We stripped the paint off our 100 year old house and repointed. However, once the paint was removed, we discovered what looks like concrete smeared all over the bricks. Our masons used muric acid and a brush, and tried to power wash the concrete off using a little bit of pressure, but they claim they can’t get the concrete off further. They say that power washing with more pressure will damage the bricks, and sanding the bricks or chiseling the bricks will break them.
Has anyone encountered this problem before? Has anyone ever minimized these type of stains by staining or painting them? We don’t want to paint the whole house again. One other thing- the concrete isn’t everywhere. Huge swaths of the house (semi attached) don’t have any stains at all. Otherwise I would just regretfully repaint.
Thanks so much!”