Masonry heaters: the problem with undersizing one is needing to fire more often, right?

So I've been reading about masonry heaters (Russian stoves, for the sake of searchability), and I think it's a good solution to my situation.

My situation, for what it's worth, is a 940 +- sq. ft. house, cinderblock/CMU construction, concrete slab foundation, poorly insulated, iffy windows, in southern Michigan. Around 1100 degree-days per month, base 65, per month in winter.

This winter, our first winter in the house, we're using a cheap Vogelzang Boxwood stove (wood heat only, btw, no back up). I'm biting the bullet and buying firewood, then burning it in the cheapest woodstove around. I'm trying to look on the bright side by telling myself this way I've got a baseline against which to measure future improvements. Next summer, I'll put on a couple of solar hot-air panels, and I hope I'll be able to get a masonry stove built. That should add up to a pretty remarkable improvement, if all the hype around each of those deices has any basis in reality.


Now, questions:
1. I like the look and feel of the Cabin Stove at Aprovecho: http://www.firespeaking.com/portfolio/the-cabin-stove/. Straightforward enough for a rookie to build, won't take up my entire modest living room, and affordable. But it's small. They've got it in a 200 sq. ft. space, if I'm reading right. So if I built it exactly as they did, it would be undersized for my 940 SF space, no? But that wouldn't necessarily mean that it would fail to keep us warm, just that I'd need to fire it more than twice per day, right?

2. Looks easy enough to just add some height to it, doesn't it? More courses of bricks means more mass, and if I add the courses at the middle, then the firebox and both flue channels (the up and the down, let's call them) will get taller all together. That's not something you could carry on ad inifinitum, but a little increase ought to work, no?

3. I've read what I could find at Donkey32, this limited amount of free information at the Masonry Heater Association's page, the info at stoves.ru, and the hearth.com forums (those guys are pretty suspicious of masonry heaters, wow). I've got two books ordered from the interlibrary loan: Masonry Heaters by Ken Matesz and The Book Of Masonry Stoves by David Lyle. What else can I read? It feels like there's a lot less information around than there should be.
Maybe if I read Russian, German, or Finnish I'd feel differently.


Thanks, all!
Mke

Mike,
I have David Lyle's book and kinda built a masonry stove on his recommendations. I say kinda because the flue is not finished through the roof so it's never been fired. I do remember that the total flue length in ratio to the firebox dimensions was an important consideration and extensions of the "up" and "down" flues may have some effect.
I also visited the link in your post and saw that the Cabin Stove was built with a single skin and a steel top. Adding an additional "skin" of veneer masonry and a masonry top would increase the dimensions but also significantly increase the thermal mass.
John

John Merrifield wrote:
I also visited the link in your post and saw that the Cabin Stove was built with a single skin and a steel top. Adding an additional "skin" of veneer masonry and a masonry top would increase the dimensions but also significantly increase the thermal mass.
John

Thanks, John! That's a good point, and my wife IS pretty insistent that the outside of any hypothetical heating appliance (haven't actually convinced her yet that it's a good idea) is to be fieldstone.
So that should go together well.

Vogelzang boxwoods are awesome and much underated stoves!

We have had 2 at either end of our finished basement for 10 yrs and they are our only heat. Nice warm floors upstairs, plenty warm. Ppl shouldn't underestimate the effectiveness of "cheap".

Hi Mike, I have a field stone bench, I was going to cob over it but it's just too purty. I am going to finish around the main guts with stone as soon as I can get some more fire clay.