Green roofs and solar chimneys are here – experts say it’s time to use them

Builders already have the tools needed to build cooler homes for an increasingly hotter world

The US sweltered under record-breaking heat this year, with new research suggesting that air conditioning is no longer enough to keep homes cool. Spiraling energy demands and costs of indoor cooling now have planners looking to alternative ways to keep buildings cool - some fresh out of the lab, others centuries old.

The amount of buildings we expect to go up in the next couple decades is just staggering," says Alexi Miller, director of building innovation at the non-profit New Buildings Institute (NBI). If we build them the way we built them yesterday, we're going to use a phenomenal amount of energy. There are lots of ways we could be doing this better. It's not all fancy, emerging technology - there's some basic stuff we don't do nearly enough."