Before beginning their retrofit of this Boston condo, the homeowners camped in a tent in the unfinished space, observing the light throughout the day and determining their desired patterns of use. In spite of the folding chairs provided, they observed that someone was almost always perched on the 6″ window sill. The design evolved from there, beginning with sill extensions that provide a continuous window seat from which to enjoy the views of downtown. While the one bedroom was sufficient for normal usage, the couple wished to accommodate impromptu visits from their two adult children, so we engaged a spatial “dead zone” near the entrance with a cabinet enclosing two sleeping berths. Just as in a yacht, each boasts its own lighting, storage, and privacy curtain. Other custom details include a bed that slides over built-in cabinets to create a space for yoga, and office shelving and a convertible foldout desk made from folded sheet aluminum.