Comparison guides
Thermostatic versus manual shower valves
A manual valve controls temperature by hand and can scald or run cold if someone elsewhere in the house uses water; a thermostatic valve holds a set temperature automatically. The difference matters most in households with children or older people.
Frequently asked
Are thermostatic valves compulsory?
Building regulations require scald protection in certain new or rented bathroom installations, which in practice means a thermostatic valve or mixer.
Can a manual valve be upgraded later?
Usually yes, though the pipework and wall opening for the new valve body may need reworking rather than a straight swap.
How to choose
Thermostatic valves are effectively required where young children, older or vulnerable users will shower, because they cut flow if the cold supply fails.
Manual valves are simpler and cheaper to service, and remain common in single-occupant or low-risk bathrooms.
A thermostatic valve needs a reasonably balanced supply to work well, on very unbalanced pressure it can hunt or restrict flow rather than settle.
Connected pages on this site
Not sure which option suits your property?
Most of these decisions come down to what is behind the wall and under the floor. A site visit settles it quickly.