House O, designed by Jun Igarashi, forgoes hallways and interior doors in favor of casually interconnected rooms.

When Pablo Pérez Palacios’ Mexico City–based architecture firm PPAA was tasked with building an apartment tower to meet La Colonia Roma's need for additional housing, he faced a problem familiar to developers in historic neighborhoods everywhere. The site was occupied by a dilapidated home that dates to 1925, and local laws required that the facade and part of the structure be maintained. PPAA’s innovative approach was to cut the original three-story home in half, preserving enough of the building to front the street and hold two apartments replete with classic Victorian details like high ceilings and restored millwork. In the back of the lot, they designed a sleek eight-story apartment tower that would hold an additional nine apartments, for a total of 11 units. Not bad for a site that was previously an uninhabited single-family house.

Sleeping nooks that look like the grooves in a block of cheese.

A passage between the walls for hide and seek.

For PS 234 in Manhattan's Tribeca neighborhood, Macrae-Gibson designed a colorful walkway to connect the main school building to a modern addition designed by the firm in 2008. The walkway, adjacent to a play yard, protects students and teachers from the elements as they move from one area to another.

The red steel-framed structure is lined with perforated metal panels in a variety of colors.

The addition’s two stories of cedar-framed sliding doors and window provide generous views of the house’s prized jacaranda tree. The addition’s polished concrete floor and white cladding extend into the garden, drawing occupants to the serene rear porch. There, they can relax on stools designed by Alvar Aalto and Charles Wilson while admiring the luscious greenery.

A vibrant yellow pocket door adds a playful splash of color in the bathroom/laundry area on the lower level.

The bar showcases many green products. The bar top, made at the 19 greek street gallery, is fashioned from recycled glass, and the chairs, from both Out of the Dark and Studio deForm, are fashioned from upcycled material.

Another view of the mezzanine. Rough brick walls add texture and old-world charm.

According to Ndoro, LIBRARY will “provide a much-needed space for the pioneering design community of the capital and beyond.” This room features a collection of eclectic Middle Eastern and African pieces, according to 19 greek street founder and creative director Marc Peridis. The curvaceous M'Afrique Shadowy Chair by Moroso is made by Senegalese craftsman, the rug and vases are fashioned from recycled African fabric. The two Papillon chairs near the window are by Karen Chekerdjian, a designer based in Lebanon.