American studio ISA has used a range of strategies to maximise space, light and views in the metal-clad Signal House, which rises from a slender urban lot.

The multi-level apartment building is located in Philadelphia's Fishtown neighbourhood, a transitioning area that has been attracting creative types and urban professionals.

ISA has created a slender residential tower in Philadelphia

Local firm ISA, or Interface Studio Architects, designed the Signal House to respond to its context, described as "a boisterous mix of elevated rail infrastructure, industrial buildings, late-night bars and restaurants, and busy arterial streets".

"Situated in this visually and sonically loud context, Signal House forms a camouflaged beacon, assertively addressing its surroundings," the studio said.

It is just under 26 feet wide

Built to accommodate singles, couples or families, the 3,500-square-foot (325 square metre) building occupies a site that typically would hold a single-family rowhouse. The site is 32 feet deep (9.8 metres) and just under 26 feet wide (eight metres).

The building's design is meant to "simultaneously draw attention from passersby and provide privacy to residents", the team said.