A thoroughly transformative re-design by New York studio O’Neill McVoy Architects turns a historic red brick townhouse on a slender 24- by 76-foot lot in need of light and air into an ultra-bright and inspiring modern residence for a young family. The Clinton Hill Courtyard House, in a landmarked section of the neighborhood, was built in 1877 as a carriage house for the mansion next door. The historic integrity of the home’s exterior was left intact, but inside, three strategic openings–including skylights, a central courtyard, and a perforated interior stair wall–were created to let in light and air everywhere for daily living.