Sterile tiles with special cleanliness-enhancing properties. Extra-clean rooms improve outcomes in hospitals and research labs. This tile is very slow to build, but quick to clean.
- 1 × 1
- Cleaning Time Multiplier
- Filth Multiplier
- Move Speed Factor
Sterile tile has the highest cleanliness stat of all floors of 0.6.
Sterile tiles can be constructed once the Sterile materials research project has been completed. Each tile requires 3 Steel, 12 Silvers, 1,600 ticks (26.67 secs) of work, and a Construction skill of 6.
This tile is relatively slow to construct, taking almost 19x longer than a standard wood floor.
Sterile tiles boost cleanliness by +0.6, meaning an entire room of sterile tiles will have 0.6 Cleanliness. In addition, they only take 60% of the time to clean, but have −1 beauty per tile. Sterile tiles are non-flammable and do not penalize walk speed.
Cleanliness is important for a few different types of rooms and buildings. Having a high base cleanliness from sterile tiles means a greater margin before filth accumulation matters and, in some cases, provides additional bonuses. The following are affected:
- Hospitals: In a full room of sterile tiles, surgery success is increased by roughly ×1.02 from 0 cleanliness, while tend quality also increases. Infection chance per wound is also multiplied by x30%, compared to x50% at 0 cleanliness.
- While the maximum surgery success chance (98%) is possible without sterile tile, the extra cleanliness provides a buffer when patients start bleeding all over the floor and the extra tend quality can all save a pawn's life. Sterile tiles should be installed when you can afford it.
- Laboratories: Research is accelerated in a clean room by up to +9% in a sterile room, when compared to 0 cleanliness.
- Kitchens: Cooking in a dirty room has a chance to give food poisoning. However, the cleanliness only needs to be at -2.0 or higher to avoid the higher chance. Therefore, even dirt floor is sufficiently clean so long as filth is removed.
- Straw matting is sufficient and prevents 95% of accumulated dirt and trash. For larger kitchens, this will save on cleaning time. For tiny kitchens, the cleaning time speed makes sterile tile faster.
- Biosculpter pods: Pods run up to +15% faster in a sterile room. As room space doesn't matter, you can make a 2x3 room with just the pod inside it, which is easily affordable.
While Cleanliness will also increase room impressiveness, the cost and beauty malus makes it inefficient for doing so. Sculptures, when combined with steel tiles, stone tiles, or even paved tile are more cost effective (with a competent artist). If Cleanliness is desired, then steel tiles have 0 beauty, give +0.2 cleanliness, and have the same clean time as sterile tile.
In general, sterile tiles aren't an immediate priority to research. Get power, weapons, and enough defenses first so that your colony doesn't fall apart. Then you should get sterile tiles to help save lives and speed up research. The research is also a prerequisite for hospital beds (and by extension vitals monitors), which provide a further boost to medical success.
Other clean flooring
Steel tiles only provide 0.2 cleanliness, but have the same 60% cleaning time and do not impact beauty. However, steel tiles are cheaper, costing 7 steel ($16) rather than 3 Steel, 12 Silvers ($24). In addition, steel tiles only require Smithing to be researched. If silver is low (but steel is high), or if sterile tiles have not been researched yet, then these are the best alternatives, and complete replacements for kitchen.
Concrete and paved tiles have 0 cleanliness, and take a bit longer to clean (80% clean time), but are much cheaper. They only take 1 steel and 2 steel, respectively, making them suitable before you can afford sterile tile. Concrete has -1 beauty, while paved tile has 0.
Silver tiles and gold tiles are much more beautiful, and also have 0.2 Cleanliness. However, they are much more expensive than sterile tile, giving them an entirely separate use case - increasing general mood, not hospital effectiveness.
As sterile tiles are relatively expensive, you may want to initially combine hospitals and research rooms to make the most out of the buff. Otherwise, you may want to make hospitals small, to save on resources. The smallest room size to maintain cleanliness for triage is 4x5, but a single blood spill will make it dirty every time, not to mention the small size of the room reducing patient capacity. Increasing the size of the room will proportionally reduce the cleanliness impact from each individual pile of filth. You can increase the size, which increases room Impressiveness, patient capacity, and the buffer against filth, as you can afford it.
Note that the floor under a door doesn't count for Cleanliness, so you don't need to place sterile tiles on a doorway. However, filth under a door does count, and colonists stepping from dirt or sand to flooring have a high chance to create filth, so players should still place some flooring under doors.
In combination with straw matting
Combining sterile tiles with straw matting can increase the cleanliness of a room, while decreasing the amount of filth. Put sterile tile under objects that won't be walked over, such as beds, tables, and shelves, and put straw matting elsewhere. Flower pots or sculptures will offset the beauty from both tiles. Straw matting under the door is ideal as it won't reduce the cleanliness of the room but will prevent filth on that spot that can.
Another strategy is to use short entryways (roughly 3-4 tiles long) made of straw. Separate the entryway from the main room with doors so that the cleanliness and beauty penalties of straw don't hurt the room's impressiveness (the doors between the entryway and main room don't need to remain closed, however, as their only purpose is to create a separate room).
- 0.12.906 - Added
- 1.4.3523 - Beauty decreased from 0 to -1. Cleaning time factor added. Description changed from Sterile tiles with special cleanliness-enhancing properties. Extra-clean rooms improve outcomes in hospitals and research labs. This tile is very slow to build. to Sterile tiles with special cleanliness-enhancing properties. Extra-clean rooms improve outcomes in hospitals and research labs. This tile is very slow to build, but quick to clean.