This proud row house faces Prospect Park, but its last owner had turned the building into chintzy B&B suites. To reorganize rooms to suit a growing family while preserving period details, the architects took a surgical approach to the design. They not only wove state-of-the-art building systems through the historic structure, but replicated the original stone, woodwork, and stained glass. New soapstone slabs and inlaid floors crisply contrast with old filigree for a striking new kitchen. A new outdoor stair connects two new roof decks.