Sunday, January 29, 2012

Masonry Heater Part III: A Finished Finnish

My 22" finnish contraflow heater core is finished. It probably isn't precision perfect, but considering I had never laid a brick before in my life; I'm pretty pleased with the outcome. The pictures below are my course by course outline (save for a couple courses I forgot to photograph).

I decided after I had the corners of the transition header in place, I would mortar four of the bricks together before I put them up. It worked fairly well except I was getting to the bottom of my mortar and a few hard chucks of mortar threw a couple bricks off kilter. Lesson learned.
Header bricks in place.
I only did a course by course of one side channel since they are both the same. This is the left side channel finished. It is worth mentioning that I used mineral wool on one side and ceramic paper on the other side. There were pros and cons of each, but overall I would probably use the ceramic paper again if it is available.
Course by course of the right side channel (ceramic wool gasket - 2 thicknesses of 1/8" paper).
This is a picture of the bond pattern. Each course contained a 4 3/4", 3 1/8", 3 3/8" and 2 full bricks.
1/8" ceramic paper gasket on the top. The pre cast capping slabs go on next. We did get them on with only two people but a third person would have been nice.
Capping slabs in place. Voila! Remember when I said that a couple transition header bricks got a little kittywampus. Those rogue bricks made it so the slabs had some air gaps in some locations. I remedied the situation by stuffing in chunks of mineral wool.
You can see the unevenness of the header bricks in this picture.
The ratchet strap was put on so the side channels wouldn't move while we were putting on the capping slabs. The side channels sit dry up against the ceramic paper gasket.

Now I just need to figure out the chimney and put the facing on. Excitement ensues!


  1. It's been very neat to watch this go up. Thanks for posting.

  2. Hi Jared... I am really enjoying your blog and great project, good job! I was wondering if there was a way to contact you privately - I can't seem to find an obvious one here? You can send me a message via


  3. I am so impressed with not only your building of a masonry heater, but your excellent documentation!! I am planning on starting this exact heater shortly...I was so excited when I ran across your blog. This is the best tutorial, yet. Thanks so much! Once I get started on our project, if we get stuck, would you mind us contacting you and quizzing you? Your heater looks quite excellent.

  4. Thanks for posting. I keep an eye for your work, I'm from Moscow (Russia).
    To be continued?

  5. Masonry Heater Part III: A Finished Finnish. My 22" finnish contraflow heater core is finished. ...