35'Diameter, 2 level/story, Half Sphere Dome In Canada



  • I have so many questions but, I will limit them to a few for now. The easiest to start with is, has anyone built a dome around 35 feet in diameter and 17.5 feet high? Our thought is to build a free standing (not reliant on the dome to support the weight) log structure within the dome to build a second story for the home. We are also in Eastern Canada and have extreme cold in winters. What would the minimum thickness of the walls need to be for proper insulating factors as well as snow load? I was thinking 6 inches would be enough but wondered if they should be 8 inches..? Thoughts, concerns, questions, and gentle ridicule would all be appreciated. I am in love with this concept of building and the work that everyone is putting into this community.

    PS Is there any advantages/disadvantages to building in the shape of Dome Gaia style versus a half sphere? Thanking you all in advance.



  • @Kintore I’m looking forward to the replies on this one. A ten metre dome is something I too have been considering. In my case, the insulation is for the extreme heat of Australia, but the same logic applies.



  • Hello Kintore I am trying to build a 24' base dome on Vancouver Island but am having a major issue getting a building permit. They want an engineers approval of the drawings before they will accept it. Good Luck. Bob



  • Do none of the experts have any advise or opinions on this?



  • Has anyone heard anything outside of this thread?
    I'm in Alberta and very interested in how other people are doing this in Canada.



  • Hello Kintore I am attempting to build a 24' dome using a one foot off set which will give me about a 18' height. I am building a 3 1/2" wall thickness and after seeing a video with a blowtorch on one side and after an hour he could touch the other side without feeling much heat. Therefore I am thinking that even 3 1/2" thickness will be warm enough for my Victoria area. I will be building a second story in my dome. I have been trying for eight months to get a building permit. I have at last found an architect that will prepare an "Alternate Solution" report that will enable a building permit to be issued. It will cost me $3540.00.



  • @Kintore I am trying to find studies with specifications on this. Heard there are tests that have been done way back in the 70s & 80s but I have not yet been able to access them. Think it was here: https://www.astm.org/ABOUT/overview.html

    I also found a video of a home in Canada but don't think it used aircrete. Just straight concrete. Maybe this will help too. https://youtu.be/RoGuvvzHY1A
    It is a beautiful structure. Have to really listen for the tid bits of information like I think she says the walls are 4in thick. Inside is coated with powdered marble. You DEFINITELY want to check out the "fridge". Brilliant.



  • @cjanelle recently found this video. Maybe you could follow up on it. Youtube Video



  • I'm sorry to say I don't think anyone is going to give a permit for aircrete here. And an enginner sign off will be required. That said, perhaps everyone wanting this might pool together and hire an enginner to sign off on a plan that could then be used by all? Simmilar to what they did with earthships.



  • @ormom8 I am in Victoria BC and I have an architect that is preparing a "Alternative Solution" for the CRD building inspectors and I am expecting my building permit any day now.
    Bob


  • Workshop Instructor

    Domie,
    The only way to make it code compliant is to use a structural technique that has been approved and used. If we treat the aircrete dome as "insulation" and not structural- even though it is- maybe there is a way an engineer will stamp it. See ferrocement techniques...

    As for 35 feet, I don't see why not. At that width and heigth though you are going to have a harder time heating it. If you are going through with it, I would consider a cantenary dome, it will resist snow loads better, shed water and snow faster, and have less hoop stress. And as for insulation, the thicker the brick, the better insulation. Also, have you thought of applying thermal mass? It helps allot in cold environments. Check out Earthships for their systems of heating and cooling passively, and Earthbags for retaining walls...There is allot to research it seems before you wanna break ground. I am available for consultation, build, or training. Goodluck!



  • @Ignacio-DHOME
    Someone took the time write an entire webpage on how this thermal mass doesn't work in Canada. https://www.ecohome.net/guides/1161/do-earthships-work-in-cold-climates/
    I'm not sure what they get out of this lie. It totally works here and we have serveral earthship in the northern parts even that are almost completely passive heated in extreamly cold weather i've seen people growing bannana and avocato trees. So yeah. I agree adding thermal mass up here is a great idea. I also think the thermal mass should not be exposed to the cold. I'm so busy with my aircrete panels at the moment but next summer, I'm going to make aircrete tire bricks and fill the tire with aircrete instead of rammed earth. And build an earthship with them. then put the thermal mass on the INSIDE of the tires and the south facing glass. As for coding. no idea. maybe i'll cover the whole thing with pine branches so no one sees it. lol. Just kidding.. kinda.



  • @rloten Do you think you could resell this plan and other building inspectors from other provinces would accept it? An architect isn't an engineer. Not that I don't respect them, but i'm always told an engineer needs to stamp it.



  • In Victoria the Building Inspectors "Alternative Solution" has to have the drawings stamped by an engineer or and architect.



  • @Kintore Hi, imagine you are in a hemisphere and walk towards the perimeter. How close can you get before bumping your head. This is one of the biggest benefits of the Domegaia solution - you gain all that space under the curve. The other benefit is aesthetic - it looks beaut!


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