Hi Thomas,
I subscribed to permies under my old e-mail address something like 10 years (?) ago, but was just getting the newsletter and never posted or anything. Then last year, we bought this property, and I'm guessing maybe a newsletter mentioned RMHs and it caught my attention. I knew the heating system in this old farmhouse was using an old heating oil tank with ducts and vents and it didn't work, so I was looking for other solutions. I looked at RMHs, and I figure if they work for people in Montana, they'll be good here too.
In March, I went online to permies and bought the RMH movie for $15 to get a little more info on them. I finally watched the whole thing this week and bought some more of the instructions so I could get a clear idea on how it works and whether one would fit in the existing chimney/fireplace areas. That is the extent of my knowledge of RMHs. I believe I know what a J-tube is. Is a batch box just one with a bigger box so you can load more wood at a time? I'm not really clear on what would fit here.
I've uploaded a few more pictures - hopefully they help to clarify our layout. The house is a little longer N/S than it is E/W. There are two separate chimneys. What I'm referring to as "Chimney 2" in my pictures is in the middle of the north half of the house that comes down in the wall dividing a bedroom and an office, with fireplaces facing into each room, sharing that chimney. I have not actually tried to use those fireplaces yet. (The picture I took of the fireplace facing into the office in my previous post has a lot of old insulation and construction trash in it at the moment.) The other chimney, "Chimney 1" comes down in the midst of the southern half of the house in the wall between the kitchen and the living room. We did use the old wood stove a couple times during the winter and there were no immediate problems, though I agree that an inspection would probably be good before using any of the fireplaces or wood stove regularly.
For floor support, yes, I think we'll need to add more support. When we were redoing the foundation a couple months ago, we could see that the chimney foundations were about 5 1/2' x 6', but for RMH we probably need a little more. I wish I had known more about RMHs before we did the foundation, since we could have built in the extra support at the time. But we can adjust.
I hadn't been planning to put in anything upstairs, though I figured we could maybe run something up to help with heating the bedrooms on the upper floor. I was mostly hoping that since heat rises, if we heated downstairs, the upstairs would benefit enough from it through circulation. On the second floor, the north chimney (#2) is completely inside a wall. The south chimney (#1) coming up from the kitchen/LR is exposed in a bedroom which has access to the attic.
Building an RMH seems not too difficult, but really what concerns me most is the structure, making sure there is enough support underneath. I'm also not sure how to convert an existing chimney - I'd probably cause it to tumble down while I'm trying to rearrange the bricks. [facepalm]
