What size work do you produce? Will the size of individual pieces require a kiln of a certain width or height?How much work do you produce? Will you frequently need to fire fifty or more pieces at a time?What temperature range do you want to be able to fire to? Do you work exclusively in low-fire earthenware or in high-fire stoneware?Do you need a kiln that is easily capable of both oxidation and reduction atmospheres? What atmosphere do the clay body and glazes that you want to use require?
It’s now time to begin weighing your options. What energy sources are readily available to your studio?
What is your electrical service? Electric kiln power usage is complicated. Find out more: Electric Kiln Basics. Also take into account other electrical needs (e.g. potter’s wheels, blowers and ventilation system). Do you have natural gas lines in your area? Will the pressure be adequate? Do you have a propane tank? How large is it? Are you prepared for the intense physical challenge of firing with wood?
Most older electric kilns only have two to two and a half inches of insulation, generally in the form of soft firebrick. This is really not sufficient; the kilns lose a lot of heat, which also means higher firing costs. Some newer models of kilns have three and three and a half inches of insulation (soft firebrick and ceramic fiber blankets). These kilns, with their added insulation, are much more energy efficient. Don’t forget that as important wall insulation is, the insulation of floors, ceilings, lids, and doors needs to be just as good. Kilns need a minimum of one and a half feet of air space around their sides. Commercially built kilns almost always come with clearance space under the floor of the kiln, as well. If you are building your kiln, the floor must be thick enough to stop any heat leakage. If the kiln will be located indoors, more clearance is needed overhead. Even with overhead ventilation, four feet or more of space is a good idea. Evaluate the space you have available in light of the above considerations. It may be helpful to request the manufacturers’ installation instructions for kilns you are considering. Double-check and be certain that you will be in compliance with all applicable regulations and restrictions before you buy your kiln. Make sure you understand how this kiln works and that you will be able to work with it. If you have any questions, ask the dealer’s or manufacturer’s customer service representative. A further suggestion: Once you have purchased your kiln, make one or more copies of the owner’s manual. Make notes on the copy and keep these updated. This will help you learn and keep track of your particular kiln’s quirks.