There’s nothing but light coming into this three-bedroom loft co-op at Ruggles House, a Gramercy Park building located at 112 East 19th Street. Ruggles House was built in 1913 as an industrial loft building with high ceilings and huge windows. When it was converted into a residential building, only two apartments were put on each of the 12 floors. The result at this particular unit is a sprawling floor plan with those old industrial interior details. It is currently on the market for $3.5 million.