Corsair's 42" Pompeii Oven Mk 2

[Corsairmo]

Thanks UtahBeehiver, how long does it take for your oven to heat up? And how much wood would a firing take? My light duty oven took about 30-40 mins to heat up and I'd use say a milk crate worth of logs per firing. I'm worried it will take much longer with the heavy duty bricks, thus me considering cutting down the bricks.

[RandyJ]

My first oven was built out of super duty bricks. It worked great. It did take quite a bit of wood to get up to temp though. As for blades I used 10" segmented blades from Rigid and completely burned up 3 and made it a good way into a 4th. Just for your information.

Randy

[Corsairmo]

Did I render out the dome and the floor ahead of picking up the second load of bricks because I am excited for this find? Yes I did! Did I do some calculations and determine I want to cut the bricks down to 3" depth for what I hope will be a good balance of thermal mass and a responsive heating time? Yes, I did! I'm particularly excited about the curving floor bricks (background rendering), I think they will be eye-catching without being peel-catching!

[Corsairmo]

After exploring a number of ideas I think my wife and I have settled on a bold idea for the design of the pizza oven.

The oven would be a normal 42" oven, with the regular woven insulation blanket around it etc. But I want to construct it as a tower-style structure as seen in these inspiration pictured attached below. My thinking is to form a columnar shaped vermicu-crete shape on top of the dome, and then add a waterproof lid (and down the sides, I am thinking waterproof coating and plastic sheeting) so that on top I can plant vines and such to grow to adorn the outside.
I know this may present some careful consideration in the curing and drying phase of the oven to make sure all the moisture is driven out of the oven, because I don't want to entrap any excess moisture before sealing it over. However, once fully cured, my original oven showed no steam cracking or other issues over the years, despite being built on the wet Oregon Coast and not being terribly well-protected from the weather. Does that align with other's experiences?
Additionally I will have to figure out a suitable way to drain the soil on top of the oven such that it doesn't affect the oven's performance. I think a spout as pictured, or multiple drilled or inserted narrow channels should divert water away from the lower oven.
Are their other design considerations I might be missing? Tell me what I am not thinking about in this early design stage!

[UtahBeehiver]

Very interesting, the key will be to ensure that the roof is waterproof so water does not get into the vcrete or ceramic blanket. The v/pcrete will need to be more structural than insulating since it will be support the roof and soil, ie 5 to 1 ratio may be a good start. See attached table.

[Corsairmo]

I plan on using 3" of ceramic blanket, so I'm not too worried about the insulated properties of the vcrete, but I am worried about compressing the blanket with the weight of the soil. I've been thinking about if I could run some metal strapping anchored to the external facade to help bear the weight of the soil instead of just the vcrete. I've seen others on the forum use what I believe is some sort of paintable latex sealant on top of a stuccoed vcrete; which I would do along with an added layer of black plastic to doubly ensure water imperviousness.