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?

Automatic smart leak-detection shut-off valve

Needs the grid

One of 2 ways to meet this need. Cost, carbon, footprint and rankings are relative to other solutions for the same need, not absolute.

A motorised valve on the main water pipe with a sensor that learns the household’s normal use. When it detects water running when it should not, from a burst pipe or a steady drip, it shuts the supply off by itself. It stops leaks you would not notice, but depends on power and cannot be repaired at home.

Cost

Medium

Upkeep

Occasional

Skill to build

Specialist

Lifespan

10-15 years for the motorized valve and electronics, a sealed, non-field-repairable unit per its own description

Embodied carbon

Low

Space / material use

Low

Output timing

Continuous process

Skill to repair

Specialist

Inputs

• Potable water
• AC electricity

Outputs

none

Compare the 2 ways to meet this need

Levels are relative to the other options for this need, not absolute. Fewer dots is lighter.

• Automatic smart leak-detection shut-off valve (This page)
  Can I use it? Works in a flat · No rebuilding needed
  What does it cost me? Upfront cost: Medium · Skill to build: Specialist · Upkeep: Light · Change to daily life: None · Works without the grid: No
  Choose it if you want leaks you would never notice stopped automatically.
• Manual isolation valves at key points
  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 to isolate one section for a leak or a repair, cheaply and by hand.

Sources

• Smart leak-detection valve industry sites (StreamLabs, Phyn, FloLogic, Moen Flo)

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.