From the July 2005 issue of Entrepreneur

Sure, your employees might stare longingly out the window, gazing at a summer sky and wishing they were off sunbathing. But chances are, it's the weather inside the office that's causing your staff more concern. You should be concerned, too, if your assistant is constantly fanning herself or your CFO is dressed in a parka--in the middle of June. A recent study conducted by Alan Hedge, professor of design and environmental analysis at Cornell University, indicates that the temperature of your office is directly related to how your staff is performing.

The study sampled the air every 15 minutes at nine workstations in an office. It also monitored the time the workers used their keyboards and the time they spent correcting their errors. At 68 degrees Fahrenheit, workers typed 54 percent of the time, with a 25 percent error rate; at 77 degrees, the staff typed 100 percent of the time, with a 10 percent error rate. Some companies are starting to acknowledge the problem by installing "personal environment modules," desktop units employees use to control individual settings for air temperature, air flow, radiant heat and lighting.

This doesn't surprise Jonathan Harber, 41, CEO of SchoolNet, which helps educators identify student weaknesses and develop plans to improve performance. Comfortable temperatures are rarely felt by the staff of about 40. SchoolNet's headquarters in New York City's Chelsea Market is a former Nabisco factory--and a notoriously drafty building

During the winter, the building's interior is approximately 80 degrees, while the outer offices hardly crack the high 50s. In the summertime, everything reverses: The outer offices are cooked, but the inner offices are refrigerated. "It gets annoying, especially when you're in a conference room in the middle of the building, it's getting hot, and people start nodding off," says Harber. "And then people come in from other parts of the building, complaining that it's too cold." Harber stocks his own office with a heavy sweater and gloves with finger holes so he can type.

As they're outgrowing the premises, Harber has been looking for new offices that will provide a more temperate working environment. "Before you lease [space], ask if they use an air-coolant or water-coolant system," advises Harber, who says water-cooled air is generally more expensive. "And find out if they charge you based on the time you use the air conditioning. If they shut off the air after 5 p.m., and if you or your employees are working late and turn it on, that can run $500 to $600 an hour. It's disconcerting to spend all your time managing the business, then find out your air conditioning can make a bigger difference to your bottom line than some of your products."