It's no secret that California's regulatory and tax climate is driving business investment to other states. California's high cost of living also is driving people away. Since 2000 more than 1.6 million people have fled, and my own research as well as that of others points to high housing prices as the principal factor.

The exodus is likely to accelerate. California has declared war on the most popular housing choice, the single family, detached home—all in the name of saving the planet.

Metropolitan...