What kind of paint is that? Is there any ventilation in the bathroom? If you are trapping all of that steam in the shower, then yes, I think it could definitely cause what you are seeing. That moisture needs a way to escape. That said, your neighbor upstairs might not know if her shower is leaking. People with upstairs showers may not realize they have a leak until it starts coming down below.

It could be either but on this we can all agree,bathrooms are supposed to include fans.
If the kid can use another shower without his old man hollering at him,see if the ceiling stays dry eventhough the upstairs is used. If ceiling stays dry,see if the neighbor will run cold water in her shower for a couple of hours. If no water shows after 1 hour,punch a hole in each bubble.

I manage rentals. I would clean that off with bleach and when dry press the wall. If it soft she probably has a leak. Water will travel to a low point and then drip. I would be surprised if it was your sons showering that caused the bubble. You may have to open up the ceiling to really find out and have her run the shower. But to be cheap i would suggest that if she is using a shower organizer that is hanging off the shower head she should take it down and see if that solves the issue

I just helped a neighbor who had a leak in the ceiling of the laundry room beneath a bathroom, The only leak was when someone took a shower, not a bath. In addition, the tile and caulking in the bathroom looked just fine, However, we finally noticed that some water from the shower head was getting splashed onto the tile wall and running down to the tub spout. I unscrewed the spout and saw that the plumbing came through a hole in the wall that was not caulked and the water coming down the wall would get behind the base of the spout, wick through the penetration, and find its way down to the ceiling below and travel sideways about 4 feet over to the lowest point of the ceiling beneath. Once this hole was siliconed, the problem went away. In doing some research on this issue on the Internet, I found that this is the number one issue responsible for leaks below a shower.

We've closed down that bathroom--I think actually it hasn't been used since the 16th, when I took those pics.

I'm going to pressure DH to go ask the upstairs neighbor to run her shower for a while (I want to mark the edges of some of the bubbles, so we can compare).

A few points people raised--
⢠shower organizer hanging off the shower head--Our showerhead is on the opposite (non-bubbling) wall.

⢠tub spout--no tub. These are both stall showers.
But to speak to the similar issue of moisture going through a uncaulked hole for a pipe--all the pipes are in the opposite wall, I'm certain.

⢠fan / ventilation: there isn't one; there's a window, which usually isn't opened during a shower. We can change that. (It's just that we've run showers in there for this long before, often, and this is a pretty sudden arrival. And he doesn't shower daily--more like weekly. (I know, I know.) )

â¢I really don't want to change the shower curtain to allow steam to escape around the edges--that's what's keeping The Kid from flooding out the guy downstairs w/ water that gets outside the shower enclosure.

⢠kind of paint: It's a latex made for bathrooms.

Another question: What would you do in terms of prepping that wall for repainting?

DH said, "I'll get up there right away and scrape it."

I kind of don't want to mess with it at all until we've ruled out a leak from above--I don't want to do things twice.

But I also thought that scraping is going to leave us with an uneven mess.

Would it be a bad idea (waste of energy, ineffective, etc.) to get a heat gun and remove the whole wall's worth of paint?

Of course, with either manual scraping of heat removal, we'd need to figure out where to stop; I don't think we want to strip the paint off the whole bathroom, even if it is a small room with paint only above 5 feet on the wall.

Hi, It looks like the mildew is from your shower. Lots of condensation on the ceilings and walls will cause the
mildew and paint problem. Spray the mildew with bleech and water about 50/50 scrape off the loose paint, wash with TSP, prime and paint. Use bathroom paint check to find out if the paint has a mildewicide in it.
Open the window and if possible the door when the shower is used. When showering is done leave the window and door open until the room is dry.

Woodbutcher

just read your other post about cleaning off the wall/ceiling.

did you get the upstairs neighbor to run her shower?
showers have pans, and pan leaks would also
cause this type of damage.

I'd find the cause of the moisture, from your son's
showers, or any leaks from above. fix the leaks
& then see about extent of damage.

if wall is soft behind the 'bubbles' then the
sheetrock will need to be replaced. probably
part of the ceiling & part of the walls.
once that is finished, repaint.

best of luck

Her shower probably needs new caulking. I noticed some water on my basement floor some time back (below my tub) and re-caulked everything and no more water drips.

My DH claims she doesn't have any caulking problem. But he also admitted to me that he didn't see it.

We had caulking problems and were creating damage for the guy downstairs. So, bcs some of that was happening outside the shower (16yo was letting a ton of water get outside the enclosure), we added wrap-around hooks for the shower curtain--which really eliminates the likelihood of water getting outside.
It also funnels all the steam straight up that wall.

We haven't gotten the upstairs neighbor to run her shower--maybe I'll try that this week. DH was supposed to, but he's kind of blowing it off.

Well, DH says he got her to run her shower yesterday, and there was no water intrusion. So this is all The Son.

We'll have to get him to work on taking shorter, not-quite-so-hot showers, and then also figure out better ventilation.

We've had periods where that shower was used for two showers a day, and we never had the slightest mildew or steam problem.

It's heated by a standpipe from the steam-heat system, and that's a very dry heat, which is probably why. And right now, it's cool enough for condensation on the walls to be high, and the heat's not on.

I can't really install a fan anyway, other than setting one on the windowsill and plugging it in.