The Dogtrot House and the boom of the south thanks to air conditioning

Dog Trot House
Before A/C there was the Dogtrot House — two houses under one roof – one half for cooking and the other half for living, with a a breezeway down the middle to keep occupants cool in hot southern climates. These types of houses were common in southern states in the pre-air-conditioning era.

The Sunbelt, the area spanning from the southwest to the southeastern U.S., experienced above-average growth from 1950-2000 with the explosive growth of air conditioning. From Nevada to Florida, electric utilities experienced the same explosive growth as their systems had to expand to accommodate the new power demand.

Many other tricks were used to keep houses cool, such as transoms (a small window above a door which allowed warmer air at the ceiling to circulate up to higher floors, providing more air flow throughout the house), tall ceilings with fans that operated via electricity or rope systems, porches (screened and sleeping porches were common), reflective roofs made of lead, tin or copper that reflected the intense summer sun’s heat away.

As air conditioning became more common and cost-effective, home designs evolved to what we’re more familiar with today.

Sources:

Keepin’ It Cool: How the Air Conditioner Made Modern America

How Homes Kept Cool Before the Age of A/C