Amidst the iconic early 19th century brick row buildings of downtown Portsmouth, the 111 State Street rehabilitation includes the construction of a new rear infill addition, connecting four adjacent structures. The addition serves life safety egress and accessibility improvements. Facades of the existing building are restored to original materials and fenestration styles. Structural deficiencies are corrected with framing reinforcements and select replacements. A deep energy retrofit improves the building envelope, mechanical systems and energy efficiency, for continued mixed use occupancy with restaurant at street level and residential use above.