Leak from Shower

[Bob Simon]

For the past several months I've had an occasional leak from my second floor bathroom into the front hall. After completely caulking the area (thanks for all the great caulking advice on 12/29 and 12/30) the problem remains.

Last weekend I opened the ceiling over the hall and was able to actually see it happen. When my wife shut off the shower, a thin but steady stream of water came down for about two seconds. I cannot repeat the problem by opening and closing the valves or diverter, which makes it difficult to know how to proceed. My wife says she opens the diverter before shutting off the water. This is a three handle system and it's around 30 years old.

Given all this information, is there a clue that I missed as to the likely cause of the leak? Is the best course of action to remove the splash panel and replace the mixing body along with valves and diverter? I suppose it's also possible that the leak could be from the hot or cold water feeds, or the lines to the shower head or tub spout.

[Jeff Wisnia]

I'd suggest you first check the diverter valve's shaft packing gland (or perhaps it's an O-ring seal).

I had the same sort of problem on one of our showers, and after changing the diverter valve seal I made a little sheet brass chute fastened in place with silicone caulking. That chute will direct any future leaks from the same source out in front of the tiled wall, behind the single handle valve's trim plate. That plate already has a notch on its bottom to accept any leakage from the main valve shaft, whose seal's leakage point is already in front of the tiled wall.

Jeff

[Bob Simon]

Is there any way to tell if the diverter seal was the cause of the problem other than by replacing it and seeing if the leak stops?

[Malcolm Hoar]

If the leak started some time ago, you'll likely see some evidence -- limescale deposits and corrosion around that area of the valve.

It was very apparent when I had a leaking valve stem on a shower faucet last year.