Cant build floors

[Spectral]

hi so i made some planning thing and floors didnt get built but when i try to use flooring its just red and cant build, help?

[The Queen Salis]

did you use foundations or is it just a patch of dirt surrounded by brick wall?

[Ghost]

Your floors aren't working because of one of these reasons:

- It's not a foundation. Most floors are In-door only. Meaning they can only be placed indoors. Make sure it's actually an indoor building (a foundation) and not an outdoor area just surrounded by some walls. They will be "red" when the floor can't be placed. In which case, you can only plant Outdoor-floors.

- The type of floors you choose, are already placed. By default, when you make a foundation, it automatically places Concrete Floors.

The problem you are having is that in-door floors are only placed when you build a foundation. The planning menu does not count as actual buildings or foundations.