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?
Electrochromic (smart) glazing
Needs the grid
One of 6 ways to meet this need. Cost, carbon, footprint and rankings are relative to other solutions for the same need, not absolute.
Glass that darkens or clears at the touch of a switch, through a thin electrical coating between the panes. It can block the summer sun and let the winter sun in, instead of being a fixed compromise. It cuts cooling costs, but costs two to three times more than ordinary glazing and a fault means replacing the whole window.
Build it
This solution is not buildable as a DIY project.
Cost
High
Upkeep
None
Skill to build
Specialist
Lifespan
20-30 years commonly quoted payback/service horizon; the coating/control system is proprietary and unrepairable outside a factory per its own description
Levels are relative to the other options for this need, not absolute. Fewer dots is lighter.
Electrochromic (smart) glazing (This page) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: High · Skill to build: Specialist · Upkeep: None · Change to daily life: None · Works without the grid: No Choose it if you want each window to let the sun in or keep it out at the touch of a switch.
Triple-glazed, low-E windows Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: High · Skill to build: Intermediate · Upkeep: None · Change to daily life: None · Works without the grid: Yes Choose it if you want the windows that keep the most heat in.
Double-glazed windows, insulated frames Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Medium · Skill to build: Intermediate · Upkeep: None · Change to daily life: None · Works without the grid: Yes Choose it if you want most of the gain of new windows for a lower price and weight.
Secondary glazing (retrofit inner pane) 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: Daily · Works without the grid: Yes Choose it if you rent, or must keep your old windows, and want a cheap extra layer.
Insulated operable shutters Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Low · Skill to build: Basic · Upkeep: Regular · Change to daily life: Daily · Works without the grid: Yes Choose it if you want the strongest night-time insulation over the glass for little money.
Insulated draft-blocking curtains 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 stop draughts at the window with something you can sew yourself.
Sources
HomeAdvisor / SageGlass / architect trade press
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.