Aircrete for a wood-fired oven? Silly idea?



  • Hello,

    New here and recently learning about AirCrete. I apologize in advance if I'm not posting to the correct forum.

    I'd like to use AirCrete to form arch bricks and regular bricks for the arch roof and side of an outdoor oven. If light enough, I may consider making the arch roof in AirCrete sections...

    Would this be feasible with AirCrete? My concerns are:

    • Insulation - will it trap heat or dissipate through the aircrete?
    • Toxic when heated? The floor will be pizza stone tiles on top of aircrete blocks.
    • Will it hold up to multiple firings... I live in an area that gets all four seasons.
    • Do I need to consider refractory cement? The wood fire should only reach temps of ~1000F (550C)

    Thanks in advance!
    Ken


  • Little Dragon Tamer

    Ken, welcome. I'd say you chose the correct category for this topic. I have no personal experience making an outdoor oven using aircrete, but it seems to me like a great idea.

    Is aircrete insulative? Quite. Aircrete consists of up to 75% or more trapped air pockets by volume depending on how it's made.
    Toxic when heated? Don't think so. Aircrete uses some dishsoap to create the foam, but it's mostly cement and air. Is cement toxic when heated? Naw. Chemically very stable at those temperatures.
    Multiple firings in all seasons? I bet $25 that a decently made aircrete outdoor oven would handle all that without cracking due to firings or weather.

    To be clear, this is not advice from an expert, but encouragement from an enthusiast. I'm planning to make a small oven cooker hotbox using aircrete for making soup in a 6 gallon pot. My plan is to encase the pot with about 3" of aircrete and install an electric burner at the bottom. If you execute your plan, please document the process and keep us updated! I'll do the same.



  • Thanks for the encouragement. Its enough to push the needle to the "Ask the wife for permission" stage.

    I've got some ideas in CAD software, so its just matter of building the forms and trying a few blocks. If it gets beyond that, I'll be sure to document.

    Thanks again along with the nice welcome. I'm sure I'll be back to read up on ideas for AirCrete formulation.

    Ken


  • Major Contributor

    @kcc703 look for aircrete and rocket stove on the net.



  • @zander Sounds like you just made a crock pot! Any photos yet?!



  • @KCC703 my so and I made an aircrete pizza oven. It works - keep feeding the wood and keep making pizzas - but not well. Aircrete is a great heat insulator so it keeps the heat in the oven. The aircrete doesn’t hold the heat which means the oven starts cooling as soon as you stop burning wood.
    So you can’t fire up the pizza oven, cook a round of pizzas, then pop in a loaf of bread and a roast, followed by pud, cakes and biscuits - ie heat the oven and then use the heat for different foods as it cools.
    We intend to knock down and do it again with the oven lined with refractory bricks and aircrete covering that


  • Workshop Instructor

    @KCC703
    Use cob instead. Better thermal.mass... Insulation may not be what you want. Also, yes, I would be concerned with offgassing of concrete...


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