So I’ve got a patch of mold. I actually fixed it 2 years ago (it’s a rental) by scraping the plaster off (it’s a concrete wall) and replastering and painting.
2 years later, and it’s back. Now, there’s an internal pipe about 1 foot to the left of this patch (beyond the perpendicular wall) that had a hole in it about 10 years ago, but it was fixed and didn’t seem to have any problems for at least 5 years before this mold thing started.
Anyone have any experience with issues like this?
Odd. It’s a concrete wall? Concrete block or actually poured concrete? The pipe that was fixed, was it a supply line or drain line? I assume the pipe that was fixed is in a standard wood framed wall?
I’m also a bit curious about the exterior in this situation. Could water be coming in from outside?
Is that a water stain or just where you replastered?
i don’t have experience with concrete walls. But I do have experience with water. Water can come from VERY unexpected places. While the water line is a prime suspect, it isn’t the only possibility. Is this spot on the first floor on a slab? Could be a crack in the slab and water wicking up. Is it in a basement? Water through a crack in the outer foundation again. I had a case in my house where water condensed on the outside of a bathroom vent, ran down the outside of a couple of pipes, and soaked a carpet on the opposite side of a bathroom wall. At first glance the problem was obviously the bathroom pipes. It took a while to realize that the water problem started in the attic but not the roof. Frankly, there are two possible solutions-open up the wall and see what is going on, obviously difficult given the material, or recovering the entire area with waterproofing material, replastering, and repainting. Given the work involved with either, I personally would opt for the former. You are going to have to repaint the wall either way and knowing what the real cause is will result in a better outcome.
