Guest Bathroom: Water We Doing?

I almost can't believe that's the worst best pun I could come up with for this post.  But those you who know me well enough have probably heard my "deer" jokes at least twice, so maybe I should believe it.

Anyway.  The point of that terrible pun is to say that we finally figured out what was actually causing the water damage in the bathrooms.  Given all this nastiness, we thought it was a faulty ring on the guest bathroom toilet (read about that here).

But even after we'd done all sorts of work to the guest bathroom, the master bathroom was still moist.  And, reflecting back, our master bedroom had always stayed pretty damp (we had mildew that built up on the windows and in my corner of the master bedroom).  So while I was hanging wallpaper, Mr. Great Indoors started wondering what the problem might be.  He looked through the handy hole in our master bathroom wall and saw some drip marks in the space between the master shower and guest tub.  On a whim, he turned on the shower... and watched as water dripped steadily from the shower valves into the muck and mildew below.

Gross, right?  Well, it turns out that the builders of this house (thirty years ago!!) didn't properly install the shower valves.  They looked like this when Mr. GI took them out of the shower:

But they should have been wrapped with thread seal tape to make the threads seal appropriately.  Obviously, I'm no plumber, but this is what I gleaned from conversation with the mister. According to the all-knowing Wikipedia:  "The tape is wrapped around the exposed threads of a pipe before it is screwed into place. The use of PTFE tape in tapered pipe threads performs a lubricating function, which more easily allows the threads to be screwed together, to the point of deformation, which is what creates the seal."

So he pulled out both valves and got them wrapped up nicely.  He called it teflon tape, but there are a few other terms for it.

In the week and a half or so since he whipped up this fix, we've noticed considerably less moisture in the master bathroom and bedroom, and things seem to be drying up nicely.  Unfortunately, we still have this mess to contend with at some point.  Oh yeah, and finishing up the guest bathroom (some day I'll quit being a bad blogger and finally give you a few more updates).

It gives me the heeby jeebies.

We're so thankful, though, that Mr. GI solved the real problem, especially since we would have gone through all the trouble of remodeling two bathrooms and still not solved the real heart of the issue.  I think I mentioned it before, but this had been going on for THIRTY YEARS.  Goes to show that "builder grade" homes really haven't changed too much, have they?

Edited to add:  I should mention that it turns out there is a sump system in the space between the guest tub and master shower (our inspector didn't even know there was a sump system in the house).  The pump had been helping keep the water from causing too much more damage, but obviously our problem overwhelmed the system.

What interesting situations did the builders of your home leave you with?  Any other mildew fighters out there?

Follow along with the rest of our bathroom adventures: our dream, the before, mildewwww, every day we're drywalling (another a terrible pun), the our thrifted finds so far, ripping out wallpaper, making up my mind on a wall color, rehauling the vanity, an updated to-do list, a teaser of the floor, cleaning and wallpapering, painting, laying flooring, polishing up our light fixture, plus my Pinterest boards for the guest bathroom and master bathroom.