Kiln furniture is the shelves, posts and stilts used to stack pottery in a kiln. Shelves hold the work in layers, posts set the gaps between shelves, and stilts or cookies support pieces that need lifting off a shelf.
What Is Kiln Furniture?
Shelves are usually made of cordierite, silicon carbide or similar refractory materials that can carry heavy loads at high temperatures without sagging. They are coated with kiln wash on the top surface so drips of glaze can be chipped off rather than fusing to the shelf.
Posts come in a range of heights so you can stack short and tall pieces efficiently. Most potters use three posts per shelf, which sits steadily even if the posts are slightly uneven, and line posts up directly above each other through the stack so the load passes straight down.
Furniture takes up a surprising share of a kiln’s space and adds to the heat the kiln must absorb, so planning the load matters. Cracked shelves should be retired, as they can fail mid-firing and drop the whole layer. Thick, heavy shelves can also hold heat and slow cooling, which affects how work near them fires.
This pottery glossary entry from Le Studio Art Space is general educational content. Always follow the clay, glaze and kiln makers’ data for your own materials and equipment.