For most people, making a home blast furnace or pizza oven seems simple. Just put together something that can withstand heat, make sure that it is the right size and shape, and go to town. However, this can be dangerous and may actually make it more expensive to operate these overs and furnaces in the long run. This is because most basic materials that can withstand heat are not actually meant to be used in these processes, but will simply stand them for the time being, releasing heat as they work.
You need to look for a material that will keep heat in, and possibly even reflect it to increase the temperature. This will in turn make it so that the fire uses less fuel, heats up faster, and burns at a more consistent temperature.
You also need to look for a material that is going to last a long time. While there are a number of options available that will hold up for a few years, replacing all of your stoneware after a few years is a hassle that you don’t actually need to undergo. Instead, you can get bricks that will last at least 10 years if not 20. In some cases they last 50 or more years, even with heavy usage.
Finally, you need to pick a firebrick that is going to be easy to clean and easy to work with. This will reduce the amount of time needed to create your furnace or oven, but will also allow you to keep it in the best shape possible.
Thankfully, there is a product known as insulating fire brick that can meet all of these requirements and that is rather cheap. You can find it online or in most home improvement stores as well.