building pizza oven with used bricks

[cheesel0vers]

I noticed that people are selling used bricks. they're ofc cheaper than the new bricks, and I'm interested buying them to build a pizza oven
I'm thinking about mixing the fire and non fire bricks, but kinda concern about the safety
is there gonna be toxic material in it, or is it safe to use them to build an oven?
thoughts?

 

[JoePizza]

Use fire brick for the oven and regular bricks for the facade.
The regular brick will crack apart under high heat.

 

[CleanSlate]

Used bricks are fine as long as you are careful where you use them. Regular reclaimed bricks are safe for the outer structure, but they’re not made to handle high heat and can crack or spall if used in the firebox. For the cooking chamber and anything in direct flame contact, you really want proper firebricks. Mixing them is common and safe if firebricks line the inside and reclaimed bricks stay on the outside. The main risk isn’t toxicity, it is heat failure.