Kiln Buying Guide
A kiln is one of the most expensive and important purchases a ceramic artist will make. Buying the wrong kiln can cost you hundreds of dollars and cause years of headaches. Here's what to look for when selecting a kiln:
Size
Don't buy the kiln you need now- buy the kiln you'll need in the future. A properly maintained kiln should last 20-30 years in a home studio, 15-20 years in a school or commercial studio. The amount of pottery you are making now will likely increase as you get better at it, so plan for the volume and size of work you will be making in 10 years. Do you dream of making really tall pots? Then don't buy a short kiln just because it's what you can afford right now. Save up for the larger kiln. It will be worth the wait.
Venting
Your kiln must be vented if it will be set up in an area where you need to breathe. The only time you can really get away without venting is if the kiln is in the garage, and you can fire with the garage door open. Any kiln in a house or studio must be vented. Downdraft vents are the best at removing fumes from the kiln, because they pull directly from the kiln. They are easy to install, and last many years. List price for a vent is around $425.
An overhead hood is another option for venting, however they are not generally as good at removing fumes as a downdraft vent, because the fumes must first come out of the kiln before they can be removed by the hood. Hoods are preferred in some situations, though, because they can also remove the waste heat coming off the kiln. Rooms with fire sprinklers (like at schools) will generally need a hood. Even a small kiln can heat up a room quite a bit. There are small, single-kiln style hoods on the market, but most schools will have an HVAC contractor build a custom hood that can be configured to the kiln room.
Location
Kilns are a fire hazard, and should only be set up on a non-combustible floor, like concrete. If you absolutely have to set it up on a surface other than concrete, put down 2 layers of cement tile backer board under the kiln. I recommend this for tile floors, too, because you never know what's under the tile. The more layers of protection the better.
Don't set your kiln too close to the wall. Recommended clearances will vary by manufacturer, but a good rule of thumb is no less than 18" from any combustible wall (drywall), and no less than 12" from any cement or stone wall. These clearances also apply to any furniture or shelving in the kiln area, not just the walls.
Maintenance Costs
Don't just consider price when buying a kiln. Consider how much it will cost to maintain the kiln for the next 20 years. The bulk of your maintenance costs will come from replacing elements. Depending on the size and brand of your kiln, the price for new elements can vary drastically. For instance, elements for a 27" diameter by 28" tall kiln average about $48 each. Some brands, however, charge as much as $90. That's a difference of $252 per set of elements. If you need elements every 2 years, that's $2520 over the 20 year life of the kiln.
If you're not comfortable changing the elements yourself, you'll need to pay a kiln technician to do the work. Most brands will require about 3 hours labor to change the elements on a 28" kiln. Others (L&L) will only take about an hour. At $75 per hour, that's a $1500 difference over the life of the kiln. Together, you can save over $4000 dollars in maintenance costs by buying the right kiln. That's the price of another kiln, with shelves and a vent!
Electrical Service
After you've decided what size kiln you'll need, you'll have to make sure your studio has the electrical service to support it. Kilns use a lot of electricity- far more than most other appliances in your home. The amount of power required to run a kiln is measured in Amperage (amps). The larger the kiln, the more amps it will need. Most small (18") kilns will require a 30 amp breaker. Most larger kilns (23" and 27") will require a 60 amp breaker or larger. Depending on the electrical service in your building, you may or may not be able to run a larger kiln. While most newer houses have 200 amp service and can handle a 60 amp kiln, many older homes only have 100 amp service. You'll need to have an electrician check out your breaker panel and see if you can hook up the kiln you want to purchase.
Along with the amps available in your building, your electrician should also check the service voltage and phase. Most buildings are wired with either 240 or 208 volts, and either single or 3 phase service. Most homes in the U.S. are wired with 240 volt, single phase service. Have your electrician verify what service you have, because your kiln will have to be wired to work with the electrical service in your studio. You cannot change the electrical service in your building. The kiln must be wired according to the building service.
When buying a used kiln, don't assume that just because the kiln worked in someone else's studio that it will work in yours. Check the serial plate on the kiln to see what voltage and phase it is wired for, and check what the service is in your studio. You can change the voltage of a kiln from 240 to 208 (or vice versa) by changing the elements. Switching from single to 3 phase (or vice versa) can be expensive and require a lot of rewiring in the kiln.
When in doubt, call your local kiln supplier or kiln maintenance expert. They will be happy to assist you. If you are going to buy a kiln from them, they may even be willing to come to your studio and do a site check and make sure the kiln you have selected is right for you.
If I can help you over the phone, please feel free to call me at (847) 223-1807. Happy kiln shopping!
