I want to drylok the basement but want to get the old paint off first? sandblasting? how do you sandblast? rental?
Just an idea, but maybe good old fashioned elbow grease such as scraping might work. Also depends on the type of paint they used before on the walls. If it was an oil based paint, then some kind of chemical stripper might be an option. Sandblasting sounds a little dramatic, but if the paint is that heavy that might be your answer. Best of luck to you middie, plumber Tom