Sipping Tea...

[Lapaige46]

"Essentially, I had to pretty much demolish and rebuild most of the house to add stairs to the basement."

That's not going to happen!! I worked too hard to get it just the way I want it.

I was willing to remove the stairs I have there now and use a straight up flight and put the stairs to the basement behind them where I have the office so I removed as much of that as I could without having to replace any of the structure.

There was this guy :

Okay - so here is how you do this:

Use the Basement tool in the build mode for your house to add the basement. You add this by going to the foundation level and dragging out the basement shape.

Go to the ground floor level above the basement and select the stairs you want. Do NOT delete any floor squares (the things your Sim walks on) - doing this will cause you to create a small stair case to the foundation level. You'll notice that by default stairs try to go up. Holding shift will cause them to go down - and suddenly your stairs will go though the floor squares and the foundation to the basement below. This works for spiral staircases too.

I'd like some of what he's smoking.

[MrsFlynn]

I had a feeling you might not want to rebuild the section of house. When I rebuilt-ish Claire's house I did it in stages.

I was going to offer to help, but if it's the house I'm thinking it is, I'd have to have the shell of the house without the CC windows.

There are some players who have claimed to be able to place basement stairs inside a house with foundation with a build cheat. I've never gotten that to work.

That's why I was suggesting to basically rebuild the section of house you want the stairs to be in.

[Lapaige46]

It's the new house I just posted all the pix for. The basements is an afterthought and I think that now is the time to do it because I don't have anything done upstairs yet. The best thing to do right now is to tear down the area behind the existing stairs since I put an office in there because I couldn't really see what was in that corner. I went for a walk around the building in the halls - it's a very long building' - up and down the stairs - 4 floors - and now I have a headache because I'm hungry. Time to eat.

[MrsFlynn]

That's the house that I was thinking it was.  Do you have a copy of it before you started furnishing/decorating that I could try adding a basement to?  Or are you thinking of waiting til later and giving it another try?

[Lapaige46]

Oh, I might. I have to check in my daily saves folder. I must have one where I was just starting. Good idea.

[MrsFlynn]

Hopefully you're able to find a backup copy of the house to work with.

[Lapaige46]

Hopefully you're able to find a backup copy of the house to work with.

I found an early save that had no furniture and I can make it work without destroying half the house. The only problem is, I can only extend the basement by removing all the furniture, windows and doors and that can be done one section at a time. Time consuming to be sure, but at least I figured out how to do it....I hope. 

[MrsFlynn]

Sounds like you've got a great plan!!

[Lapaige46]

I have the stairs down to the basement and I'm now deleting foundations bit by bit. I have to move everything including windows and the ceiling beams, etc. As you can see, I'm slowing removing the foundations underneath by removing everything above them. Then replacing the floor and the objects.  (Lesson learned - delete the inside foundation bits before you build on top of them).

[MrsFlynn]

I am happy to see that's working for you. When I've tried building a basement like that I end up getting a message of something like can't place stairs inside foundation, or the game just not allowing to place stairs.