Mills use kilns at low heat to dry the moisture out of wood. Wood is commonly used for building; however, it is unsuitable when it contains moisture because it is less stable. Kilns have to be set on a low heat threshold for this use, otherwise there is risk of the wood burning. Lumber-drying kilns have various settings that control airflow, humidity and heat inside their chambers.
Kilns are often used in ceramic modeling to fire glazed finishes onto the materials. The high heat seals the surface of the material, which results in a shiny glazed finish. For a more mature finish, the ware is returned to a kiln on a low temperature after being glazed in a high-heat kiln. The low-heat kiln adds an extra layer to the glazed surface, although this process only works after the ware has been fired in a high-heat kiln.
Lusters are sometimes added to clay material to put a color finish on the product. These chemicals can be toxic in their raw chemical state. Furthermore, they can burn off or become unstable at higher temperatures, Therefore, it is necessary to heat luster chemical finishes on a low heat to allow them to dry safely.
Prior to firing material in a high-heat kiln, it may be necessary to pre-dry the ware. A low-heat kiln is often used to pre-dry material that is too wet. Firing wet material in a high temperature kiln can result in cracks or bubbles forming on the surface; therefore, a low-heat kiln is used first to dry the surface.