As potable water becomes more scarce all over the world, individuals and governments are re-examining the practicality of the composting toilet. A properly maintained composting toilet is odor-free and as easy to use as a flush toilet. It also provides valuable compost for gardens and saves thousands of gallons of water a year.
Begin by creating a compost heap. The contents of your toilet will periodically be emptied onto the heap along with food scraps, garden clippings and other waste. You need a bin to which you can add waste, one that holds aging compost and a bin for sawdust, peat moss or other organic material to be mixed in with the waste to create the compost.
Choose the container for the waste that will be collected by your toilet. Options include 55-gallon steel drums and plastic storage bins, but most people opt for a sturdy 5-gallon bucket, which can be easily carried to the compost heap.
Design and build a cabinet or bench to match your bathroom decor. Some composting toilets consist of a simple wooden cabinet, while others are elaborate, perhaps covered in decorative tile and including extras such as magazine racks. Remember to include a place to store the organic material you will be adding to the waste container to cover your waste and begin the process of composting. You also need a way to access and remove the waste container.
Install a seat and lid from a flush toilet on the top of the cabinet. Make sure it fits snugly over the waste container. A gap between the container and the seat can lead to waste missing the container.
Vent the cabinet with a vertical pipe that leads to the exterior of your home so there will be adequate airflow to allow for evaporation of moisture and eliminate odors. You can connect the vent to a wind turbine to increase airflow or include an electric fan.
Consider beginning the composting process inside the toilet. You will need to add microbes to the waste container in addition to the cover material and the toilet may need the addition of a heater if it is in an unheated area so the microbes won't die. You will also need a method to periodically stir the contents of the waste container so the microbes at the bottom get enough air.
Consider a two-container system. When the first container is filled, replace it with an empty container so the toilet can be used while the container is being emptied. Or use three containers, setting one aside until the second is filled and take both to the compost heap at the same time. If you don't want to build a composting toilet, you can purchase one. Some commercial models route the waste to a bin outside the home or in the basement, eliminating the need to maintain a compost heap.
Learn how to properly maintain a composting toilet and compost heap. Problems can result in foul odors or the spread of disease. Don't use your compost to fertilize vegetable or fruit plants in which the vegetable or fruit comes in direct contact with the soil, such as carrots or strawberries.