Re: floor sags in 175 yr old house
Also keep in mind that the sag didn't occur overnight, it took many years for the materials to deflect to their current state. Don't try to remove the entire sag in one jacking session, nor in one spot. A series of jacks along the area to be lifted OR lift slightly, support, move down and lift again, repeat until you get to the end of the sagging section. I would say that you don't want to lift more than 1/8" to 1/4" at a time, wait several days and do it again.
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!