Old house - foundation mortar crumbling
My son lives in a small two-bedroom one-story house (plus unfinished attic and basement) built in 1920. The foundation mortar is crumbling around the stones, and cracks are appearing in a couple of the walls on the main floor. The floor in one room started to sag, so he jacked that up as a temporary fix.
Whom should he call to find how how to fix this (he's heard of various types of fixes) -- a general contract or a basement specialist or someone else or a combination? The previous owner, our uncle, had tried to do spot fixes with a waterproofing company (there had been a hole in the foundation that gushed a river when it rained), but waterproofing is not what this foundation needs.
If you have ideas of what could be done, feel free to post that too. A neighbor had suggested an expanding mortar repair, another person said the house will have to be lifted with a crane and a new foundation poured, and someone else said the crumbling mortar has to be scraped out and replaced section by section.
Whom should he call? (not Ghostbusters... )