Researchers have identified a different kind of glass ceiling for women at work: AC. Air-conditioned offices are inadvertently designed to be physically uncomfortable for women. Maintaining an optimal office temperature is tricky as it relies on precise calculations of occupancy, clothing expectations, and system efficiency. But the basic processes used to figure out what makes a comfortable temperature may also be skewed, resulting in women feeling much colder than men, according to a 2015 report in Nature Climate Change.

Most building standards rely on a model of thermal comfort developed in the 1960s that uses clothing insulation and metabolic rates to calculate what temperatures will make people uncomfortable. The problem is, the metabolic rate system used is based on the resting metabolic rate of a single middle-aged man, even though metabolism changes with age, sex, and body size.

That rate may overestimate women’s intrinsic heat production by as much as 35 percent, according to the study by researchers at the Maastricht University Medical Center in the Netherlands. Women typically have lower resting metabolic rates than men, meaning that when women are sitting around an office, their body isn’t producing as much heat as a man’s body would. This affects not just women, but everyone in the office, since HVAC systems are calibrated to take into account the heat generated by people being in a room together giving off body heat (that’s why an empty conference room generally is much colder than a crowded one).

Reconfiguring thermal standards for offices to take into account the fact that the workforce is no longer largely male will not just lead to greater comfort for half the population, it’ll also lead to greater energy savings and more efficient buildings, reducing the amount of energy wasted when offices are refrigerated to Arctic conditions during the summer. We could finally start leaving our thick office sweaters home on sweltering days.