I have seen this discussion on thermal mass on another forum a few weeks ago and there was people saying it did not work. I do not mean to slight anyone on here by saying this, but it really takes a lot of mass...hence the name...a hundred pounds just is not going to show much in the way of improvement. I did not realize how much rock I had hauled in until I dismantled the stove and removed the rock that Spring to be honest with everyone. BUT I live on a concrete slab so weight is not an issue. With a stove on a wood framed floor, doing this might mean a lot of bracing from underneath. I probably have a picture somewhere, but it was when our house was being remodeled so I would be embarrassed at what it looked like.
Fabz your description of the stove and the mass resemble that of a rocket stove. There is a subforum for and if I recall correctly BrianK and Eric VW are proponents of. Brian having started a company designing them.
It’s kind of a hybrid that allows access to the stove ... if you wanted to go to the extreme you could encase the stove in Adobe and it would most definitely increase the performance .... the main reason I did what I did was to even the temperature swings and extend the burn time
There's at least 1500lbs of thermal mass here, and I gotta tell you that rock radiates heat a long time after the stove dies down.
When I get the stock I’m going to weld up some water tight stainless steel boxes and fill with water ... 100 gal on a side for 200 gal total ... 200x8 = 1600lbs of thermal mass ... if I can get them to 130 degrees and want 65 temp then the difference is 65 ... 1600x65= 104000 btu stored ... may take a full day of burning but in this cold I’m 24/7 ... only drawback is starting from scratch with a cold stove !
Huge heat sink when starting from cold but likely no different from any other thermal mass. Any concern with excessive humidity levels?
Excess humidity would be tough to achieve when it is -2 outside. When it is cold my humidity is always too low no matter what I do.
The rocket heater subforum is at Rocket Stoves & Rocket Mass Heaters I’m currently designing one for in front of the family room fireplace in the basement. It will have about 2000lbs in a masonry bench connected to the rocket heater. They are awesome heating stoves where it’s possible to build a mass bench (or “bell” in rocket mass heaters and Russian masonry heaters terminology) but otherwise is just a clean efficient but short burn time space heater. You need the mass to absorb the heat then give it off after the short hot fires in a rocket stove go out. I planned and helped build this one a couple weeks ago in North Carolina. It has more than 5000lbs in masonry mass:
I put in a new stove in our house yesterday, although it was just a wall oven. I mentioned she should model in front of it, but she said she had " no guarantee where the pictures would end up". I said, "true, but I know it doesn't bother you". She blushed, but never disagreed with me! There was a woman on another forum that was a lot like Katie in that she dabbled as a model in earlier years. They were discussing how some people thought Rocket Mass Stoves were ugly so her and her friend set out to change it. She ended up modeling on top of the bench, but no Little Red Dress...in fact no dress at all!
She has blue ones too! (LOL) As a side note: I looked in pictures of the kids birthday parties and everything, and there was no real good pictures of what I did to get some thermal mass for my stove unfortunately.
It is a great center piece and I will love do something like that when and if I build. To my knowledge the basement level is only support for the upper two levels. There may have been some kind of a clean out down there but don't quote me. It's been a few years since I was there and only seen the lowest level once.
