Britain's housing stock was built for a cooler, wetter climate — and that mismatch is becoming an expensive liability. A new wave of alternative home designs, from earth-sheltered dwellings to homes with deep eaves, cross-ventilation shafts and reflective render, is being road-tested as the UK grapples with a future of more frequent 40°C summers. The BBC's exploration of these prototypes is not a lifestyle curiosity; it is an early signal of a structural shift that property investors, developers and landlords need to start pricing into their decisions today.