We currently live in a 120 year old house in St.Louis. We are experiencing water damage on our interior plaster on the West wall. The top half of this wall, where most of the damage is, was tuckpointed two years ago. In addition, we had our roof (only 2 1/2 years old) re-sealed and had our parapet and coping tiles re-tucked. We thought our problem was fixed, so we replastered and then a big rain storm came a week later and stained all the new plaster in the same spots. I'm sure it will be bubbling up with the efflovesence soon and the plaster patchwork will be ruined again. I'm believing we have an old brick problem, not a tuck pointing problem. The only thing I can't seem to figure out is that this house is three layers of brick thick along with a skimcoating underneath the plaster. How am I experiencing all this damage from water just contacting with the exterior brick? Is this a situation where I should seal or is it time to rebuild the entire wall? Is it ever beneficial to stucko over all the brick on one side of the wall to eliminate this problem?