Ok, story time.
I'm doing an unofficial Lifestate Dynasty (it was going to be official, but then I felt bad for moving my Sim's non-heir child out with his spouse to a small house with all the kids I've made them have using encorsel... so I gave up officially to use cheats and add on to their house, this is besides the point) where I now have stuck floor tiles on the second floor of a very cramped house.
A while back in my game when my heir/spare duo were toddlers, my founder was going to read a book to her heir-son but she got stuck. I used Reset-Sim and all went on well, except that suddenly that floor space was completely unusable. I couldn't have my sims walk on it, place anything on it and it just kept saying there was an object there. I was confused but I just dealt with it. Now that my Sims have gained a really large sum of money over the years and my heir is old enough to take the reins I want to demolish the old house and start new, only those tiles are still stuck. I deleted everything in the house except for 2 3/4 tiles (one had a triangular piece missing from it) and then I went to town with every trick I know. When I gave up officially I put in my debug enabler and my two other NRaas mods (errortrap/overwatch). I've used the debug enabler to purge EVERYTHING in the maximum radius around the area. No use. I've cleared Caches. Nothing. I've checked for floortiles/lights/hidden objects. Nothing. There's just these floating tiles on the second floor. Nothing below them, no lights, nothing above them.
I did find a solution but it's not a very clean one. Someone said that if I evicted my family and bulldozed the lot and put them back down it would work, but I really don't want to lose all the progress with the wishes that I have along with all of their friends/family relationships they've built with people who weren't in the house to begin with. If that's what it comes down to I'll have to get to a decent place with my Sim's wishes before I am willing to evict/move out. I mean, even though I've made this unofficial doesn't mean that I particularly like breaking the rules that are there, I really just made it unofficial so that I could enjoy the family more but still have the challenge. Please, if anyone has any solution that doesn't require evicting I would be glad to hear it! I'm thinking of adding Master Controller (I've been familiar with it, but it caused issues in previous saves so I'm a little weary) but I'm not too fond of adding many other mods to my games, I recently purged a lot of my mods so I could start fresh and my game has run perfectly smooth since, I really hate to go back.