Imagine a building made of sky.

For the first time in history, we can build pretty much anyting out of carbon that we coaxed from the air. We can structure any architectural style with wood, we can insulate with straw and mushrooms, we can make concrete - better concrete - with clay, microbes, smoke, and a careful look in the rear view mirror and the microscope.

All of these emerging technologies - and more - arrive in tandem with the growing understanding that the so-called embodied carbon of building marerials matters a great deal more than anyone thought in the fight to halt and reverse climate change.

The built environment can switch from being a problem to a solution - much nicer places to occupy that just happen to pull carbon out of the air.