Sims 3 Doors Aren T Working On Second Floor

As i can recall this have been really easy to achieve in previous versions of the sims.
Sims 3 doors aren t working on second floor. I am playing sims 3 on pc and i am working on the 2nd floor. I don t recall ever having this problem before but then again i don t build houses often. I am playing the sims 4 on a macbook air. Question for the sims 3.
If you add a set of stairs on the second floor it should automatically add. At first it started with roofs not placing right. On sims 3 it will not let me add stairs it keeps saying my ceiling is to low how do i fix this or does it just mean i cannot have an upstairs. I ve also tried it with simply adding floor tiles but my roof always gets in the way.
Whenever i clicked to place the doors though it would beep at me and display the message cannot intersect stage whilst pointing to the foundation. I cannot put doors into my walls. I ve built my first house and it has two floors. Building multi floor homes in the sims 3 is not that difficult in fact it can be really simple.
If i were to try to build one on the second floor it would place it on the first floor. How do you add doors to the 2nd floor. I had to build fences round the stairs which is really strange looking when there s nothing holding up the fence. It s such a nice room too.
In ts3 there has to be a full tile between a door and an object parallel to it. Doors with glass in them are generally meant as exterior doors sliding glass doors glass pane doors or stained glass doors not leading into another room of the house. I ve built a second floor using a platform using stairs and including walls but when i get to adding doors it won t let me because it says that it can t put the door on a platform. I tried making a bedroom upstairs but when i try to put a door it tells me can t put that on a platform.
Doors need a piece of floor on either side so a door will prevent you from removing foundation. Since i used a platform for the floor of the second floor what am i supposed to use so i can put a door up there. But now i had a really hard time removing the flooring on the second floor to get the open space i wanted. If i tried to place one.
It says that i have to have a foundation but you can t put a foundation on the 2nd floor. Windows will also prevent it as will light fittings on the ceiling. If you have a poorly placed door it might not work will look ugly or even silly.