The composting toilet and its use

What is a composting toilet?

A Composting toilet is a dry toilet where the feces enter directly into a container filled with absorbent substrate and are composted there. After composting, the excretions can be used biologically as fertilizer or disposed of micro-biologically harmlessly.

Conventional composting toilets do not separate the urine, but it is collected together with the feces in a bucket. Depending on the design and location, a distinction is made between variants with collection containers, composter or combination tanks.

How do composting toilets work?

In contrast to the chemical toilet, in which one only combats the rot and thus the odor by ecologically dangerous substances, the feces are disposed of in an environmentally friendly manner in the compost or dry-toilet.

The functioning of the composting toilet is simple. The excretions are collected in different containers, the organic degradation processes run their course and the feces can be further processed into humus with the emptying of the collection container on the compost heap. Through composting, the composting toilet contributes to the natural cycle of the biological process. Since water flushing is not required, the dry toilet saves the precious raw material water, which is an additional advantage.

The composting toilet should have an exhaust air system, as unpleasant odors are created by the mixing of urine and feces. Alternatively, the rotting processes can also be counteracted by covering the excretions with odor-binding and absorbent materials after each toilet use. The disadvantage here is the frequently required emptying of the container and the fact that the compost may become too wet despite the water-binding substances.

Separating toilet – where the urine is collected separately from the solids – can be composting toilets as well. The clear advantage of this type is that the solid excretions dry out quite quickly and the composting toilet is practically odorless. Such models then have an appropriate ventilation system, which fastens dehydration.

How does it become soil?

The dried solid excretions and possibly toilet paper residues can be safely applied on a compost heap.

There, together with the other plant materials, they go through the classical rotting processes over several months and eventually become humus. The microorganisms and possibly pathogens from the excrements are degraded or killed over time.

Compost with excretions from the composting toilet should mature for at least 1 year.

Alternatives are fast or thermo-composteres,in which temperatures of about 60-70 degrees are reached inside the compost, thus greatly fastening the rotting and degradation of pathogenic substances and weed seeds.

Pros and cons of composting toilets


  • Conserving water resources
  • No smell (with venting system)
  • No polluting chemicals
  • Compost is a valuable fertilizer


  • Possibly unpleasant smell
  • Power for vent
  • Frequent emptying (for small containers)