Why do some insulated tiles show up as ice-cold, and others very warm?

[Frustrated]

[asurendra]

Tiles keep temperature of material they built from. With some limitations, but generally this is true. So this exact tile was build from really cold rock

[Frustrated]

They were all built out of the same type of rock, though.  That's what the non-standard look is for.

[Red Shark]

If you harvest 400kg granite from a frozen biome, and 400kg granite from the starting ring -- they'll both be used for your insulated tiles -- but one will be -30c, and the other will be 25c.

It's the temperature of the debris that matter, not the type of debris!

[Frustrated]

Ohh, that's fascinating.  Is there any difference in their ability to diffuse heat?

[Fleetfeet]

Insulated tiles will still exchange heat with their surroundings* but, by design, will do so extremely slowly. You'd have to get math-heads to give you specific details, but over time all the tiles will equalize in temperature... just in the case of insulated tiles it'd take hundreds of cycles.

*intuitively you'd expect everything to settle at the same approximate temperature in a neutral environment and given enough time, but iirc oni's thermal calculations are wonky so that might not actually happen. In either case if you're hoping they'll normalize in temperature in 30 cycles, I'm very confident that won't happen. They'll all insulate just fine though, as evidenced by their resistance to temperature change.

[KittenIsAGeek]

On 2/16/2026 at 10:23 AM, Frustrated said:

Ohh, that's fascinating.  Is there any difference in their ability to diffuse heat?

Heat transfer in ONI isn't exactly like real world physics.  It uses similar math, but there's some rounding that happens and some not-obvious mechanics.  For example, if you have debris sitting on a tile in a vacuum, those debris will never pass their heat to the tile.  This requires things like conduction panels, or drywall (to keep liquid from vanishing) once you start working on the surface to manage heat.  

Those same debris will transfer heat to the tile they're sitting on if they are in an atmosphere or covered by a liquid.  However, the amount of heat that gets transferred will be based on the available medium -- which can be weird.  For example, lets say you have some really hot debris on the ground in a mixed low oxygen, low CO2 environment.  The debris heats up, say, oxygen at that tile on one tick. The next tick, that "packet" of oxygen moves.  Then it transfers some of its heat to the neighboring gas cells and the floor beneath it, but since it is no longer where the debris were, none of the heat from the debris gets transferred into the tile beneath it.

Or maybe the debris heats up a packet of CO2 exhaled by a dupe.  That pcaket has low mass, so it heats up a LOT more than it should.  It also has low thermal conductivity, so it stays hot for a while.. and a dupe running by gets an alert for being in a hot environment, even though all the air around that one 20g packet of CO2 is a reasonable temperature.  

Though, to be fair, heat transfer is a lot more reasonable now than it was a year or two back.  Haven't run into the 'strangely hot CO2' problem in a while.

BUT, to answer your question: No, the temperature of a material used to create an insulated tile does not affect their ability to insulate.  There will still be thermal transfer to/from the insulated materials (with exceptions), but it won't be enough to cause problems unless you're working with:

• Really really hot materials.
• Really really cold materials.
• Materials that are extremely finicky about their temperature.

An example of all three would be setting up a crude to petroleum boiler system using a volcano as your heat source.  Your efficiency of the system will improve dramatically depending on the materials (and their temperature) when you're building it.

[Alexander Block]

4 hours ago, KittenIsAGeek said:

debris will never pass their heat to the tile

This not true. Debris transfers heat, but much more slowly. The contents of containers and conveyors are also considered debris lying on the ground.

[Frustrated]

Hmm...so, should I build a bunch of storage bins in a nearby snow biome and have building materials transferred there?

[KittenIsAGeek]

4 hours ago, Alexander Block said:

This not true. Debris transfers heat, but much more slowly. The contents of containers and conveyors are also considered debris lying on the ground.

You're right.  I should have been more clear.  There's a temperature delta threshold that needs to be met for the transfer to happen, and an insulated tile will mean you need something like almost molten rock to transfer the heat.

Spoiler

This rock has been here for 100 cycles and even with the steam below it, the insulated tile hasn't changed temperature any more than others that are also touching the steam. Other buildings in the same chamber, such as a liquid reservoir and liquid valve, are also 110F from before it was taken to vacuum.

 

4 hours ago, Frustrated said:

Hmm...so, should I build a bunch of storage bins in a nearby snow biome and have building materials transferred there?

Depends on what you're trying to accomplish.  Generally I don't worry much about material temperatures unless I'm working in conflicting areas.  For example material taken from the oil biome will melt a cold biome, so if I'm building a sleet wheat farm, I do not want any hot material going there.  Also, if your intent is to cool raw materials, I highly suggest running them on rails through a liquid or high pressure hydrogen.  Steam works too, if you're wanting to take almost molten metal down to turbine operation temps.

 

Actually, it looks like there was a change in how materials transfer heat when in debris form since the last time I played.  Abyssalite and Plastic are both insulators, so their temps aren't normalizing with the rest, but I'm also used to seeing much more temperature variation.   Of course, this is in an oxygen atmosphere at 83 degrees F, so I'll have to experiment with bins in vacuum now.

Spoiler