Dry toilets do not use water and can be useful where water supply is extremely limited. There are two types of dry toilets: pit toilets with waste going directly into a hole in the ground or pit, and composting toilets where waste goes into a sealed container or cavity installed above the ground or in the ground. A dry toilet can be a useful addition to a flush toilet for crowded households. Dry toilets do not usually dispose of grey water.

The advantage of a pit toilet is that it is cheap to construct, requires little maintenance and has no moving parts. Disadvantages include the need to dig a large hole and to relocate the toilet when the pit is full. In high rainfall areas with a high water table, the pit will need to be lined to avoid collapse, can fill up with water, may smell and may pollute the water supply.

Composting toilets cost more to build and require regular maintenance. However, a composting toilet that is well constructed and sized to match the house population will not produce much odour and can be used for many years. Since composting toilets are located above a compost container, this often requires stairs and can make access difficult for people with limited mobility.

As with any other toilet, dry toilets need toilet roll holders, privacy locks, light, good ventilation, and a high shelf for toilet roll storage. A hand washing point should be provided near the dry toilet to prevent the spread of disease. Survey data show that 5% of surveyed houses had a dry toilet (combination of an in-ground pit toilet and contained composting toilet).

Ensure

• B3.5.1.

  PIT TOILET- it is located away from water courses and bores, check local building regulations for recommended distances from a water source, but as a guide a minimum of 100m is recommended

• B3.5.2.

  PIT TOILET- the bottom of the pit is above the highest water table level

• B3.5.3.

  PIT TOILET- the pit is fully lined if it is close to a bore or water course or if there is a high water table

• B3.5.4.

  PIT TOILET- the pit is well vented, drawing air into the pit through the toilet bowl and exhausting air via a dark coloured pipe exposed to the sun that will act as a thermal chimney extending above the roof line, to ensure smells are taken away.

• B3.5.5.

  COMPOSTING TOILET - the residents are comfortable with the idea of emptying the chamber and disposing of the compost material, and that this does not conflict with any cultural beliefs

• B3.5.6.

  COMPOSTING TOILET - the type and size of toilet is suited to the household population and expected fluctuations in usage

• B3.5.7.

  COMPOSTING TOILET - the residents have the resources and skills to undertake necessary maintenance

• B3.5.8.

  COMPOSTING TOILET - if the toilet requires a fan, electricity is available

• B3.5.9.

  COMPOSTING TOILET - there is enough space under the building to install, access and maintain the compost chamber.

• B3.5.10.

  Any DRY TOILET system - it is conveniently located for use by residents

• B3.5.11.

  Any DRY TOILET system - it is down wind of living areas

• B3.5.12.

  Any DRY TOILET system - it has natural and electric lighting

• B3.5.13.

  Any DRY TOILET system - there is adequate natural ventilation

• B3.5.14.

  Any DRY TOILET system - a locking door, toilet roll holder and shelf are provided in the cubicle

• B3.5.15.

  Any DRY TOILET system - hand washing facilities are provided near the toilet

• B3.5.16.

  Any DRY TOILET system - the pit or chamber and vent are protected by fly screens.

Consider

• building a path between the house and the toilet, which is slip resistant and accessible to people with disabilities
• using a self-closing toilet lid, to provide more protection against flies
• designing the cubicle to comply with AS 1428.1 Design for access and mobility, and locating the hand washing point that can be accessed by people with disabilities
• providing the capacity to install grab rails in the future.

• the composting toilet and cubicle are built as specified
  

  When: COMPLETED DESIGN & SPECIFICATION
  DURING CONSTRUCTION
  AT HANDOVER
  FINAL COMPLETION
  TRADE TEST

• the composting toilet has been installed to the manufacturer's requirements and a certificate has been provided
  

  When: COMPLETED DESIGN & SPECIFICATION
  AT HANDOVER
  FINAL COMPLETION
  TRADE TEST

• there is access to the composting chamber for maintenance
  

  When: SKETCH DESIGN
  COMPLETED DESIGN & SPECIFICATION
  DURING CONSTRUCTION
  AT HANDOVER
  FINAL COMPLETION
  TRADE TEST

• it is not possible for stormwater to enter the composting toilet pit or container
  

  When: SKETCH DESIGN
  DURING CONSTRUCTION
  AT HANDOVER
  FINAL COMPLETION
  TRADE TEST

• the composting toilet pan and lid are stable and secure
  

  When: AT HANDOVER
  FINAL COMPLETION
  TRADE TEST

• the composting toilet roll holder and shelf are securely attached to the wall
  

  When: AT HANDOVER
  FINAL COMPLETION

• there is a hand washing point nearby the composting toilet
  

  When: SKETCH DESIGN
  COMPLETED DESIGN & SPECIFICATION
  DURING CONSTRUCTION
  AT HANDOVER
  FINAL COMPLETION
  TRADE TEST

• the composting toilet installations are accessible for people with disabilities.
  

  When: SKETCH DESIGN
  COMPLETED DESIGN & SPECIFICATION
  AT HANDOVER
  FINAL COMPLETION

AS/NZS 1546.2:2008 On-site domestic wastewater treatment units - Waterless composting toilets

Your Home - Waterless toilets, 2021 - https://www.yourhome.gov.au/water/waterless-toilets

NSW Health -
WATERLESS COMPOSTING TOILETS (WCT) ACCREDITATION GUIDELINE, 2010 - https://www.health.nsw.gov.au/environment/domesticwastewater/documents/wct-accred-guideline.pdf

Martin, M. 2004, Waterless Composting Toilets, Bush Tech #23, Centre for Appropriate Technology, Alice Springs

Martin, M. 2003. Pit Toilets, Bush-Tech 15, Our Place Magazine. Centre for Appropriate Technology, Alice Springs

Martin, M. 2002. Choosing the right toilet, Bush-Tech 15, Our Place Magazine. Centre for Appropriate Technology, Alice Springs

Khalife, MA, Dharmappa, HB & Sivakumara, M 1998, “An Evaluation of Septic Tank Performance in a Remote Australian Village Provides Insight for Optimizing Onsite Treatment Systems”, Journal of Water Environment Research, Edition 4, Volume 10, USA, Water Environment Federation, pp 33-36