That's still a double door by technicality, not a single door. There's a difference.
Thank you, Gage. Heavenly words.
Good thinking. Armored walls are truly useless, I've never seen the point of them.
TL;DR AT BOTTOM!!!! In the past, before the second coming of Blueprints, I would always focus on the immediate acquisition of an Armored Door. I absolutely loathe being forced to make multiple air-locks of Sheet metal doors, because it both limits space in the base (Which is ...