19
PSA: The old lime putty we found under a floor in Savannah is still soft after 80 years
We were doing a demo job and pulled up some rotted boards. Underneath was this gray, putty-like mortar that was still pliable with a trowel. It made me look up old mix ratios, and it turns out they used a crazy high lime-to-sand proportion back then. Anyone else run into mortar that just refuses to fully set?
4 comments
Log in to join the discussion
Log In4 Comments
drew7062mo ago
My buddy had a similar thing happen in an old Baltimore row house. He was fixing a brick foundation and found mortar he could scrape out with his fingernail. The contractor told him it was because they used pure oyster shell lime back in the day, with almost no sand. It never really gets hard like portland cement. Makes you wonder how many walls are just held together by habit.
3
margaretc422mo ago
Actually that soft mortar is a feature, not a bug. It lets old brickwork flex without cracking.
7
kevinw9415d ago
Wait, so they just straight up used lime with barely any sand? That's wild. @nancyramirez you said you found the same stuff in Philly - was it in a row house too, or something else? Feels like half the old brick in these mid-Atlantic cities is held together by luck and oyster shells.
2