foundation size for 42 pompeii oven? who knows?

[jdefeo]

I'm about to build a pompeii oven 42 inches, using the free directions download. p. 13 says the foundation should be 73 X 86. The Materials list on p.66 says the foundaton should be 80 X 94. Any idea which it should be?

having to dig down 42 inches below the frost line, I'd appreciate the help. Lot's of dirt flying over here.

[FrankT]

I say calculate how big you want your block stand then add 4" all around.

For reference;
My foundation slab is 7'-4"d x 6'-8"w my stand is 4-1/2 courses x 5 courses and my oven 42" inside diameter...

[GianniFocaccia]

It might help to look at your project from the inside out. Start with your 42" diameter floor and add 9" for firebrick halves (51" total). Calculate the thickness of your total dome insulation (3" ceramic and 4" vermicrete?). Now you can effectively plan for a support slab that will accomodate either an igloo or a framed oven housing, your choice.

[Neil2]

Why are you going down 4 feet with the foundation ? Do you have very poor soil conditions ?.

[C5dad]

I would also add 1 layer of cinder blocks to a total of 5 high. Looking at my oven, I will be stooping over a bit. C'est la vis

[jdefeo]

Thanks all.
We ended up with a 75 X 88 foundation and block stand of 65 X 78 as the directions say. I'm using 10 inch blocks to get to ground level (4 courses) then will switch to 6 inch blocks to get up to our deck (about 8-9 courses). We went 42 inches into the ground to get below the frost line in CT. I don't think it will be going anywhere soon.

[GianniFocaccia]

I think most builders plan for a final oven floor height approximately the distance from their elbow to the floor they are standing on. This is so they don't have to stoop over to see or move the pizzas in the oven.