While my wife, my two kids and I were building our house, we had an out house out back that we used. It was simply a hole in the ground with a shack on top. No concrete, no fancy pressure treated wood. We used it for seven years and never once moved it. We used a bucket in the house first (this is Alaska) and dumped it every day. Our out house hole is about four feet deep or there abouts. We have permafrost here and that was as deep as the back hoe could get. Hard to believe that the ground can be so hard and frozen that the back hoe stands up when it has dug as far as it can. Our out house is still there to this day and it kept us going until we moved to town.
We did use lime to kill the smell. It changes the pH in there or something and sweetens the smell. You can buy septic tank aids that are used to help the bacteria grow (in the hole) and it helps things work faster. There is a product out there called septic tank aids. This is like a tablet that you can throw in the hole once in a while to help speed up the process of decomposition. We used one hole for eight years by using these tablets. Hardware stores and maybe stores like K Mart probably carry these. We got ours from our local Amway distributor. Adding a piece of plastic pipe about 4 or 6 inches in diameter on the inside from inside the seat part and up through the roof will also help ventilate off the methane gases helping with keeping the smell down.
Just make sure the shack is big enough to cover the hole. If the hole is a little big, run some planks across the hole to support the outhouse. We always seem to make the hole too wide and it can get very annoying with the smell and trying to make sure the house doesn't fall in the hole or that there is no open areas around the outside of the house. Our kids are big now, but we used to worry about them falling in. That would be a real stinky mess wouldn't it?
Offered by Clipper.