Pneumatic Door

Pneumatic Door is a basic building used to control access between rooms without requiring research. It costs the same amount of materials as an Airflow Tile or Mesh Tile, so replacing two tiles with a single door is often cheaper. Unlike those tiles, however, it does not provide structural support for most buildings.

A Pneumatic Door can be left open at all times, which removes waiting time for Duplicants moving through it. Even when open, Duplicants still obey access restrictions, so a door can be used to control where they are allowed to travel without physically blocking the route. Critters do not treat an open door as a barrier, which makes it possible to use open doors to keep parts of a base accessible to animals for decor or ranching purposes. This also means that a Critter left in an open door still suffers the Confined -10 Happiness penalty, and moving Critters out of a Stable can trigger room reassignment behavior that may create an endless wrangling loop.

Pneumatic Doors also interact with several other systems in useful ways. They do not block the effects of the Loud Sleeper trait, so a sleeping Duplicant with that trait will still disturb others nearby. Duplicants can stand on top of a door and climb to adjacent tiles from there, making the door a slower and less convenient alternative to a Ladder in some layouts. They can also reach through a Pneumatic Door to pick up items behind it, and fallen debris can pass through a horizontal door.

The building has a base overheat temperature of 75 °C. In hotter environments, material choice matters: Gold Amalgam raises the overheat temperature to 125 °C, which is useful in the Oil Biome, while Steel is needed if temperatures may exceed that threshold.

• Pneumatic Doors are a common low-tech way to separate rooms while keeping movement flexible.
• They can be opened permanently to reduce pathing delays.
• They preserve access control even when open.
• They do not support most buildings, so they should not be used where roof support is needed.
• They do not stop Auto-Sweepers, which can be used to isolate industrial machinery behind doors while keeping item transfer available.

There is also a known movement issue in some versions: Pneumatic Doors may fail to properly block critters and items, allowing objects to fall through them and some creatures or Duplicants to pass through in situations where the door should have stopped them.