Here are some of the considerations for buying a kiln. Certainly the size, the electrical characteristics and how that affects you, the width and the height of the chamber. The first major factor is cost. In modern societies pottery and brick is fired at kilns to temperatures ranging from 1800 Fahrenheit to 2400 Fahrenheit. Most of the common glaze like the clay found in our backyards start to deform and melt if they are fired higher than about 1900Â°F modern toilets are fired from clay that has fewer contaminants. Ceramics require heat at high temperatures so that physical and chemical reactions will permanently alter the unfired body, clay material. Play materials are shaped on a wheel or by hand prior to placing in the kiln. Often paint or glazes are applied to the unfinished pottery item. The first firing is called a bisque firing were the newly formed item is placed in the kiln and fired. It is important that the pottery is dry. The kiln is loaded. Once a bisque firing is complete the pieces is more stable and harder. Often after the first firing the piece is glazed or painted.