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?
Desiccant moisture absorber
Passive
One of 2 ways to meet this need. Cost, carbon, footprint and rankings are relative to other solutions for the same need, not absolute.
What your site needs
None.
A container of salt crystals that draw water vapour out of the air in a small damp space, a cupboard or a wardrobe, and drip it into a tray below. It treats a pocket of damp; it does not dry a house. Ventilation, airing and drying laundry outdoors come first.
Levels are relative to the other options for this need, not absolute. Fewer dots is lighter.
Desiccant moisture absorber (This page) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Low · Skill to build: None · Upkeep: Light · Change to daily life: Occasional · Works without the grid: Yes Choose it if a cupboard or a small room stays damp and you want to draw the moisture out with no power.
Hygroscopic natural finishes (clay plaster, exposed wood) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Low · Skill to build: Intermediate · Upkeep: Light · Change to daily life: None · Works without the grid: Yes Choose it if you are finishing walls anyway and want them to even out humidity on their own.
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.