Signs you need this
- Toilet hissing between flushes, or wobbling on its flange
- Drip at the spout or water under the vanity
- Shower that swings hot and cold
- Hose bib dripping or split after frost
Kit on the van, and the method
- Basin wrench and seat wrench
- Wax rings, closet bolts and flange repair rings
- Cartridges, stems and seats for common valve makers
- Toilet auger and closet plunger
Before we leave: Cycle the fixture hot and cold, check every joint dry with a paper towel.
Pressure-balance valves
Most showers installed in Ontario in recent decades use a pressure-balance valve. Inside is a spool that reacts to changes in hot or cold pressure. When a toilet fills and steals cold water, the spool cuts back hot water to match, keeping you from getting scalded. When the spool sticks from mineral build-up, the protection fails and the temperature swings.
Durham's moderately hard water is a factor. Scale builds on cartridges and spools, making handles stiff and temperature control unreliable. A new cartridge often solves it. Our note on hard water in Durham explains why it keeps coming back, and a water softener reduces the build-up.
Thermostatic valves are an alternative. They hold a set temperature regardless of pressure changes and allow separate control of volume. They cost more and suit some renovations well.
Repair or replace
- Dripping spout or head: often a worn cartridge or seats. Repairable if parts are available.
- Stiff handle: scale on the cartridge. Cleaning or replacing it usually works.
- Temperature swings: a failing pressure-balance spool. Replace the cartridge first.
- Obsolete valve with no parts: replacement of the valve body inside the wall.
- Leak inside the wall: open, find, and repair or replace.
Access panels
Replacing a valve body means reaching the back of it. The best case is a closet or bedroom wall behind the shower, where we cut a neat opening and leave a removable access panel. If the only access is through the tiled side, we work through as small an opening as possible, and the tile restoration may need another trade. We describe which side we will open before any cutting.
Trim kits
The trim is the handle, escutcheon plate and sometimes the spout and head. Manufacturers design trim to fit their own valve bodies, so a trim kit from one brand rarely fits another brand's valve. If the old valve is sound and you only want a new look, a matching trim kit from the same maker is the simplest upgrade. If the valve is being replaced anyway, you have a wider choice of finishes and styles.
We set the valve depth carefully so the trim sits flush with finished tile, then pressure the valve and watch for weeps before the wall is closed. Larger bathroom changes belong under bathroom plumbing renovation.
Before we arrive
Note the brand name on the handle or escutcheon if one is visible, and take a photo of the trim. Check whether the house has a dedicated shut-off for the bathroom. Older valves often lack built-in stops, which means the main has to be closed while the cartridge comes out. Knowing that in advance helps everyone plan the visit and keeps the rest of the house without water for the shortest possible time.
Asked on the phone
Why does my shower go hot when someone flushes?
The pressure-balance spool in your valve is likely sticking. A new cartridge usually restores it.
Can I change the shower handle without replacing the valve?
Usually, if you buy trim made for your existing valve brand and model.
Will you need to break tile?
Not when we can reach it from the far side of the wall. We check the back wall first.
