"Workers want more flexibility in their schedules, and with improvements in technology that enable employees to check in at any time, from anywhere, it makes sense to allow employees to work outside the traditional nine-to-five schedule," says Rosemary Haefner, chief human resources officer of CareerBuilder, in a release with the survey results.

"Moving away from a nine-to-five work week may not be possible for some companies (yet), but if done right, allowing employees more freedom and flexibility with their schedules can improve morale, boost productivity and increase retention rates."

Among the other findings of the survey:

• 20 percent said work is on their minds when they go to bed;

• 42 percent said they wake up with work on the brain;

• 20 percent said thinking about work interrupts their down time.

More men than women work outside the 9-to-5 time slot (44 percent vs. 32 percent), check email outside those hours (59 percent vs. 42 percent) and check on work communications during friend and family activities (30 percent vs. 18 percent). However, more women (23 percent) than men (16 percent) say work is the last thing they think about before going (or trying to go) to sleep.

The breakdown by age offered some insights, some perhaps unexpected. For instance, far fewer younger worker work outside of 9-to-5 than older workers, while the checking of work emails outside the office didn't vary nearly as much by age. Seven in 10 workers age 55 or older said they choose to connect to work outside the 9-to-5 hours, compared to 56 percent of 18-to 24-year-olds. Younger workers were far more likely than their older peers to go to bed and get up with work as the last and first thing on their minds.