Co.Design

Why Your Office Is Freezing In The Summer

Bad building design makes for a chilly summer. Luckily, there are solutions that don't include buying a Snuggie.

It may be the middle of summer, but you'd never know from looking around offices, where, on the hottest days of the year, it's not uncommon to see workers wrapped up in sweaters at their desks. As temperatures outside rise, most corporate office buildings become hermetically sealed, air-conditioned ice cubes, forcing workers everywhere to grab a Snuggie. In a study of government office buildings, for instance, 60% of workers complained of thermal stress--that they’re too hot or too cold in their workplace. Why can’t we manage to keep offices at a comfortable temperature? 

Several things could be causing your building to turn into a frigid tundra every summer, ranging from not enough thermostats to an oversized cooling system to miscalculations about how many people will be in a room (and what they'll be wearing) at any given time. Luckily, there are solutions that don't involve buying a personal space heater.

Problem: Not Enough Thermostats

The more thermostats you have, the more you can control temperature variations throughout a building--someone sitting in direct sunlight has different air conditioning needs than a colleague sitting across the room on a shadier side of the building. But more control comes at a price. "Giving a thermostat to each office requires more wiring," says Georg Reichard, an associate professor of building construction at Virginia Tech. If you're looking to cut costs during the design phase of a new building, that's one of the first things to go. By skimping on the density of thermostats placed throughout the building, developers get a lower price tag, but occupants later pay the price in discomfort and inefficiency.

Problem: HVAC Systems Designed For The Wrong Era

The HVAC (heating, ventilation, and air conditioning) system may not be designed for the right conditions, either. Electronics are a major source of heat in offices, and air conditioning systems are designed to offset this. In newer office buildings, switching to LED lighting (or LED computer monitors) can lead to cooler temps, because LEDs don't get as hot as other types of lighting, like CFLs. But most buildings don't account for the difference in their estimations of how much a room should be cooled. HVAC systems designed for offices with older lighting technology--regardless of the facility's latest upgrade--are compensating for extra heat that isn't actually being generated, so they end up being much colder than intended.

Problem: An Unfortunate Seat In The Office

The speed of the fan pushing air into the room matters, too. "When the flow rate is increased, you perceive the air temperature as much lower," says Joon-Ho Choi, an assistant professor of building science at the University of Southern California. That's why even a bit of a breeze feels so refreshing. But if you're sitting by a vent that's constantly blowing air across your desk, you'll feel colder, even if the air isn't necessarily uncomfortably cold.

Usually, though, the air coming out of the vent is 10 to 15 degrees colder than the room's target temperature--since that flow of air warms up the farther it travels through the warm building. So someone sitting right next to an air conditioning vent might be shopping for a space heater while a few rows away, another employee is sweating.

Problem: Men In Suits Ruin It For The Rest Of Us

Of course, personal preferences play a role. Various studies indicate that women may be less tolerant of cold temperatures than men, for one thing. Dress codes make a difference, too. Men who wear full suits to work need the office to be a bit chillier to stay comfortable than women who wear sleeveless dresses. 

The industry mainstay as to what is a comfortable temperature may, in fact, be skewed toward the former demographic. ASHRAE Standard 55 is a widely used building code developed by the American Society of Heating, Refrigerating and Air-Conditioning Engineers to standardize temperatures of large buildings. Its mathematical model of comfort is calculated according to factors like air temperature, humidity, activity level, and clothing insulation. But often, building temperatures are set using men in suits as the standard occupants, leaving women--and anyone else who wears summer-appropriate attire--out in the cold.

Solution: Throw Open The Windows

Designers are figuring out ways to make buildings more comfortable in the summer, though. One method is simple: Let people open the windows. When you put people in an enclosed space with only artificial air, they tend to expect for it to feel perfectly comfortable. "When you introduce choice--allow for personalization and control--clients are willing to accept a greater range of temperatures," says Ryan Mullenix, a partner at global architecture firm NBBJ. The firm has used operable windows in several of its commercial projects, including in its Seattle headquarters. To discourage people from opening windows at inopportune times, like during a rainstorm, there's a light system installed in the wall. Based on humidity and air quality, the lights flash green to indicate it's a good time for fresh air, and yellow to indicate that the window should stay closed.

Solution: An App For Tapping Into Your HVAC System

For employees who don't have access to an open window, an app and software system called Comfy aims to make it easier to control the office climate. Once hooked up to a building's HVAC system, Comfy acts as kind of a personal thermostat, allowing people to request warmer or cooler air to their zone of the office via smartphone. A pilot program over several seasons at a corporate office in Milwaukee resulted in 23% less energy usage by the HVAC system, according to one of Comfy's designers.

