Filth

Filth is a broad term for any of several types of tile effects, all of which possess unique in-game appearances and negative beauty and cleanliness stats. Filth is often spontaneous and unpreventable, with potentially disasterous consequences.

Many colonist tasks are directly impacted by the nearby presence of filth. The cleanliness room stat affects food poisoning, room quality, research speed, medical tend quality, and surgery success chance.

Filth is also a major factor on your colonists' mood. Pawns who have been in a filthy, ugly environment too long will gain a negative thought. Filth can quickly destroy the quality rating of an otherwise fine room, too, depriving your colonists of potential positive thoughts.

Generation

Filth is most frequently a problem on hard floors like concrete, wood floor, or rough stone. These hard floor-types accumulate dirt from pawns much faster than natural terrain, like soil or sand. Several types of filth may stack on the same tile at the same time, with cumulative beauty effects. Filth does not hinder movement, manipulation, or field of view.

Some types of filth like "foot-traffick" dirt and colonists' trash are passively emitted periodically. An animal's filth rate determines how often it spontaneously produces animal filth on hard floors. In general, large animals produce a lot of animal filth and should thus be kept off of hard floors using zones. Smaller animals like the husky or cat have filth rates equal to or lower than humans. Hay floor can be used to absorb some animal filth, but it is highly flammable.

When a pawn is moving from terrain to floors, there is a chance for a pawn to track filth along their path for some number of tiles.^{[Detail needed]}

Interactions

Filth is removed from a tile by colonists assigned to Cleaning or by rain if unroofed. Only filth in the Home area will be cleaned; tiles outside the home area will be ignored. By default, a home area is automatically designated around new player structures and zones (this setting may be toggled in the lower right corner icon bar). However, home area designation is not automatically removed from an area even if player structures are removed. Limiting the home area of your colony will substantially reduce cleaning demands on your colonists.

All colonists clean tiles at the same rate, but some types of floors, like Steel tiles and sterile tiles, are faster to clean than others. Some types of filth, like pawn trash, are faster to clean than others, like bugblood.

Natural terrain does not collect "dirt" from foot traffic, and therefore may be cleaner and more beautiful to use than constructed floor with multiple stacks of filth, especially around animals. However, soil tiles are inherently dirty, of neutral beauty, and have a walk speed penalty.

Summary Table

Certain unsightly objects, i.e. vomit, have one value when under a roof and a lower value when unroofed. This simulates the general disgust of seeing eyesores indoors versus encountering them outside. Some messes can be spread by pawns tracking through them and others can be washed away by rain.

The effect of filth on outdoors beauty is 30% of the effect indoors.

Name	Source	Beauty (indoors)	Beauty (outdoors)	Cleanliness	Trackable	Washes away	Work to clean	Days to disappear	Notes
Amniotic fluid	Fluid produced when an animal gives birth	-30	-9	-5			70	35 - 40
Ash	Produced after flammables catch fire	-20	-7	-5			70	10 - 15
Animal filth	Produced by animals when walking on constructed floors	-15	-4	-5			35	45 - 50
Blood	From a bleeding human or animal	-30	-9	-10			70	35 - 40
Bugblood	From a bleeding insectoid	-40	-12	-15			80	35 - 40
Building rubble	Debris created by collapsed structures or during mental break	-15	-4	-5			35	45 - 50
Chemfuel puddle	Flammable puddles created by incendiary weapons.	-10	-3	-15			70	35 - 40	It can be lit on fire, and despawns on its own. 150HP and 2.0 Flammability
Corpse bile	From a rotting corpse	-50	-15	-20			80	35 - 40
Dirt	Produced by humans when walking on constructed floors or rough stone after dirt	-15	-4	-5			35	45 - 50
Firefoam	Fireproof foam from a firefoam popper	-25	-8	-5			100	5 - 10	Prevents fire from igniting.
Hair	Produced by changing hair at a Styling station	-10	?	-5			35	30 - 40
Rock rubble	Debris created by digging into mineral rocks	-15	-4	-5			35	45 - 50
Sand	Produced by pawns when walking on constructed floors or rough stone after sand	-15	-4	-5			35	45 - 50
Scattered sandbags	Remnants from damaged or destroyed sandbags	-15	-4	-5			35	45 - 50
Scattered slag	Spawned by crashed ships	-15	-4	-5			35	45 - 50
Slime	Found after opening a cryptosleep casket or during infestations	-25	-8	-5			70	35 - 40
Pod slime	Produced from a completed or rejected cycle in a Biosculpter pod	-30	-9	-5			70	35 - 40
Trash	Produced by humans when walking on constructed floors	-15	-4	-5			35	45 - 50
Machine bits	Produced from completing the "Shred Mechanoid" bill	-10	?	-5			35	45 - 50
Vomit	Vomit from a human or animal	-40	-12	-15			70	35 - 40
Water puddle	Produced by Waterskip psycast	-10	-3	-5			30	0.2 - 0.4	Prevents fire from igniting.
Floor drawing	Drawn by a child colonist	0	0	0			?	?
Flammable bile	Flammable puddles created by the Fire spew ability	?	-4	?			?	?	It can be lit on fire; has properties similar to chemfuel puddles.
Spent Acid		?		?	?	?	?	?	?

Version history

• 1.1.0 - Ashes from burned plants and buildings now survive rain and disappear after 10-15 days. They’re also visually larger.
• 1.2.2753 - Dirt now washes away in rain.
• Ideology DLC Release - Added pod slime.
• 1.3.3066 - Rain washes away more filth types. Added an alert which tells the player high filth-producing animals are indoors without straw matting floor type. Indoor rooms with non-water flooring can have animal filth or trash spread on them.
• Biotech DLC Release - Added floor drawing, spent acid, and flammable bile.