So I was going to replace my shower head, but it was on there pretty good and started twisting the shower arm. I twisted the shower arm back into place maybe too tight and tested the water and didn't see any leaking.

I was going to buy a new shower arm the next day and install, but I never told my wife to not use the shower so the next day while she showered it broke at the threads in the wall. She turned off the water called me, but it was to late. The downstairs ceiling already had water damage because it came down through the two water pipe holes in the wood above.

I cut out a piece of the drywall ceiling so I could make sure the leaked stopped and dry it out. Now I'm wondering if I need to replace the wall between the shower and bathtub because mildew, etc. The walls on the outside don't show signs of water damage.

Would the water that sprayed out just fall below and I shouldn't have to worry about the wall between the shower and tub? Are the walls usually something other then normal drywall on both sides? I used a fan to blow air into the shower arm hole. Does anyone know if that would be enough or I need to rip apart the wall?


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  • 1
    If I'm putting up tile in a damp area, I use cement board rather than drywall. Sep 23, 2019 at 2:36
  • @WayfaringStranger, maybe you are, but builders were always using water/mold resistant sheetrock. Depends on who did the work.
    – JPhi1618
    Sep 23, 2019 at 15:58
  • @JPhi1618 "Depends on who did the work" -Very much so. If they did a cruddy enough job, those nice tiles will start dropping as water leaches through cheap drywall. Chris might get a better idea of the situation if he looks carefully at the sides of the hole the pipe comes through. Sep 23, 2019 at 19:23
  • Thanks it sounds like I need a better look at these walls
    – Chris
    Sep 24, 2019 at 2:10

3 Answers 3


Chances are very good that the inside of the wall is just "regular sheetrock", and that will have gotten very wet. That fan setup is pretty cool and should dry it out since you were smart enough to cut a hole in the ceiling.

Mold grows in areas that get wet and take a long time to dry. If you can quickly and completely dry out a surface, it should be fine. Once it's dry you can spray a mold preventative in the cavity just to be sure.

More on the sheetrock... Builders use "green rock" (many names, but the front face is green most of the time) in wet locations. The front face is moisture and mold resistant, but the back of the drywall is plain, brown paper. Your water hit the plain paper. Many remodelers will use a cement board to replace the old drywall because it's a much better material that they can warrantee, but only a very high quality builder would use that, and chances of it happening go down with the age of the house.

  • Thanks i thought something like green or purple sheetrock suppose to be used from what I read, but the back like you said might be an issue. I'm going to keep an eye on this.
    – Chris
    Sep 24, 2019 at 2:07
  • Just doesn't make since why companies don't make the green rock on both sides, but I guess it comes down to money or maybe there is another purpose why the green isn't on both sides.
    – Chris
    Sep 24, 2019 at 2:31

The fact that the water drained out is good news. This means there isn't a large volume trapped in a stud bay.

I would dump some silica beads in there to absorb moisture and keep the fan running. If you get it dried out fairly soon you won't have mold (or much mold), and there won't be a need to demolish the walls.

Leaks occur in homes all the time, and unless it's an ongoing problem or isn't quickly addressed it doesn't need to be considered a catastrophe. Like others have said, you probably don't have regular drywall behind that nice tile, so it's not going to turn to mush on you.

  • Thanks for all the comments and ideas. Much appreciated like the silica beads didn't think of that.
    – Chris
    Sep 24, 2019 at 2:04

I believe a more durable, water-resistant material is used for shower/tub/bathroom walls. (See Cement board.)

You should definitely consider a replacement of the walls, and a full drying of the intra-wall space, especially depending on where you are. Using US-based locations, Florida and other humid locations may have serious potential for liquid-based hazards in confined spaces (mold etc.), while Arizona or other very dry locations may naturally dry if simply opened.

A trustworthy local contractor should be able to offer significant insight into whether or not deep intrusion was likely, and could also inspect the location. I realize this is diy se, but some things are better touched than described online. Even if significant amounts of water were not discharged, if enough water went into the wrong places in the wrong environment, the problems could become quite serious over time.

(Source: A local contractor and friend helped fix significant water damage to a house where there was minimal visible effect, and even multiple fixes had already been applied ... but the intra-wall moisture had never been dealt with.)

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