I have an older house with a brick foundation. Sometime it was reinforced by sistering some concrete to it, which I guess is pretty standard. It seems to be holding up pretty well. The problem, relatively minor I think at least, is a problem above the sistered reinforcement where there is still just the brick above ground.
Last year I used an auto sprinkler which sprayed on this particular part of the foundation. I believe that to be the reason that for the first time I have ever seen, some blistering in this wall. It seems for aesthetics, the interior brick was covered with plaster, and then painted. It seems like it is this plaster that is blistering out in parts, which I have since removed the problematic areas. The rest seems fine.
Can I/should I just smear some plaster on the areas where there was the problem and paint over it? Since I have stopped using the auto sprinker, I noticed the problem seemed to have stopped getting worse, so I am thinking that stopped, I won't have the problem in the future.