In the summer of 2007, halfway through my MFA degree I took on the task of designing and building a woodfire kiln in my backyard next to my studio. With the help of books by Mr. Fred Olson and some others I began designing my kiln. I wanted it to be small enough that I could fire it myself but big enough to make firing it worth while. I looked at Brick costs and castable prices and with some information gleamed from a few other potter friends I set out to build a home-made castable wood fire kiln. I got the brick for thr floor for an abandon brick factory some friends had told me about. they are mis macthed and some are cracked but for the most part in real good shape.
My finally decision on cast formula ended up 1 part Portland Cement, 2 part Fireclay, 2 part Grog ( which was made up of a medium course and self crushed bisque), 3 Part Mill sawdust. I mixed it in on old cement mixer of my father's and shoveled it into the cast when it was just a little wetter than cookie dough. I casted 2 walls and then filled in and mounded and cast the ceiling. All where between 4 1/2 to 6+ inches thick.
I had read that even sized kilns fired much better so I sized mine roughly 2ft high by 2ft wide, this also allowed me to used standard size shelving (hurray!!!). I carried this dimension for 5 feet. It had also come to my knowledge that in kilns such as this there tends to be cool spots when you get outside of the main draft corridor, especially in the back. To fix this I decided to taper the back of the kiln from its 2ft by 2ft diameter down to a 1ft by 1ft diameter. So after the 5 foot section I have a 2 foot section going from 4sqft to 1 sqft. I found this taper did 2 things first it did cut out the cool spots, but italso dramatically increase the draft, though a breif look at fluid mechanics would have told me that beforehand.
The flue I went ahead and spluged on. At first I wanted to cast it as well but after dealing with the mix the first time I decided that just buying the bricks and stacking thing would be enough work for me. The bricks climb about 5 1/2 ft. and then I have a section of ventalation tubing for the next 5 ft.
All told it took me about 3 weeks and roughly $800 to build my 20cubic ft wood fire kiln. And to be honest I feel pretty good about that. Here are some photos, enjoy and if you have any questions please ask me, thanks.

First I layed out the basic area for the Kiln


Then using the brick I had scavenged I set the floor.


I then set the form and poured (shoveled) my castable


And Its a bueatiful Baby Woody
( PS Thats my portly self in the back)