I've got another structure you should make.
Charcoal Bloomeries.
Traditionally such things are outside the walls, mud and clay pressed over the structure of wood that is sealed up so that the fire burns slowly, and badly, producing charcoal over a few days. Like the grain structure this might start out as a hill where you dig out a block or two to reach the furnace that's only there to make charcoal, by the stack, and eventually will be chests and hoppers and the like to automate charcoal production.
Charcoal Bloomeries.
Traditionally such things are outside the walls, mud and clay pressed over the structure of wood that is sealed up so that the fire burns slowly, and badly, producing charcoal over a few days. Like the grain structure this might start out as a hill where you dig out a block or two to reach the furnace that's only there to make charcoal, by the stack, and eventually will be chests and hoppers and the like to automate charcoal production.