The phrase “Thank God it’s Friday” may soon become moot if employees continue to extend their work weeks. In a Steelcase Inc. study of 141 people, 60% said that at least once a month they devote a portion of the weekend to work. Of those, 42% spent between six to 10 hours working either at home or the office; 8% clocked 11-15 hours; 10% spent 16-20 hours and 5% put in 21 hours or more. The survey also revealed that more than half the respondents work more than 40 hours Monday through Friday. One-third admit to taking work home at least one night a week. An unspoken rule was the most cited reason for the overtime.