well, i should have taken pix, but a description should give a general idea. i am burning a vermont vigilant 2 with nut/pea mix and am running hot. just finished adding an inside coal bin, so life is easy.
i have an older farmhouse that is half log cabin structure, and half balloon frame. the footprint of the two combined is about 24X24 and 20X30, so about 1200 SF on each floor. the cabin has a walkout basement, and the frame has an earth basement. the 3rd floor is a half story with about 600 SF that i don't normally use, and have several doors isolating. the house has original windows with storms, but modern doors, and is about half insulated in the balloon section with celulose. the 2nd floor ceilings likewise.
my stove is in the walk-out basement, and the coal bin is in the back basement about 40 feet away. the walk-out basement is my hobby room, and the stove is slate hearthed and stone wall backed. the rest of the room is finished, but the floor is india slate on concrete, so a bit of a heat sink. i have 2 sizeable squirrel cage blowers bracketing the stove and drawing heat off into ducting to 12X12 grates in the floor above. i also have a cold air return to the furnace in the same room, so can run "fan only" to the entire house with the propane hot air furnace. i have added a floor fan to increase the circulation in the room so that the 16X24 return draws 85* air. the cold air return draws so much air that i have a significant negative pressure in the stairwell.
the stove was run last year with pea and rarely got over 550*. it kept the house in the 60's reliably, without the cold air return and fan only system that i added this year. i am having trouble keeping it under 750 now with a range mix of half nut half pea, and actually demagnetized a stove thermometer last week. the biggest problem i have is in getting the heat out of the stove room effectively. i would add a floor grate into the living room, but want to keep the rooms effectively isolated with regard to sound transmission. because of this i am running the fans.
the really cool part, and relevance to this thread, is the coal bin i added last month. last year i had a wooden coal bin outside, and let me tell you, that business is for the birds. walking out into the middle of the night to dig the bin out of a foot of snow to get a 5 gallon bucket of coal was not fun at all. walking into the back basement to get the same is much nicer.
the bin is in the back corner of the earth basement, about 6'X6' with a 36" door set at 45* angle on the corner, and framed with 4X4 and 2X4. it is built with end nailed wall frames that are lag bolted to corner studs with 1/8" steel clips and 1/2" lag bolts. it is floor to ceiling, and attached to joists above. i didn't have a hammer drill to secure the treated lumber plates to the concrete floor, so there are steel braces lag screwed to keep the exposed walls that are not against the foundation corner from kicking out, and depending on the loading against the foundation walls.
the wall surfaces are 14 gauge galvainsed steel sheeting i had picked up years ago for a song, hung on the interior of the framing. after framing the walls and door opening i used a 40 tooth carbide blade on a 7 1/2" circular saw to cut the steel sheeting to size (wear safety glasses and don't try this on over 14 gauge), overlapping corner studs where i could, and nailed the steel to the studs with #12 nails and a framing nail gun (needs max air pressure and dead square alignment or you get fish hooks flying back at you). the door is framed with 2X2X3/16 angle steel, steel sheeted, hinged on both sides with pipe sections, 1/2" round rod pull pins, and eye bolts into the corner 4X4 studs. it has a gravity feed chute just an inch over bucket height, and there is a window in the top of the door i can stick a rake into to pull the coal forward, so i am hoping to get 70% gravity feed.
the bin is fed via a feed chute i made up out of 14 gauge galvanised. the chute is about 4 feet long and sits at about 40* angle. it is 14" wide and 10" high on the outside wall, about 2 feet above grade, with a cap. passing thru the outside wall and over the foundation thru an old kitchen under cabinet it narrows to 10X10" before turning plumb to fall into the back corner of the bin. i cut the parts and flux core welded to make the chute, and had just enuf room to jog it in as one peice thru a hole in the cabinet floor. cutting the opening was a royal pain in the tush, but after painting the exposed areas with aluminum paint, then sealing and framing it to match the windows, it looks rather nice.
the best part was the day the coal truck showed up to deliver. the driver laid down his 10' conveyor and began to roll the nuggets and i went down to see how things were going on the receiving end. the chute fed perfectly and 3 ton ran right to the bottom of chute, up to the top of the bin in the back corner. the coal going into the chute made the sweetest sound as i weighed the effort of building the bin against the effort of running the pickup truck up to the coal yard last year and shoveling coal into the wooden bin. never again, my friends. never again.
i would have made the bin bigger, but space in the back basement was limited by plumbing and shelving and such, so i settled on a calculated 3 ton capacity. i think i could get 3 1/2 ton in, but didn't want to push it on the first fill. the coal was blascheck from Hoke Mills in York Pennsylvania, at $220/ton plus $60 delivery for 15 miles. hopefully it lasts 90 days or more. on basis of what i have seen in the last week, i believe it will.
this bin should last forever, treated lumber footed and steel lined. i am sure it will be here long after i am gone. gravity feed is a simple pleasure well earned. walking out into the dead of night in the snow and cold is a thing of the past.