I want to create a 16” entrance to the front. I have standard bricks that I will be cutting into veneers to cover the dome. I could use those whole bricks as in the picture below, or I could use fire bricks and cover with veneers? Will firebrick instead of standard brick retain more heat in this case?
Using firebrick is preferred but not absolutely necessary. (I would, simply because the front plane is part of the oven cavity.) Using firebrick to close the front, and making your own splits to veneer it, is a very sound plan.
Firebrick adds some insulative value, though its primary job is to withstand the high heat and direct flame of your oven. It also stands up to the mechanical stress of wood, pizza peels, pans, and scrapers. It can handle rapid thermal changes, which you get when you start a new fire in your oven (or you incinerate that roast! ). It’s the right material to have at the opening, though again standard clay bricks MAY be used.
What you DO need to use is the same heat-resistant mortar that you used for the rest of the oven cavity and the brick frame.
To my mind, the 50 percent or so premium for that small quantity of additional firebrick is well worth it.
Thank you Matt, very insightful and makes sense. Those were my thoughts as well for functionality. Glad my head is in the right direction. Dome and back are finished, chimney is next. One heck of a project especially in humid 90 degree weather! Its been fun seeing it all come together. The high temp mortar is fun stuff, like playing with mud pies. : ) On my 3rd 100lb bag of silica sand!