There’s an old saying – you can never have too much insulation. It’s true for brick ovens too. Don’t be fooled by models that have a steel roof. It is literally a radiator releasing most of the heat from the top of the oven. Thermal mass is good for cookers, and steel also burns out very quickly at temperatures above 700F, particularly in a wood burning environment. A good oven should maintain below 300F around the outside of the oven (a difference of 900F from the internal dome!) in order to keep up. Any additional insulation beyond that has the benefit of shortening heat up time, reducing fuel usage, and keeping the oven hot longer.
How They Work
Brick ovens cook not only hotter than just about any other cooker, with parts of the oven around 1200F, they also cook with all 3 primary types of heat at once (conduction, convection, and radiation). A proper brick oven therefore needs – a thermal mass and properly conductive surface for the pizza to sit on (the floor or a pizza stone), 2) a structure that encourages convection, which, as it turns out, is a dome, with a chimney approximately 0.63. For the radiation, and dome is also ideal, particularly when the fire is burning directly below.
Once you have these things, if you can fit a fire big enough to fit it and your pizza and maintain an 800F floor and a 1200F dome, then you are in good shape.
A good oven needs an opening in the front. A hinged lid doesn’t really allow for proper air flow and physical access is obviously made more difficult.
A good oven has to do all of the above, and we’ve designed our to also be durable, lightweight, modular and portable.