The History of Air Conditioning in Seattle
Early Climate Comfort in a Mild Climate
Seattle, nestled in the Pacific Northwest, has historically enjoyed a temperate marine climate, with cool summers and mild, wet winters. For much of the 20th century, this relatively moderate weather meant that air conditioning (AC) was considered a luxury rather than a necessity. Natural ventilation, shade from Seattle’s abundant trees, and cooler summer nights typically sufficed for most residents and businesses.
For decades, the need for mechanical cooling was low. In fact, up until the early 2000s, only a small percentage of homes and even fewer apartment buildings in Seattle had central air conditioning or window units. Commercial buildings were more likely to be equipped with AC, particularly in downtown offices and retail spaces, but it was still not as widespread as in other U.S. cities.
According to census data and surveys conducted by the Puget Sound Regional Council and others, even by 2013, fewer than one-third of Seattle homes had any form of air conditioning.
Rising Temperatures and Growing Demand
The shift began in earnest in the 2010s as Seattle started to experience more frequent and intense heatwaves. Climate change has played a key role in reshaping local weather patterns, with longer, hotter, and drier summers becoming more common. Events like the historic June 2021 heat dome, which saw temperatures spike to 108°F (42°C) in Seattle—far above historic norms—dramatically highlighted the city’s vulnerability to extreme heat.
These extreme weather events caused a surge in public awareness and demand for cooling systems. HVAC companies in Seattle reported record installations and backlogs after such heatwaves. Portable units and window ACs flew off store shelves. Simultaneously, landlords, policymakers, and developers began re-evaluating building standards and residential requirements around cooling.
In recent years, new apartment buildings and commercial spaces in Seattle are increasingly built with central or ductless mini-split AC systems. Some local building codes have started to consider cooling needs, particularly for vulnerable populations such as seniors and low-income residents.
Seattle’s public schools, many of which lacked AC for decades, have also begun implementing cooling retrofits. Similarly, community centers and libraries with AC have been used as designated cooling shelters during extreme heat events.
Seattleites look to beat the heat in other ways
Looking Forward
Seattle's historical lack of AC is now being reconsidered in the context of a warming climate. While the city still has a lower rate of residential AC ownership than much of the country, the trend is quickly shifting. Climate adaptation efforts are focusing on sustainable cooling methods, including passive design, green roofs, and high-efficiency heat pumps, which provide both heating and cooling.
As hotter summer temperatures become the new normal, Seattle residents continue to seek out effective ways to beat the heat. Air conditioning and HVAC companies have continued to see a rise in demand, especially in older buildings and homes. Libraries and community centers have invested in installing AC to meet the needs of the community and public campaigns about heat exhaustion and heat stroke have become commonplace during the summer months. While these retrofits and solutions provide necessary relief to the city’s residents, Seattle is still playing catch up with the changing climate.