A dry compost toilet is a facility where human excrements can be disposed. Instead of getting flushed away with large amounts of drinking water, the remains stay in place and have to instantly be covered with a thin layer of fly ash, sand or sandy earth. This prevents any smell and dries up the liquids. Paper and other biodegradable stuff can be added, but of course no tampons or sanitary pads consisting of, or including, artificial fibers.
The facility consists of at least two chambers. When one of them is full, you close it for a while and use another one. The faeces are left to rot and can later be taken as compost in the garden or a field. The decomposting takes between six and twelve months, depending on the climate.
The dry compost toilet is a one-and-a-half story building which consists of a bathroom on top of two chambers, at least aboout 1.5 m³ each. The facility can be constructed in bricks, stone or concrete. On top of each chamber you leave a hole of one foot by almost one foot for defaecation. For the sake of hygiene and in order to keep things simple, you may not want to install a "throne", but just squat over the top hole. Many people install one nevertheless.
Leave another hole to one side of the wall of each chamber, at the bottom of the building. It has to be just large enough for shoveling out the compost. You keep it closed with a strong grid door which lets insects and worms pass. So the door has to open towards a garden or forest. Do not seal the door hermetically, and do not seal the ground nearby it.
The orthodox building is identical to the simple construction except for additional inventory: To keep the faecal remains completely dry, urine has to get collected separately. You have to install a flat basin right in front of the top hole of each chamber. A pipe drains the urine into a reservoir, along with a little bit of flushing water which you might want to use to keep basin and pipe halfway clean. Mix the reservoir liquid with waste water from the household and use it for spilling your garden plants.
- Sustainable sanitation, a large gallery of photos taken all over the world