How Houses Were kept cool before the age of AC

Earlier this summer, my next door was complaining to me about how costly his electric bill had gotten due to running his air conditioning system. I was shocked when we compared inside temperatures and bill amounts and realized that despite the fact that his house is a single-level home and about 70 years newer than my 1920’s split-level, his electric expense is considerably higher. “How can that be?” he asked “That drafty old house should cost you an arm and a leg!” I replied “I guess they just don’t make them like they used to!” Not until the last few weeks did I realize just how right I was. That conversation got me thinking about all the things about older homes that are basically designed to conserve energy.
It makes sense, really. Air conditioning systems didn’t become a common feature in American homes until after World War II, and homes built before then had to have architectural and strategic features to help them and their residents stay cool in the summer. Here is a breakdown of some of those features, as well as a few extra tricks used by our grandparents’ generation to avoid melting during the sweltering heat of summer back in the “old days” before we became reliant on air conditioning.

Interior Controls:

Wall Thickness
One of the biggest things about older homes that helped them conserve energy was the thickness of the walls. The exterior walls of many quality older homes were made of brick or stone, which provided a great deal of insulation and protection from the outside weather. In fact, in southern states where the weather got especially hot in the summer, brick and stone walls were commonly made 12-24 inches thick, a huge difference from the 2×4 or 2×6 lumber used in most modern construction.
While the thick stone walls kept heat from penetrating the house during the day, they did absorb heat, which could more easily be eliminated from the homes later in the day when cooler night air prevailed. Which brings me to my second point:

Airflow, Airflow, Airflow!
 The split-level designs of many older homes featured open stairwells that freely and naturally allowed warm air to rise to the upper levels. In fact, some older homes even had turrets or towers that sat above the living spaces of the home to collect heat and allow it to be vented from the home. Even without turrets, however, strategic opening of windows in the home maximized the flow of cool air through the home. For example, if the wind was from the west, basement or first-floor windows would be opened on that side of the house, and on the opposite side of the house, windows on the second floor would be opened to essentially draw cool air through the house and eliminate heat with the natural force of the outside breeze. Fans could also be used to increase this effect.

In southern states, where basements are not as common, many homes would actually be built on top of blocks that allowed breeze to flow underneath the living space of the house all the time.
Higher Ceilings & Larger Windows

Another way that older homes facilitated air movement and removing heat from living space was through higher ceilings. Most modern homes are built with 8 foot ceilings being the standard, but in the pre-air era, ceilings of 10-14 feet were very common. Naturally, heat tended to rise to the ceiling while lower areas stayed cooler. Ceiling fans also encouraged this effect, commonly used to draw heat upward in summer months and to blow it downward in cooler months.
Another way that warm air could be eliminated from rooms in older homes was through transoms, which were essentially small windows over doorways. Transoms were very common in older homes, both over interior and exterior doors to vent heat from the highest points of the room. Over exterior doors, hinges and special hardware allowed the transoms to be easily opened to allow airflow but still provided a degree of security to the home.
Transoms weren’t the only way windows were used differently in the old days, of course. Many older and historic homes had extra-large, double-hung windows. During the day, the top window could be opened to allow heat to escape near the ceiling, and at night, the bottom window would be opened to let cooler air inside. Not only did windows tend to be larger in the days before air-conditioning, there also tended to be more of them. To control the heat of direct sunlight pouring through these windows, large, heavy drapes were often used. Though there were other ways to control the effects of the sun, which brings me to my next point:
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