I'm sorry if this is wrong place to post it, I don't usually ask questions around here as I'm able to find answers when I look well enough but this time I couldn't find anything related to my issue.

Ok, so I had a house on 25x25 lot and built myself a basement. I wanted to create a huge dungeon so I decided that 25x25 lot is not big enough and relocated my house to 64x64. But the basement size is still the same - the grid size on which I can build is still 25x25. When I płace the basement on my lot underground it just looks like its off the bounds, there's no floor tiles and I can't put anything there. How can I fix this? Is it even possible?

Here you can see the actual size of the lot - it's 64x64. The foundation of my house is only big enough to fit 25x25 as that was the previous size of the lot.


Here is the basement level - as you can see, the grid is still 25x25. I wanted to extend the hallway and put another stairs there. But when I do that, the part that is off grid cannot have any flooring or items put on it.



When I go even lower the grid size is just fine.


It's the first time I've ever relocated a house to a different lot... I don't really know how to fix that.
Also, sorry for any mistakes in my English.

I'm not sure if I understand entirely but those blue squares on ground level is your current basement space so you need to take the basement tool and add to it from the ground level. Then go to basement level to build within whatever surface area you covered.

On the third picture you can see that I added more basement on top, but it shows as "off grid".

I'm a bit rusty when it comes to TS3 actually. The only idea I can come up with is to use that lot basement for something before you move the new house there. Like put down a basement on the new lot first, and then move the house over.

These bugs arn't always fixable I'm afraid.

You might try leveling the ground underneath the whole lot with CFE false(turn back to true when done). I think this is possibly a problem with different build levels. I would start at the section of your saved lot and drag leveling tool across new lot sections. Here is tutorial for this Link

If you use custom created world, I guess that issue can be caused by CAW. I'd rather relocate this 25х25 lot to another neigborhood. Try to place your 25х25 lot in world from any EP on 64x64 lot that already existed. If that won't work, attach shared package to your post and I'll try to find a solvation.
Regards. Vic ^_^