Luxury home builder Toll Brothers saw its second-quarter profit more than double from a year ago, thanks to the niche market it serves, the company's CEO told CNBC's "Closing Bell."

"Our buyers don't have mortgage problems; 20 percent are all cash. Those that get a mortgage put 30 percent down," Douglas Yearley said. "Their decision to buy is more of a discretionary decision, it is more emotional, [and] it is based on confidence ... we love our niche."