Bulkhead

[Nullpersona]

Horizontal airlock door 3x1 building with built-in central ladder section.

When closed, functions like tile, when open, functions like a ladder in between two empty spaces.

When closed, can be walked over, or used to hold materials.

When open, jumping is required to cross, but ladder section is usable.

Since ladders don't interrupt materials falling, integrating a section into the bulkhead ensures dupes can cross by jumping, creatures cannot cross, and ladders are not interrupted.

If the door animation includes an additional piece that covers the central section, this could be used with automation as lift/elevator safety, closing around the piston, without pinching, as the lift rises.

That is, if piston lifts are a consideration, otherwise a horizontal door with ladder section.