Is it possible to change a faucet or showerhead without changing the existing valve?

Answer: Yes
Explanation: As long as it lines are long enough

Answer: Yes
Explanation: Yes if as long as they match up and will work with the valve . Shower heads can usually always be swapped out for a different one

Answer: Yes
Explanation: There are different trim kits that you/or your plumber can purchase to change the look/newness of your existing valve.

Answer: Yes
Explanation: Yes you can change a shower head without changing the valve , you can rebuild a faucet valve body or replace the faucet

Answer: Yes
Explanation: Only if has to be replace a cartridge moen or delta

Answer: In some cases
Explanation: Showerheads can be replaced without changing out the valve. However, there is limited availability of tub/shower faucet replacement parts for older valves. If the parts are not available for a repair, then a new valve will be required.

Answer: Yes
Explanation: Showergeads are cosmetic as well as the trim, the valve can remain the same insure wall.

Answer: In most cases
Explanation: Depends on the age of the valve. It if often better to change supply valves at the same time the faucet gets replaced, due to calcium build up and just over all upgrading valves and supply lines.

Answer: In most cases
Explanation: Shower heads are separate from the valve and can be changed that goes for some faucets.

Answer: Yes
Explanation: Yes, ask a plumber

Answer: Yes
Explanation: Either under the sink or in the shower if the shut off is in good condidtion there is no need to replace.

Answer: In some cases
Explanation: which valve is being referred to?

Answer: In some cases
Explanation: Each manufacturer has its own styles. Shower heads can be replaced without touching the valve. Faucets however typically need to replace the entire assembly.

Answer: Yes
Explanation: You can change the shower head tub spout and trim kit without changing the valve