded into the wall.
- 04
Drain and pan
Water tested at the drain to rule out a gasket or pan leak behind the scenes.
- 05
Access panel or wall
Whether there is a way in from behind, which can save a lot of tile.
Your options
Cartridge replacement
Drip or temperature swings from a valve that is otherwise sound.
Head, arm or diverter
Weak spray, leaks at the arm, or a tub spout that will not divert.
Valve replacement
Discontinued or corroded valve body. We work through an access panel when one is possible.
Before we get there
If the shower drips nonstop, you can close the main valve overnight or use the shutoffs behind an access panel if your bathroom has one. Write down when the temperature swings happen. Toilet flush, dishwasher, washing machine: each clue helps.