The gut renovation of a 19th century New York townhouse afforded Mark Zeff the opportunity to reinvent the concept of an urban, single-family home. Rear windows were greatly enlarged and ceilings covered in Venetian plaster to welcome in and amplify available the light. (Street-facing windows were limited by landmark regulations.) Furniture is pared down to a clutter-free minimum in the relatively small rooms. The palette is bright an neutral to keep spaces open and airy. Polyester-viscose in a cheerful goldenrod color upholsters a custom headboard in the daughter’s room.