Quick answer
A shower valve controls the flow and temperature of your shower. A thermostatic valve holds a set temperature and cuts the flow if the cold supply fails, which protects against scalding, so it is the safer choice for families and hotels. A manual valve is cheaper but you balance the temperature by hand. Valves come exposed (on the wall) or concealed (built in), and complete shower systems add a riser rail and head. Grohe thermostatic options at Kent Traders start around £209.
Thermostatic vs manual
This is the main decision. A thermostatic shower valve has an internal element that keeps the water at the temperature you set, even if someone runs a tap or flushes a toilet elsewhere. Crucially, if the cold supply drops, it shuts the flow down rather than letting the water run scalding hot. That anti-scald behaviour is why thermostatic valves are recommended for homes with children or elderly users, and standard in hotels and commercial washrooms.
A manual (single or dual control) valve simply mixes hot and cold in the proportion you set. It costs less, but the temperature can swing if water is drawn off elsewhere, and it offers no scald protection. For a low-use ensuite on a stable supply it can be fine; for a family bathroom, thermostatic is the safer pick.
Concealed vs exposed
Exposed valves mount on the surface of the wall with the pipework visible or fed from behind. They are quicker to fit and easier to retrofit or service, which suits refurbishments. Concealed valves are built into the wall so only the control plate shows, giving a clean, minimal look, but they need more work to install and access. Choose exposed for simplicity and easy maintenance, concealed for a streamlined finish where the wall can be opened up.
Valve, mixer or full shower system?
| Type | What you get | Best for |
|---|---|---|
| Shower valve / mixer | Just the valve | Pairing with an existing head or rail |
| Bath shower mixer | Valve plus bath spout and handset | Over-bath showers |
| Shower system | Valve, riser rail and head together | A complete ready-to-fit shower |
Other things to check
Confirm your water system and pressure, as some valves need a minimum pressure to perform well. Look for safety touches such as a cool-touch body that stays cool to the touch during use. Match the finish to your other bathroom fittings, and check whether the valve controls one outlet or can divert between a fixed head and a handset.
Frequently asked questions
Should I choose a thermostatic or manual shower valve?
Thermostatic is recommended for most bathrooms. It holds a set temperature and shuts off if the cold supply fails, protecting against scalding. Manual valves are cheaper but offer no scald protection and can fluctuate in temperature.
What is the difference between concealed and exposed shower valves?
Exposed valves sit on the wall surface and are easier to fit and service. Concealed valves are built into the wall for a neater look but need more installation work.
What is a shower system?
A complete set with the thermostatic valve, riser rail and shower head supplied together, ready to install.
Are thermostatic showers safer?
Yes. They limit the maximum temperature and cut the flow if the cold supply drops, which greatly reduces the risk of scalding.
Do thermostatic showers need a minimum water pressure?
Many do. Check the product specification against your water system and pressure before buying, especially on gravity-fed systems.
Shop showers
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- UK bathroom refurb supplier guide