say more about a masonry stove please!! i don't know what that is! 💙
it's a very efficient and safe way of using wood fire to heat yr house!
❌️ a fireplace gives you direct radiant heat from the flames & embers, but all the hot air goes up & out the chimney. plus even well-seasoned wood only burns incompletely, especially once you've "banked" it (set it up to burn cooler & slower), so you end up with a sooty tarry chimney that needs to be cleaned fairly frequently.
➿️ a cast iron stove also gives direct radiant heat, and it stops the hot air in your house from going out of the chimney! this is an improvement for sure. but the hot air from the fire itself still goes out of the chimney, you still run into the banking problem, plus cast iron stoves tend to get extremely, dangerously hot to the touch & often don't show it. they need a lot of tending to ensure you're heating yr house safely and consistently and they just aren't safe if you have little kids or pets.
☑️ soapstone stoves are cast iron stoves with inset slabs of soapstone, a soft, dense type of stone. the slabs tend to absorb a lot of the most intense heat and gently radiate it out over a longer period of time. this helps with the risk of burns and also reduces the constant tending needed by a typical cast iron stove (but doesn't come close to eliminating it). these are pretty good. but the hot air from the fire itself still goes straight out the chimney, so you still end up losing a decent amount of heat that way. i've mostly seen them as like, conversation pieces or secondary sources of heat at best.
if only there were a way to keep the hot air inside until it has let off all its heat! enter the masonry stove aka tile stove/masonry heater/kachelofen/russian stove! ✅️✅️✅️
its firebox is designed to burn VERY hot, allowing for nearly complete combustion of the wood fuel - so almost no smoke & almost no tarry buildup. but unlike a cast iron stove, the whole thing is made of stone/brick/tile, so all that heat gently trickles through & there's no risk of burning yourself.
the hot exhaust (almost exclusively co2 and water vapor) goes through a long and convoluted chimney passageway, also made of stone/brick/tile, gradually releasing that heat into the thermal mass of the stove, until it is juuust hot enough to rise out of the rest of the chimney into the sky. this is a super super efficient use of wood - something like 90-95% of the potential thermal energy of the wood is kept inside.
because of how slowly the heat trickles through the thermal mass, you don't actually have to keep a fire burning the whole time - often people do a burn for an hour in the morning and an hour in the evening, which means it's generally less work. and since you don't have to worry about banking a fire, keeping embers smoldering, etc, you can use smaller sticks & branches that wouldn't be suitable for a log fire except as kindling. this is actually an ideal use for coppiced wood!
(side note - if you bundle up the sticks & branches into a big armful, the technical term is actually a "faggot" of wood, and no the slur didn't come from using those to burn gay people (something that actually didn't happen), it's from british slang for cigarettes & british boarding school slang)
the main downside is they tend to be BIG. you see smaller ones in modern scandanavian homes, but when you see them in historical contexts they're often like a quarter of the room. this means they're super expensive and really really heavy, so you often need to build a reinforced foundation pad for them! or at the least plan for them to be as heavy as a Big fireplace. on the plus side this means they often have (heated) benches built into them, and historically people would actually sleep on top!