I’ve been wondering ever since the Hypercolor days why no one sells a house paint that changes from black to white as it gets warm. The same goes for shingles, jackets, etc. I can only assume that the costs of production must still outweigh their value as an active thermal insulation, but now that I see this, I’m tempted to at least make myself a jacket. In the video below, there is a tutorial on how to make fabric that quickly changes from black to white as it gets hot.