re: Patio concrete sweating

Alx, one of the biggest parts of my occupation is combatting and controlling moisture in concrete. I haven’t read anything you’ve googled. But if what it says is that moisture does not or can not come from underneath a concrete slab I can tell you that it is flat out wrong. And I can take you to places and show you. And buy you a beer in the process. shite condensates and sweats this time of year and nothing a vapor barrier can do will stop it. But saying vapor barriers don’t work is delusional. There is a reason why they are put down every day. I still don’t know what point your trying to make. I’ll again back out of the thread.