The Ground Breaker Construction sites don’t exactly encourage high style—unless you count a hard hat as a must-have accessory. “When I get home, I need to wear something nice,” says Nima Nakhshab , who runs S.D.’s pioneering Nakhshab Development + Design (nddinc.net) with his older brother, Soheil. “It just makes me feel good.” The Dwell -featured design-build firm just finished a laid-back Encinitas looker with elements of European style for a Belgian couple who owns a clutch of SoCal boutiques. They’re also hard at work on a 17-unit contemporary eye-catcher in Golden Hill. “We’re hoping all our friends will move in,” he says. When he’s not traveling the world—he recently explored Europe and Thailand solo— Nakhshab hangs out at Union4, the NDD-designed multigenerational digs in Bankers Hill where the brothers live with their parents and Soheil’s young family. “We all have our own places, but it still gets very crowded,” laughs the bachelor, who almost became a musician, until his dad reminded him he’d likely end up broke—a sure style-cramper for a guy who recently went window-shopping for a “someday” Omega and favors a classy look with a pocket square-size pop of color. “The lines of a well-made suit are flawless,” he says. “You can relate that back to architectural design. Everything has to be perfect.” OUTFIT Windowpane suit, $1,525, by Paul Smith; shirt, $435, by Etro; cashmere sweater vest, $795, by Brunello Cucinelli; skinny tie, $105, by Theory, all at Neiman Marcus, Fashion Valley.