As a child, Steven Humble was "enthralled" by the hidden doors and secret passageways he saw in adventure movies like "Indiana Jones and the Last Crusade."
So Humble used his training as a mechanical engineer to turn his childhood fascination into a successful business that's made him a millionaire.
As founder and president of Creative Home Engineering, he designs secret doors "just like the ones in movies, but for real people," he says on CNBC's "Blue Collar Millionaires."
The doors Humble builds lead to secret storage rooms or bunkers, and are designed to look like full-length mirrors, fireplaces, brick walls or, in some cases, things you might not expect to find in a home, like fake telephone booths.
The idea for the business came to him shortly after he graduated from college. Humble had a job designing medical devices, but felt frustrated by what he was earning and decided he wanted to do more with his mechanical engineering skills.
"I had designed this product that made my boss a ton of money and I feel like I am just stuck in this cubicle," he says. "I thought, 'Surely I can do that. I have that skill set.'"
So in 2004, he left his job and started building secret doors. Business was slow at first and Humble worked from his bedroom.
But word spread about his innovative designs, and Humble's risk paid off. Last year, his company made approximately $1.2 million in revenue. The engineer lives in a million-dollar home near Phoenix, Arizona, and drives a Corvette.
Creative Home Engineering builds about 150 doors per year, ranging in price from $2,500 to more than $100,000. The business may see a boost in demand from the increasing number of wealthy people who are prepping for the end of the world.
"Money really isn't the driving force," he says. "I'm driven by making the best product that I can make."
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