In loving memory of Kenis D. Keathley 6/4/81 - 3/27/22 Loving father, husband, brother, friend and firewood hoarder Rest in peace, Dexterday

Redesigned my thermal mass

Discussion in 'The Wood Pile' started by Dunmyer mowing llc, Oct 26, 2025.

  1. Dunmyer mowing llc

    Dunmyer mowing llc

    Joined:
    Sep 26, 2023
    Messages:
    508
    Likes Received:
    3,376
    Location:
    Indiana
    Last season I experimented with thermal mass.
    Roughly 1500 lbs of cinder block.

    Alot of people on here told me it did nothing, waste of time, ect.

    It was good for about 5f gain average through the season.

    My thoughts on why it works for me are
    1 my house is old, big and drafty.
    If I'm pumping a bunch of heat into the air it gets "blown" out quickly.
    With the thermal mass it's radiating heat slowly so therefore it doesn't blow out as fast.

    2 I tend to be gone long amounts of time so I really stretch my reload times.
    The stone helps keep a little warmth on them long stretches.

    Anyway, I redesigned it for this season with the exact same things that were on it last year, but I gained my access to my stovetop back so I can cook on it again.
    Not sure if the fan will get enough heat up there to operate but we will find out soon IMG_20251026_165835.jpg IMG_20251026_165842.jpg IMG_20251026_165856.jpg
     
  2. JDU

    JDU

    Joined:
    Apr 29, 2016
    Messages:
    545
    Likes Received:
    4,531
    Location:
    Perry County, PA
    Interesting. You created somewhat similar setup to an insert in a fireplace, which is what I have. Should work OK for you if you liked how it performed last year. . Let us know.
     
  3. Dunmyer mowing llc

    Dunmyer mowing llc

    Joined:
    Sep 26, 2023
    Messages:
    508
    Likes Received:
    3,376
    Location:
    Indiana
    Actually found some more blocks from when I had to replace my sewer line.
    Guessing 20lbs each so another 100 of mass gonna burn a small fire tonight IMG_20251026_184541.jpg
     
  4. brenndatomu

    brenndatomu

    Joined:
    May 29, 2015
    Messages:
    23,408
    Likes Received:
    150,265
    Location:
    NE Ohio
    That's known as convective, vs radiant heat...with a drafty house, radiant heat would feel better.
     
  5. Dunmyer mowing llc

    Dunmyer mowing llc

    Joined:
    Sep 26, 2023
    Messages:
    508
    Likes Received:
    3,376
    Location:
    Indiana
    Convective being a stove that heats the air correct?

    Now we would see higher peak temps pre thermal mass, but this way it is a higher average temp inside the house
     
    eatonpcat and T.Jeff Veal like this.
  6. eatonpcat

    eatonpcat

    Joined:
    Oct 5, 2013
    Messages:
    9,686
    Likes Received:
    54,031
    Location:
    Eaton Township, OH
    I am trying to figure out what my wife would say if I stacked CMU around our stove!
     
    T.Jeff Veal, Ron T, jrider and 10 others like this.
  7. brenndatomu

    brenndatomu

    Joined:
    May 29, 2015
    Messages:
    23,408
    Likes Received:
    150,265
    Location:
    NE Ohio
    :heidi:
     
  8. brenndatomu

    brenndatomu

    Joined:
    May 29, 2015
    Messages:
    23,408
    Likes Received:
    150,265
    Location:
    NE Ohio
    Yes
     
  9. brenndatomu

    brenndatomu

    Joined:
    May 29, 2015
    Messages:
    23,408
    Likes Received:
    150,265
    Location:
    NE Ohio
  10. Eggshooterist

    Eggshooterist

    Joined:
    Dec 19, 2021
    Messages:
    6,580
    Likes Received:
    35,138
    Location:
    Erff
    I know what mine would say...
     
    T.Jeff Veal, Ron T, eatonpcat and 5 others like this.
  11. yooperdave

    yooperdave

    Joined:
    Jun 16, 2014
    Messages:
    34,275
    Likes Received:
    212,240
    Location:
    Michigan's U.P.

    Closing the front door that leads into the porch would help eliminate some of that drafty feeling also. :hair:

    Refer to the pics.....:whistle:
     
    T.Jeff Veal, Ron T, eatonpcat and 7 others like this.
  12. buZZsaw BRAD

    buZZsaw BRAD

    Joined:
    Feb 14, 2019
    Messages:
    32,607
    Likes Received:
    199,262
    Location:
    North Haven, Connecticut
    Try it out and let us know! :D
     
    T.Jeff Veal, Ron T, sms4life and 4 others like this.
  13. buZZsaw BRAD

    buZZsaw BRAD

    Joined:
    Feb 14, 2019
    Messages:
    32,607
    Likes Received:
    199,262
    Location:
    North Haven, Connecticut
    One of my customers has a Russian fireplace. Basically a wall of bricks where the exhaust smoke goes through the maze heating them up as it goes out. I had never seen or heard of one prior.
     
  14. brenndatomu

    brenndatomu

    Joined:
    May 29, 2015
    Messages:
    23,408
    Likes Received:
    150,265
    Location:
    NE Ohio
    They work really well, from what I hear
     
  15. chris

    chris

    Joined:
    Oct 9, 2013
    Messages:
    3,149
    Likes Received:
    11,150
    Location:
    SE WI
    there is a firm in the souther states that builds those Rump.... (I don't remember the rest of the spelling) type fireplaces. Homes with them are literally designed around the fireplace. They are massive- not something you want to try and float on a few 2x12s joists.
    With weight you are adding and have basement underneath, adding some suport pillars down there would be wise .
     
  16. Dunmyer mowing llc

    Dunmyer mowing llc

    Joined:
    Sep 26, 2023
    Messages:
    508
    Likes Received:
    3,376
    Location:
    Indiana
    I would think if Russians are good at anything it would be heating with wood
     
  17. Dunmyer mowing llc

    Dunmyer mowing llc

    Joined:
    Sep 26, 2023
    Messages:
    508
    Likes Received:
    3,376
    Location:
    Indiana
    The supports were the 1st thing I did.
    I got 3 of them down there
     
  18. ole

    ole

    Joined:
    Dec 5, 2015
    Messages:
    1,856
    Likes Received:
    15,632
    Location:
    Rock County Wisconsin
    or vodka
     
  19. buZZsaw BRAD

    buZZsaw BRAD

    Joined:
    Feb 14, 2019
    Messages:
    32,607
    Likes Received:
    199,262
    Location:
    North Haven, Connecticut
    LOL!!! :rofl: :lol:

    I thought the same thing! :drunk:
     
  20. Dunmyer mowing llc

    Dunmyer mowing llc

    Joined:
    Sep 26, 2023
    Messages:
    508
    Likes Received:
    3,376
    Location:
    Indiana
    Ahh yeah I forgot vodka, AK-47, sks ,tiger tanks,

    If not for the whole communist thing I could be happy as a Russian.
    As long as they allow beer to