I owned a home that was built 1912, and the foundation was deteriorating due to the age. When you would rub the walls the cement would shail off like sand. I was introduced to Seal-it compound and it was a life saver! I sprayed the compound on the walls until they could take no more, shortly after that, it was Amazing, the cement walls were Rock Hard, and solid! I even went as far as to have a structural Engineer come have a look at the foundation, and write a report. the report had stated that the foundation walls were structurally safe, and that we had taken the right steps to repair the foundation.