The Hidden Costs

Freezing offices have costs beyond making employees uncomfortable. Blasting the A/C increases a building's operating expenses. The General Services Administration estimates that raising the temperature in federal buildings just two degrees in the summer would save the government $1.87 million per year. The cold also makes workers less productive. In 2004, a Cornell University study found that increasing office temperatures from 68 degrees Fahrenheit to 77 degrees Fahrenheit led workers to type more and make fewer errors in typing. The optimal temperature range for workplaces during the summer is between 74 and 76 degrees Fahrenheit, according to study author Alan Hedge.

So if you're feeling a little unproductive this summer, don't blame those summer Fridays. Blame your building's crappy HVAC system.

[Images: Icicles via Shutterstock]

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13 Comments

  • David Lees

    If you are sitting lower down than the thermostat it can be like sitting in the open top supermarket freezer. The cold air lying low may never get high enough up the wall to make the thermostat stop pumping out cold air. Especially bad if the AC grilles don't kick the air around enough to mix it and stop this stratification.

  • parker.joel

    I suspect that the most common problem here is upper management naively shutting off the heat thinking they are saving money. The truth is that the most efficient way to manage building temperature is to have one big chiller and reheat the air for each office. Modern buildings are designed this way. When well meaning but ignorant bosses turn off the heat, then all of the rooms are chilled based on the warmest room in the building. You should contact someone at Honeywell or Johnson Controls to explain this and maybe write a story about it so we can stop this wasteful and annoying practice.

  • Michael D. Miller

    Yes, being attentive to the proper use of the HVAC system is critical. Similarly, some drivers will not achieve high mileage from an energy efficient car.

  • dodo.brooke

    Shaunacy: A follow-up that explains that stuff to building managers would be great! I bet that ignorance (of good options) is an important factor in this; at least that could be addressed...

  • Having worked on building HVAC systems and the Chief Engineers who are in control of these systems really opened my eyes when I started out. It's not their fault, they have little control, the most they can do is adjust the one or two sensors in the room. Adding more sensors is only part of the problem, you would have to add more ducting and more VAV(Variable Air Volume) boxes and spread them around the room. It would be a nightmare to get working. Plus, in an office building, the temp in that one room will vary only a little throughout, unless there's sun coming through a window. Which, if the system was set up correctly, the temp sensor will never be in direct sunlight.The reason you feel cold is partly based on your attire. It's also based on how each person perceives temperature. It's not "freezing." the room is set at, lets say 73F. You're outside in 80-90F temps, coming inside and instantly dropping 7-17 degrees will make it seem "freezing" but it's actually not.

  • Michael D. Miller

    There is not much designers and facility managers can do about the attire of men and women who occupy office buildings. They need to work these problems out themselves. Also, the location of thermostats is equally important to the number for creature comfort.

    (Registered Architect / Florida)

  • pallsopp42

    Our work environments are generally poor places for human beings. Unfortunately, the bulk of our built environments have become real estate commodities to be built on the cheap and designed to generate huge financial returns for real estate investment trusts and other real estate financing organizations, including our resident geniuses on Wall Street and in our banking system.

    When design and systems for human comfort (as measured across many dimensions) are routinely subordinated to short term profit goals, we end up with the dreadful workplaces you describe.

    Thankfully far more attention is being placed on the very significant role that the places we inhabit play in chronic disease and being sick while at work. Operable windows are a fine idea - and of course nothing new. But designing and building on the cheap still, unfortunately, entails hermetically sealing buildings and keeping people breathing chilled air whose filtration systems leave much to be desired.

  • dodo.brooke

    While I appreciate your addressing a question I've long wondered -- and been very bothered -- about, I'm curious as to why you didn't address the amount of energy being wasted - and greenhouse gases being unnecessarily produced - by these absurdly low building temperatures - and modify your recommendations accordingly. For example: I'd think that opening the doors and windows would only increase the waste; if an HVACs output is linked what temperatures it "senses" in a space, opening doors/windows would only move the HVAC's to waste more energy replacing the cold air leaving the space via the open windows and/or doors. I wonder whether those calculations (re: amounts of energy wasted, GHG's unnecessarily produced, and linked HVAC recommendations) have been done...

  • Michael D. Miller

    You are correct. The notion of opening a window to warm a space which is being over-cooled is an absurd waste of energy. I am not not a big proponent of operable windows which only brings unfiltered air into the office space. Allergy sufferers hate this. I prefer HVAC systems which allow outside air to be filtered through the system. This provides "free cooling" when the outside temperature is below room temperature.