Find Your Flow: Choosing a Shower Valve

You know in old movies when the toilet flushes and the person in the shower yells because the water temperate changes? The culprit is a manual shower valve. While the benefits of manual shower valves are that they’re inexpensive and simply designed, the water temperature and pressure can fluctuate while you’re using it. Since it has only one handle that turns on and off, it controls both the water pressure and temperature.

This type of shower valve is known by a few different names like anti-scald valves and mechanical valves. The beauty of the pressure balancing valve is that it balances the water pressure between the hot and cold shower valves, bringing it within a few degrees of your desired temperature. Like a manual valve, it’s not too complicated, a pressure balancing valve uses a single control and handle.

A thermostatic shower valve works to keep water pressure and water temperature consistent throughout your shower by adjusting the flow of hot and cold water. It allows you to preset the temperature via a dial and that guides the adjustments the thermostatic valve makes. There are four types of thermostatic valves: a twin thermostatic valve, a twin thermostatic valve with a diverter, a triple thermostatic valve and a triple thermostatic valve with a diverter. Thermostatic mixing valves are more complex, which makes them more expensive, but they offer a myriad of design options for luxury-style shower setups.

A mixing valve is very similar to a manual shower valve, but it’s even simpler in its capabilities. A shower mixing valve pulls water to your showerhead from both the hot and cold-water lines. Like a manual shower valve, it doesn’t regulate water pressure so sudden temperature fluctuations are possible if another sink or toilet is used. If you’re concerned about burns from sudden hot temps, lower the temperature on your water heater to below 120 degrees Fahrenheit as a preventative measure. 

In bathrooms with a shower and tub combo, a diverter valve sends water from the tub to the showerhead. There are three different types of shower diverter valves: a tee valve, a two-valve diverter and a three-valve diverter. The differences between the shower valve diverter types? Mainly how they switch water from tub to shower and how they regulate hot and color temperature controls.

A shower transfer valve brings water to several different exit points, helping you use multiple shower and bath features at once in some cases. The 2.0 version of these shower transfer valves eliminates the use of knobs in favor of digital controls.

Most shower valves feature three or four valve ports that serve specific functions. Typically, there’s a valve port for cold water, one for hot water, a valve port that sends water to the showerhead and one that sends water to the tub spout.

When installing shower valves, it’s important to plan for the future — it’s better to have an extra valve port that isn’t in use (capped) than do a bathroom remodel and find out you need an extra valve port.

A service stop is a shower valve feature that lets you shut off water to the shower valve without shutting off the water to your whole home. It makes repairs easier, especially if it’s something that might take time to fix.

If you have existing copper pipes in your bathroom, it’s standard to use a copper connection to connect shower valves. The most common method to attach is soldering, which is best done by an expert unless you have experience.

Iron Pipe Straight is a threaded shower valve connection that helps join a port to another pipe. If the pipe is copper, the IPS requires an adapter and then the pipe is soldered. You can also use IPS to join PEX plumbing.

PEX is flexible plastic tubing that’s become mainstream in new construction. Not only is it easier to install, since it doesn’t need to be soldered, but it’s also scale and corrosion resistant. In shower connections, PEX connects via a fitting that is finished by attaching a clamp.