Lowtech Graph lists low-tech options for every need of a home. Here you can compare them, find tutorials to build them, and link them together into a circular system. Why low-tech?
Low-flush toilet
Passive
One of 5 ways to meet this need. Cost, carbon, footprint and rankings are relative to other solutions for the same need, not absolute.
An ordinary flushing toilet designed to use much less water per flush than a standard cistern. It works like any toilet, so nothing changes for the household. It cuts the water bill, but still sends sewage on to be treated, and can be fed from rain or reused water instead of drinking water.
Build it
This solution is not buildable as a DIY project.
Cost
Low
Upkeep
Occasional
Skill to build
Basic
Lifespan
Fixture itself: 25-50 years (vitreous china rarely wears out; flush valve/fill mechanism needs replacement every 5-10 years)
Embodied carbon
Low
Space / material use
Low
Output timing
Continuous process
Skill to repair
Basic
Regulation (FR example)
On-site sanitation (assainissement non collectif): the installation must be declared to and approved by the local SPANC before work starts, and is subject to periodic inspection. Arrete du 7 septembre 2009 modifie.
Levels are relative to the other options for this need, not absolute. Fewer dots is lighter.
Low-flush toilet (This page) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Low · Skill to build: Basic · Upkeep: Light · Change to daily life: None · Works without the grid: Yes Choose it if you want nothing to change in use, with less water per flush.
Composting toilet (dry) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Medium · Skill to build: Basic · Upkeep: Regular · Change to daily life: Way of living · Works without the grid: Yes Choose it if you want to use no water at all and make compost from the waste.
Urine-diverting dry toilet (UDDT) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Medium · Skill to build: Basic · Upkeep: Regular · Change to daily life: Way of living · Works without the grid: Yes Choose it if you want a dry toilet with fewer smells, and urine as a quick garden fertiliser.
Flush toilet (standard cistern) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Low · Skill to build: Basic · Upkeep: Light · Change to daily life: None · Works without the grid: Yes Choose it if you want the standard toilet every plumber knows, on mains water and sewer.
Living toilet (urine-diverting, larvae-processed) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Low · Skill to build: Basic · Upkeep: Heavy · Change to daily life: Way of living · Works without the grid: Yes Choose it if you live in a flat with nowhere to compost and want waste turned odourless in days.
Sources
General toilet-fixture industry durability consensus
Limitations of this page
We don’t list sizing or quantities, as the yield of each technique depends on the quality of its build. The catalogue compares options but doesn’t dimension them. Regulatory notes are indicative, with a French example, and need to be confirmed locally.