Wednesday, October 31, 2012

Masonry Heater Facing

We have finally finished facing our heater. We faced it with Brampton bricks from Hebron Brick. I like that our bricks came from just down the road a spell, even though my original hope was to find reclaimed bricks.

I don't have a lot of expert tips on slinging mud and laying bricks, since before this project I had never laid a brick. However, I do have some tips for beginners like me.

We set plumb lines for the corners, because I saw that most professionals do this. In order to set them I borrowed a laser plumb line from a friend of mine. It worked excellent and saved us a lot of time.

If you have never done any masonry before, make sure you have a wife that is willing to tool all the joints. My wife is good at it and hides a lot of my mistakes.

Tips specific to this heater.
My hardware came from Northstone Heat. Their customer service is top notch! Our hardware installation came with a learning curve. Our firebox door said for a 410 x 410mm door, you need a 420 x 420mm rough opening (approx. 16.5"). I would have gone with 17" x 17" if I were to do it again. The frame of the hardware would more than cover the gap and it would have made them easier to install and gave us more room for an expansion joint. We installed ours using the hammer drill and screws supplied with the doors.

We did the jack arch based on Marcus Flynn's description.  My Dad did an excellent job of drawing the template for us. I used the cardboard template to cut the bricks with a diamond blade on my miter saw. Even though it is an arch, we still opted for a steel lintel for peace of mind. I lined the lintel with ceramic paper in order to block some of the heat.

We chose to wrap the core of our heater with fiberglass for an expansion/slip joint. Some masons use cardboard but fiberglass seemed more professional to me. We used fiberglass mat that you can buy at auto parts stores. It is normally used for bondo work. It worked OK but it only came in 8 square foot pieces. It wasn't until we had already wrapped it that we found out there is a shop in town that repairs fiberglass boats and would have sold it to us off of a roll. So, look for boat shops near by. The front and back (where it is hottest) got four layers. The sides only got one. I also put an additional piece of ceramic paper above the firebox door (not seen in picture, sorry) to try to keep the mortar from cracking in a spot that will see a lot of heat.

We haven't been able to fire it yet, since we have to install the chimney now. Winter is coming and we have a large stack of firewood just begging for flame.


  1. Gorgeous, gorgeous, gorgeous!!! I am so impressed with you and your wife's work! Let us know how it works once it is up and running....

  2. Thanks! You are too kind. This weekend we popped the chimney through the roof (not fun) and we are now bringing the heater up to temperature. Just in time it is only 8 degrees this morning! Stay tuned for the blog post complete with fire pics.

  3. Oh I miss our masonry heater that we built back in our Wisconsin house - you will be able to do amazing things with that oven besides the usual pizza and bread - one year I even made a duck for Christmas! Congrats, its beautiful, you did good!

  4. I'm very excited to start cooking with it. Was it hard to learn how to use the bake oven? Timing and temperature and such.

  5. I like this lovely photo of masonry samples, keep up the good work actually with this I remember the blog of Masonry in Washington DC.

  6. Dear Jared,

    bravo, very inspirational! I am planning to build same 22" core according to MHA plans in next few months in our new house and I have some questions to you regarding your experiences by building and using of masonry heater (first of all sorry for my English... :-) ). Your work seems beautiful! There is no tradition in building this type of heaters in our country, so for me is very helpfull every information. (in middle Europa are mostly build heaters type like "Kacheloffen, Grundofen" atc...same principle of heat accumulation but totally different construction/design.
    1. You built supplementary under air intake in core right above ash doors like it is described in article from Marcus Flynn. Is it working in reality? Burn embers more rapidly on the end of burning process with this option? Technical question: In article from Marcus is written " the opening for the ash box must be precise to prevent over air running through it and becoming under air" How did you achieved it? The design of core from MHA portfolio is for under air so make sense to add additional under air opening?
    2. Did you recognised some necessity of additional air supply from outside (exterior air intake) during using of heater, or there is enough air in rooms available for burning process (no underpressure)?
    3. It seems, that your hardware is from Finnish producer Pisla Oy...are you satisfied with them? Will you recommanded this hardware?
    4. What distance let you between core and facing? 1"? Did you fill it with normal mortar used by facing or some dry mixture?
    5. Did you cast base slab only with vermiculite and pure portalnd cement? No additional mixture?


    Peter, Slovakia

  7. Jared,
    Guess what?! We fired our masonry heater for the first time on Saturday! Way back when, you were kind enough to answer any and all questions that I had about building a heater. If it weren't for your wonderful documentation of your heater, I would never have been gutsy enough to give ours a try. Thank you SO much. Your generosity and knowledge were/are greatly appreciated!

    I still have to put some finishing touches on the heater, but it is functional and doing its job.
    Thanks again:)

  8. That is great news! Do you have pictures online that I could take a peek at?

  9. How is your heater working for you? We are still in the sketch stage of our slipform masonry home and I'm hoping to avoid a "great room". Does it seem to heat/reach everywhere, or do you find you need backup?

  10. We are very happy with it. For us it is centrally located in a small well insulated house. We fire it twice a day unless it is extremely cold and windy, then we might add a small third fire. If it is above 30 degrees F outside we will only do one fire. I hope this helps!