How deep does a room need to be to cancel out daylight

[SubtleOrc]

I build a cellar underneath my kitchen and it's perfectly lined on all sides with solid granite rock. With no light source in the room it's still very very bright during the day. Looking at the unreliable wiki there is a mention of skylight? So.. How deep do I need to build my cellar, or how many layers of rock under my kitchen floor do I need to go before i don't get daylight creeping in?

 

Also, whilst we are at it.. if the ambient temperature is 5 degrees or less then whats the rate of preservation i can expect in a storage vessel in a perfect cellar. Mine seems to vary somewhere between about 0.12x and 0.2x depending on conditions

[ooof1000]

the cellar needs to be made of constructed materials like cobblestone and bricks to be counted as sealed

[Michael Gates]

When the documentation for this talks about not letting sunlight in, it's talking about direct sunlight, a straight path in where you can see the actual sun. The sort of indirect, ambient lighting you get down a corridor and around a corner isn't an issue. So, if your kitchen is an enclosed room, you've got a tunnel down to the cellar (or stairs), a solid door at the bottom, and then the cellar is behind it, that counts as "no sunlight."

Multiple layers of material don't matter. When the game is looking at "how effective is this cellar?", it looks at the insulating surfaces that directly enclose the room; anything behind those gets ignored. You can actually mess up your cellar by adding decorative wood ceiling beams, even if the structure itself is solid stone.

[Professor Dragon]

On 7/15/2025 at 12:53 PM, SubtleOrc said:

I build a cellar underneath my kitchen and it's perfectly lined on all sides with solid granite rock. With no light source in the room it's still very very bright during the day. Looking at the unreliable wiki there is a mention of skylight? So.. How deep do I need to build my cellar, or how many layers of rock under my kitchen floor do I need to go before i don't get daylight creeping in?

 

Also, whilst we are at it.. if the ambient temperature is 5 degrees or less then whats the rate of preservation i can expect in a storage vessel in a perfect cellar. Mine seems to vary somewhere between about 0.12x and 0.2x depending on conditions

Is your main concern "making a cellar" or "blocking out all light"? Because they are different.

A cellar functions just fine, even above ground in the sky, with a single solid block lining of appropriate material.

The sunlight can be blocked with a zig-zag.

Having said that, I've had some weird variations where I build the same design in my survival world, that I've just built in my test world, and get different storage rates on storage vessels. Altitude and climate both impact the storage length.

You might be interested in this Reddit discussion:

 

 

And that storage rate that you're getting is in line with my experience for a decent cellar.

Edited July 19, 2025 by Professor Dragon

[ijkdenem]

i thing it partially depends on what light source you use and how much of the light i shined in the "hole".

Edited July 25, 2025 by ijkdenem

[Dilan Rona]

On 7/18/2025 at 11:43 PM, ooof1000 said:

the cellar needs to be made of constructed materials like cobblestone and bricks to be counted as sealed

Mine is made of dirt, and packed dirt still, with a solid wood door, and I got no issue with the room. Seals just fine. Doubles as my kitchen as well, with an upstairs cellar (that is still mostly empty, been putting off moving the food storage trunks from the kitchen to the upstairs cellar). I just have a habit of forgetting to close the door behind me sometimes.

[trollocat]

On 7/14/2025 at 11:53 PM, SubtleOrc said:

I build a cellar underneath my kitchen and it's perfectly lined on all sides with solid granite rock. With no light source in the room it's still very very bright during the day. Looking at the unreliable wiki there is a mention of skylight? So.. How deep do I need to build my cellar, or how many layers of rock under my kitchen floor do I need to go before i don't get daylight creeping in?

 

Also, whilst we are at it.. if the ambient temperature is 5 degrees or less then whats the rate of preservation i can expect in a storage vessel in a perfect cellar. Mine seems to vary somewhere between about 0.12x and 0.2x depending on conditions

I know I'm late but the solution for anyone wondering is:
Go to every corner of the cellar and type '.debug relightchunk' in chat until it's completely dark, the game sometimes doesn't recognize that there is no sunlight anymore where it used to be