Base Building-Ceiling Issue

Below are two screens with the beginning of my base. However, am I doing this wrong? I am attempting to make a 4 square foundation into a 10 level tower,however…I am unable to place ceilings on the pillars except for the one shown already placed by the ramp.
For the life of me I cant figure out why. My placement shows red without it ever going green in hover. I have all the pillars placed and filled, I dunno.
As well, used the rust base builder and it worked to spec,so…following those specs…it “should” work

You cant place pillars in the center of a foundation like that, you have to do it after the ceiling is on.

and i may be wrong, but the ones on the center of the wall prevent ceilings too. haven’t tested that one specifically though

Thanks, I’ll have to check and see

Yeah too many pillars.

Next time look at your foundation. A ceiling is the same size as a foundation. Put a pillar on each corner of a foundation and you can place a ceiling as well… putting one in each corner followed by extras in the middle of each corner will screw the whole thing up.