Two weeks. I was housesitting for a friend. Very private with a pool and hot tub in the backyard and a jacuzzi in the house. I stocked up on groceries.
Last winter my wife and I rented a secluded beach house with a pool on St.Croix for 8 weeks. Were naked always except for trips to and from the airport to pick up friends and one grocery pick up when we first got there. Otherwise, we had things delivered.
Idiomatically speaking, two days. It wasn't a full 48 hours. But definitely slept nude. Stayed nude the whole day and night. Slept nude again, then didn't get dressed until a little past noon.