Composting Toilets


Goal is to transform waste material back into nutrients through decomposition and evaporation.  Composting toilets achieve this either internally or externally.

  • Internal units attempt to accelerate the decomposition process by mixing carbon additives to aerate waste and heat to accelerate evaporation. Under the right conditions, the ‘finished’ compost may be free of pathogens and suitable for use as fertilizer.
  • External units simply collect waste in compostable bags which are removed and added to an external compost bin/pile to complete the decomposition process.


Systems are either self contained or plumbed to a remote composting tank.

  • Self contained units require more internal floor space than a traditional toilet, a through-wall/ceiling vent and in some cases a power supply to operate heating unit and/or exhaust fan.
  • Remote systems use a marine/RV style toilet plumbed to a remote tank located under or behind the restroom. They also require exhaust vents and power and in some instances water.  These systems have a much larger capacity, which means they require less frequent compost removal.


Sun-Mar - Self contained and remote systems with internal composting.  The only self-composting toilet to be listed with the National Sanitation Foundation (NSF) and American National Standards Institute (ANSI) standard 41-1999. 




Envirolet – Self contained and remote systems with internal composting



Natures Head - Self contained system with internal composting




Separett – Self contained system with external composting