Collapsing forms remedy- warm water


  • Workshop Instructor

    Hello Domies.
    I wanted to share something We discovered regarding some collapsing forms at the Port Townshend Washington workshop. We found that in cold weather it helps to use warm water in your cement mixes. Warm water helps the cement set up faster keeping the foam intact and the aircrete from collapsing. Also, if you are having collapsing forms even in warm weather, try changing your dish soap. 7th Generation is not always the most reliable it seems. It is a plant based soap which is great for the environment, but at times not great for making aircrete brownies!


  • Little Dragon Tamer Workshop Graduate

    Thank you for the super info Ignacio



  • Hi Ignacio,
    We are building an aircrete dome in France. Winter is starting and it's now less than 10 ℃. Today, for the first time, our forms collapse.. We try to add hot water with the cement mix but it didn't change anything. Can we add hot water with the foam mix ? Do you have any other idea ?!
    Thank you 🙏



  • @Carolebrdn yes! Try using hot water in the foam mix. This is what we did at the Pt Townsend workshop and it seemed to have success. They had trouble later keeping the water warm, so I think they got an electric water heater like the link below to keep the foam mix warm. You could also keep the foam mix circulating by using the little dragon without any air on and just putting the outlet of the pump back into the top of the barrel. This circulation generates some heat in the foam mix from friction in the movement.

    Farm Innovators Model H-419 Ice Chaser Cast Aluminum Submergible Tank De-Icer, 1,500-Watt https://www.amazon.com/dp/B000HHO9LC/ref=cm_sw_r_cp_apa_i_DXbZDbTD8S5Q6


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