Steel deck for oven

[Bigtulk]

Hey there I'm nee to the forums but looking for some help. I'm building an oven out of an old propane tank. So I used the end of the tank with the dome. I'm planning on a 1/2" thick steel deck and wondering if under that I should use a 2.5" fire brick to insulate and help hold the heat or if a half brick would be fine or no brick at all and just use insulation. Open to your thoughts and thanks for the help.

Tulk

[wotavidone]

Steel has a density of around 8000 kg/m3

Brick has a density around 2400 kg/m3

So your 1/2" steel floor is about as heavy as just over 1 & 1/2 inches of fire brick.
Consider just using insulation under the floor.

[Bigtulk]

So you dont think I need to use brick under the deck? The dome is prob 3/8 or 5/16 thick I was planning on using 1.25" brick on the outside of the dome them covering in insulation as well. Do you think that is enough or to much?

[UtahBeehiver]

We periodically have a discussion about using steel as the dome material. Here is a link to one we had recently.

https://community.fornobravo.com/for...ome-insulation

[wotavidone]

So you dont think I need to use brick under the deck? The dome is prob 3/8 or 5/16 thick I was planning on using 1.25" brick on the outside of the dome them covering in insulation as well. Do you think that is enough or to much?

My thoughts:
Mass is mass - 1/2 inch of steel is as much mass as 1.5 inches or so of brick. But - it will conduct the heat away more than brick will, so you need to be very well insulated, and it will conduct heat into the pizza more than brick, so you stand more chance of burning the pizza. There's a reason the very best Italian ovens use clay tile - more suitable conductivity, plus a little porous helps with moisture control.
Considering the oven you are building, you no doubt need the steel as a structural element to support/provide your cooking surface. If I was doing it, I would use the steel purely for structure and put your 1.25" bricks on top for the cooking surface. Then insulate, insulate, insulate.
It would mean you'd have the equivalent of nearly 3 inches of brick on the floor which is a lot but not so uncommon on this forum. Might even make sense to source 2 inch bricks for the floor and put insulation between the bricks and the steel. My mates oven has 3 inch brick floor though. (Fired clay pavers - less dense than fire brick.