Soldritch

For sure, I could totally see it being an iron age thing! And adding in solid iron trapdoors as well

That could be cool! I'd even be fine with them going a step further, and maybe using clay + hide + solid door in the crafting grid to create a sealed door/trapdoor or something.

That's what I figured and ran into with my testing as well, it didn't turn to ash but wouldn't become charcoal either. And I agree, using and removing dirt isn't a hassle at all, I just enjoy making builds that combine form + function; so having the option to make an aesthetic charcoal pit would just be awesome. Even if they leave doors as is and add in some new pieces, like airtight doors/trapdoors. I wouldn't mind spending some extra, or even more expensive materials on them. Perhaps they could even provide bonus warmth for winter or something on regular houses. Idk

I think it would be awesome to be able to make permanent functional charcoal pit structures with the use of doors/trap doors. Essentially having a regular door to go in and clear out the charcoal and replace firewood, with the trapdoor uptop serving as the airlock above the initial fire to start the process. Does anyone have any ideas on how to achieve this, or is it just not possible with the way the doors work? I thought I saw that doors counted as solid blocks when building rooms, but I guess that doesn't transfer over to Charcoal Pits? I even tried the metal doors/coke oven door with no luck. I just feel like it would be nice to be able to upgrade our charcoal pits, as we progress, rather than having a random hole in the ground. Edit: When trying this the pit would light but never started the charcoal making process, i imagine because it isn't considered "air-tight" with the doors vs. solid blocks