Before and after RMH numbers?

Hi Everyone, long time lurker, first time poster.

I've been reading up on RMH heaters for years now, they've always fascinated me, but never had one myself.

We are set to move from our current house to our new house in mid September this year. I am throwing the idea around of installing an RMH in the new house, but haven't made up my mind.

In the current house I have a 10 year old Blaze King "King" model stove, and we do love it. The firebox is huge, and we can get super long heat times out of it. The house is 2400 square feet, in central/northern Canada. We burn roughly 6 cord/year to keep the house nice and toasty. We basically only burn Douglas fir, as it's the only decent wood we have around. No good hardwoods available unfortunately. We have a pretty long heating season here, with the middle of it seeing some extremely cold temperatures, down to minus 40F sometimes for a couple of weeks.

The new house has an older model stove, so now comes the decision if I get another blaze king, or if I install an RMH. I've never even set foot inside a house using an RMH for heat, so I have literally zero first hand experience with this.

Here is my questionnaire I guess you can call it, for people who made the switch:

-How big is your house in square feet?
-Where are you located? (approximately)
-How long is your heating season?
-How cold can it get where you are?
-How many cord do you burn now?
-How many cord did you burn before?
-What Stove did you make the switch from? Even if you don't remember the model, a rough year of vintage would help.
-How warm do you like to keep your house?

Sorry for the questions, but most of the reading I have done over the years have extremly vague details, and I need some concrete answers if I am in fact going to make the switch. The last thing I want to do is take on this big project, just to have the family freeze this winter, and possibly end up with burst pipes or something because I didn't do my due diligence. I see talk of massive wood savings, but many of these testimonies leave out some crucial details, such as what stove you made the switch from. The wood savings switching from a blaze king may look extremely different from the wood savings switching from an old fisher. Also, someone in the southern US may already use significantly less wood than we do here in northern Canada, so it's nice to know where the info is coming from.

We like to keep the house right around the 22° C mark in the winter, I think that's right around 72° F or so. Does an rmh keep the entire house at a stable temperature? Or if it's hours after the burn, do you have to get close to the mass to feel any meaningful heat?

If any owners could answer the questions posed, it would sure give me some better ammo to best make my decision, and I would be extremely appreciative.

Doug fir can burn well enough when seasoned, we used that extensively when I lived on Orcas Island WA for a year.  As you point out, it sure helps to have a good stove.  
To offer advice,  I guess folks would like to know about the new home. Is it approximately the same size, 2400 square feet?  

Congratulations on the new house, I am sure this is an exciting time for y'all

a montana winter with 0.60 cords of wood





Ernie Wisner compares a conventional wood stove to a rocket mass heater




comparing a wood stove to a rocket mass heater

Rico Loma wrote:
To offer advice,  I guess folks would like to know about the new home. Is it approximately the same size, 2400 square feet?  

Oh I'm sorry, I should have mentioned the new house is 2500 square feet, so virtually the same. The layout is a half basement, so its roughly 1600-1700 square feet upstairs, with a 800-900 square foot basement underneath the kitchen and living room. The bedrooms on the far end of the house with no basement underneath.

paul wheaton wrote:a montana winter with 0.60 cords of wood

Paul, how big is your home? Did you heat that same home with a wood stove before? If so what year was the wood stove?

Being from Canada, I can't say I know exactly what a Montana winter is like temperature wise, or how long it lasts. Around here it's not abnormal to have a small fire in the nights starting in September, and doing the same nighttime fires as late as May. From October to April it's day and night fires, with our December to February months averaging -20C all the way down to -40C sometimes for a few weeks. The colder temperatures can often roll over into the first half of March as well.

Hi Justin, here in Western Montana, we are not quite as cold as your location.
But like you, our fires start in September and easily go into May. March is fully capable of at-or-below-zero temps.
As a long-time lurker interested in RMHs, I assume you have seen my shorty core build.
Our house is small, apx 600 squ ft.  An original 96-year-old 300 squ ft log cabin with 5 additions. Long with lower doorways that make it hard for heat to travel.
For 40 years, we heated with a homemade stove, A two foot piece of 20" Alaska pipeline, 3/4" thick, with a homemade door.  I estimated we burned apx three cords a season. It was always hot in the cabin, getting colder as you headed through the kitchen addition to the bathroom and the laundry room additions.
We have an original wood cook stove in the kitchen that we used to keep that end of the house warm during extreme temps.  In later years, we installed a small, non-vented propane heater in the bathroom addition to make sure no pipes froze overnight.

Then I built Shorty. OMG, having 500 clay bricks and an insulated firebrick core in your home is mind-blowing!
When you enter our home now, as soon as you step into the kitchen, the warmth envelops you completely. As you move through the house, the temperature doesn't change; it's just as pleasant in the back bedroom as it is in the farthest addition laundry room, or three feet away from Shorty. We now have windows cracked open all winter, at times even overnight!
The only issue we have found for us is that during early shoulder season, it is almost impossible to use Shorty without overheating everyone.
Our answer is the kitchen cook stove. For chilly mornings or rainy days, a quick fire in it is perfect to take off the chill without overheating the house.
Last year, as an experiment, I separated one cord of doug fir and larch, to be used exclusively in Shorty.
We like our house warm, so by spring I had used one full cord and perhaps another 1/4 cord.
So, although the 3-cord figure is a guess, Last season I only used 1.25 cords in the house, well over a 50% reduction.

How well it will work in a two-story house, I cannot say for sure, but going by my results, I expect you would take longer to heat your space; perhaps instead of one or two fires a day, you might need three or even four when the arctic blasts settle in.
After living my whole life with wood stoves that get lit in October and never are allowed to go completely out until April, having a masonry stove is beyond belief.
No fires all night, no fire most of the day... You can leave for all day, and the house is just as warm when you return as when you left.
You never need to worry about a chimney fire when you are sleeping, or not home, because there is no fire!

And then to put icing on the cake, there is NO creosote ever, only super fine fly ash in the firebox.
The bell/ stratifacation chamber takes years to build up enough ash to need to be cleaned out.