I was just curious to see if a building made entirely out of doors could still function: , , , , Turns out, it's perfectly fine. Given that: a) Colonists can pass through doors freely, and monsters cannot, b) walls are permeable for line-of-sight and firearms considerations, there is little disincentive to simply make all your walls out of doors, aside from c) a little extra time during construction, and d) aesthetic considerations. Maybe a balance consideration, for later?
Making doors cost a plank to build should fix the problem. Makes more demand for planks too, which is good.
I like that but having a workshop that resembles a public convenience won't be everyones cup of Earl Grey Will doors work between adjoining buildings not tried it yet??
Another way of balancing it - monsters could break through doors and possibly windows faster than through walls. (When they finally discover how)