According to a recent Gallup survey, full-time employed Americans work an average of 47 hours a week. That's nearly a full day longer than what was once the standard schedule, the classic five-day, 40-hour workweek.

However, a Troy, Michigan-based mortgage company has come up with a novel idea: a strict 8-hours-a-day, Monday-through-Friday work schedule for the company's 1,350 "team members" — the term the top executive uses to describe employees.

"Your work every day is part of your life; it's not your life," Mat Ishbia, president and CEO of United Shore Financial Services, said to CNBC's "On the Money" in an interview.

"We want them to work hard for 40 hours," Ishbia said. "And then, go be with your families, go spend time outside of work, refresh, recharge and get ready for the next week."

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United Shore has some flexibility when employees start their workday, but not in when they finish. The standard is eight hours of work with an hour off for lunch.

Ishbia said that since they work with mortgage clients throughout the country, "We have different times based on our clients, 9-to-6, or 10-to-7 or 8-to-5, but we're pretty flexible with whatever works best for their family."

Still, surveys show many workers don't leave their jobs behind after they leave the office. One in four workers say they check on email during activities with family and friends, according to CareerBuilder study.

Founded in 1986, United Shore is the country's second-largest independent mortgage lender, and is on track for $13 billion dollars in loans this year.

Ishbia said the concept of the "firm 40" grew out of the supply and demand nature of the mortgage business, "which is so interest rate sensitive."

The company, he explained, was "finding people were burning out, or working really slow." Ishbia said their solution was "we came up with a way to overstaff, to handle high-volume times, and not have to work 60 or 70 hours a week."

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Gallup found that, on average, 21 percent of U.S. full time workers clock in between 50 and 60 hours. And 18 percent say they work 60 hours a week or more.

"There's a lot of evidence, particularly when people get to the point of being exhausted, that their performance and their basic cognitive ability falls a lot," Peter Cappelli, management professor at the University of Pennsylvania's Wharton School, told CNBC.

"There's pretty good evidence that you can wear people out and you can wear them out pretty quickly, in terms of overwork," Cappelli added.

Ishbia says the 40-hour policy is paying off, but "it's not saving us money because of less overtime, it's saving us money because … we have less turnover, happier teammates [and] they all work harder."

Wharton's Cappelli says there are numerous organizations where people feel they have to show up and put in time — even though they don't have much to do.

Cappelli added that companies need to be better at performance management, adding that workers "shouldn't necessarily have to hang around late at night, which is usually the problem to try to impress your boss with the fact that you're working hard."

For his part, Ishbia said United Shore wants employees "out at 6:01 or 5:01, depending on when they're out of there, so they can go be with their families."

However, there is one exception to the "firm 40" policy. When asked how many hours he himself works, Ishbia told CNBC: "a little more than 40, I work more like 60 to 70."

"On the Money" airs on CNBC Sundays at 7 p.m., or check listings for air times in local markets.