Shifting the work culture in the office to better appreciate the value of taking PTO and establishing work-life balance can take time, and it needs to begin at the top of the organization. Why? A quarter of those surveyed by Harris Poll said they were contacted by their boss while on vacation. Managers need to set clear boundaries and expectations of their employees so no one feels like their career success is contingent on them working while on vacation or late every night.

I'm trying to do my part with my own team. For example, when a top-performing employee was preparing for a long overdue vacation, I let him know that if he was going to have any issue disconnecting from work, I would block his email access to force him to disconnect.

The expectation of a constant connection to work exacerbates stress and negatively affects the mental health of employees. With the amount that many Americans work, burnout is inevitable. According to a recent Gallup survey, three in four employees have experienced burnout at work. When employees are overworked, the consequences can be dire—company culture, the quality of work, and employee morale can all collapse. This can quickly spiral into a broader HR problem, with unhappy employees quitting.

Fortunately, the consequences of burnout aren't permanent. Completely unplugging from work can reduce feelings of anxiety, stress, and depression. If business leaders want to avoid the pitfalls of burnout, they should proactively establish a culture where vacation time is respected and protected. There are three simple steps business owners and managers can take:

• Encourage your employees to truly disconnect; make sure they know they should not respond to emails unless its an emergency.
• Institute blackout hours on weekends and overnight; consistent work-life boundaries even during regular work weeks can help employees feel more comfortable going offline while on vacation.
• Lead by example; if employees see leadership at their company making work-life-balance a priority, they're more likely to follow suit themselves.

These steps may seem small, but they can go a long way toward addressing a serious problem. And for those who are concerned that employees being unavailable will hurt the bottom line, don't worry. In my experience, employees and customers alike react well to these boundaries. Responding to emails at midnight on a Friday or on your vacation is rarely their expectation. Don't let it become a habit.

These steps may seem small, but they address a serious problem. If you don't cultivate a responsible culture of disconnecting, you put yourself at serious risk of your high-performers deserting you.

Most employees want to work for a company that cares about their well-being and mental health. If they believe you don't, they will eventually go looking for a company that does.

Brett Derricott is CEO of Built for Teams, which provides HR solutions for small- to mid-sized businesses.

Read more: 

• Coming to NYC: Mandatory paid-vacation?
• Where workers are most, least likely to take advantage of vacation time
• 5 points to consider when designing a vacation policy for your hourly workforce