Do we know how much more efficient the thermal barrier is in a room with different wall types?
Also, if a cooler is already underground, does it matter whether it is "double-walled" by rock? Does it matter whether the walls are rock or stone?
Do we know how much more efficient the thermal barrier is in a room with different wall types?
Also, if a cooler is already underground, does it matter whether it is "double-walled" by rock? Does it matter whether the walls are rock or stone?
Walls are all the same regardless of material and rock acts the same as walls. It doesn't matter if a room is surrounded by plasteel walls or wood walls or unsmoothed granite so long as theyre all the same thickness. And thickness is a binary - all 1 thick walled rooms are the same as each other, and all 2 or more thick walled rooms are the same as each other but better insulated than the 1 thick walled rooms
Obviously you so need to be able to vent the cooler heat out somehow if you're underground though