The other evening I stepped into the walk-in closet and was surprised to find water dripping from the ceiling. Based on the location of the rooms and walls, I quickly realized the bathtub/shower is located directly overhead and my teenage daughter was taking one of her long showers. I ran upstairs and asked my daughter to turn off the shower. I had the kids use another the shower in a different bathroom until I could work on the problem the following weekend.
Finding the Shower Water Leak
My suspicion is the leak was coming from either the shower water supply or drain plumbing. The problem is that I had no access to the shower plumbing as it was sealed behind the drywall – often there will be an access panel, but there was none. I would have to cut a hole in the drywall in order to examine the plumbing.
Showers and bathtubs can be creative in the way they leak. It’s a matter of remembering that water runs downhill and tracing the leak to the source.
Aside: I recently had the “pleasure” of fixing a leaking shower drain in the master bathroom
Cutting an Inspection Opening in the Wet Wall
I began by locating the center of the wet wall (i.e. wall with the plumbing). I gently probed (don’t want to puncture a water pipe!) for wall studs by driving a small finishing nail through the drywall to see if it contacted a stud, moving the nail about one inch left and right until I had cleared a 6 inch length. There shouldn’t be framing studs in the center area of the wet wall to allow room for the shower valve – and I found my assumption was correct.
Here’s a closeup of the nail and test holes.
Now that I had confirmed there are no wall studs in the center section of the wet wall, I used a Rotozip spiral saw to cut a small inspection hole in the drywall.
I cut only a small hole because:
- I would have to repair the drywall later and small holes are easier to fix than large ones.
- Wallpaper is hard to repair as seams will show.
- I needed to locate the plumbing and wall studs before going further.
The small inspection hole (above) allowed me to reach inside and locate the wall studs and plumbing; I also confirmed there was no electrical wiring in the wall. The inspection opening was enlarged to the span the width between the wall studs to dimensions of ~10.5 inches wide and ~8.5 inches tall.
Below is a closeup of the hot & cold copper water supply pipes and the PVC overflow drain for the bathtub. An immediate concern are the greenish/white streaks on the copper pipes from dripping water. The pipes were dry and at this point I wasn’t sure if this were a historical artifact or recently made.
A strip of blue masking tape was applied to the bottom edge of the opening to reduce the amount of drywall dust rubbed off on my arms.
Water stains on the drywall ceiling below the bathtub are apparent in the photo below. Click on the picture for a larger view.
Check the Bathtub Drain for Leaks
A flashlight and mirror are used to inspect the bathtub drain for leaks. The bathtub was filled with several inches of water and allowed to stand for 15 minutes. No leaks were found at the bathtub drain.
Check the Shower Plumbing for Leaks
I turned on the shower and used the mirror and flashlight to inspect the copper piping, shower valve and shower head arm. Bingo! Lot’s of dripping water coming down.
Below is a picture of the shower valve with wet streaks and water drops ready to fall. (Click on the image for a larger view.)
Uh Oh! I thought. If the shower valve is bad then I’ll have to cut another access opening in the drywall in order to replace the valve. That would be an ugly drywall repair. Notice the water stains on the drywall and chalky deposits on the copper pipes. The drywall integrity was fine – dry and solid – in spite of the water stains. I gave it a good shot of Lysol to discourage mold.
Upon careful inspection with the flashlight and mirror, I was able catch a glimpse of the water dripping from the shower arm (i.e. up high by the shower head) onto the shower valve. Good – at the least the shower valve is not leaking.
Water is dripping on the subfloor from the shower arm and elbow in the photo below. The white stuff on the 2×4 base plate is drywall dust.
Here’s a view of the shower head. The leak is coming from inside the wall at the connection between shower arm and elbow.
The shower head and wall flange were removed to get a look at the plumbing inside the wall.
This project is continued in Part 2.
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