GUY TALK: Growing demand for weathered wood opens the door for rapid expansion by an enterprising former engineer.

• Author: Cranford, Steve

One of the proudest moments in Zac Guy's life came when he paid the tuition bill himself for his freshman year at N.C. State University. He could cover the check with proceeds from a business he had chanced upon in high school: Selling bam wood for cabinets, flooring and other uses. At State, where he double-majored in chemical and paper-science engineering, he continued to oversee the business, making the 263-mile drive from Raleigh to his home in Waynesville on weekends. He had four or five employees, and Saturday was payday. He'd discuss their assignments, attend church on Sunday morning, then head back to school.

By graduation in 2001, Guy's business grossed more than $125,000 a year. For many young entrepreneurs, that may have been a clear signal, but Guy opted instead to treat the wood business as a side hustle. He worked in engineering at a pharmaceutical plant in Ohio, a state he describes as "a barn-rich environment" that allowed him to source more wood.

He then moved to a job at a medical-supply company 75 miles from Waynesville, working the third shift so he could run the wood business during the day. Guy's wife, Haley, would sleep in their pickup while he worked, and they would visit clients two or three days a week after his night shift ended. "I'd pull a Superman in a McDonald's bathroom and come out in a suit and tie," he says. "I'd sell wood and then go to sleep in the truck while my wife drove us home."

The two-job lifestyle continued when Guy took an engineering position at an Epsom salt plant in Waynesville before he decided the Superman routine was getting old. After giving six months' notice, training his replacement and consulting at the plant for a year, he turned to wood as his full-time effort in 2004, when annual revenue totaled about $750,000.

This year, Appalachian Antique Hardwoods LLC is on track for $7.5 million in sales, about triple the 2016 results, says Guy, who turns 40 in January and co-owns the business with his wife. "I borrowed some, but not a lot," he says, initially using his engineering salary to pay most expenses.

What he discovered in high school was that premium builders love the striking appearance of old boards and beams. His first sale, for $1,300, came from a load of American chestnut, a once-common species wiped out by a blight in the early 20th century. Barn-makers preferred the lumber because of its rot resistance, while woodworkers prize its distinctive worm holes and warm colors.

Guy...