Interior designer Honey Collins of Honey Collins Interiors puts her sweet and sophisticated touch on a guest house designed by Patrick Ahearn.

Some houses speak to you the moment you cross the threshold. Others seem to quietly unfold, revealing their secrets one gracious room at a time.

This guest house in Osterville—designed by renowned architect Patrick Ahearn and thoughtfully decorated by interior designer Honey Collins of Honey Collins Interiors—is somehow both. It’s warm and welcoming right away, but laced with layers of detail and intention that invite a longer look.

Although technically a guest house, this new build lives much larger—both in square footage and in spirit. Tucked closer to the street than its primary residence counterpart, on an adjacent lot, yet seemingly part of a shared compound, it was designed with the implied function as a gatehouse, a charming first impression for visitors approaching from the road. “It’s a substantial program,” Ahearn says. “We had to make it feel secondary to the main house, not like a second mansion, and we accomplished that by layering architectural clues that suggest a history of additions over time.”