crossbuilding

Crossbuilding is an architectural arrangement in which two or more building masses intersect, creating a cross-shaped footprint or a network of interconnected volumes. This configuration may be achieved through an orthogonal crossing of floor plates, the addition of skybridges or atria, or by cantilevered segments that extend across a neighbor's footprint. The primary aims are to maximize usable floor area within a given footprint, optimize daylight and views, improve circulation, and foster programmatic integration across functions.

Structural and safety considerations include ensuring adequate continuity of structural frames to carry loads across the crosspoint, managing different foundation conditions, fire separation between crossing elements, and acoustic isolation for adjacent spaces. The form can impact wind behavior and solar heat gain, so facade treatment and shading are important. Construction methods vary from conventional reinforced concrete and steel frames to prefab modules and hybrid systems, particularly when long spans or rapid assembly are required.

Common manifestations include cross-plan layouts where two wings intersect at a central hub, or vertical cross arrangements with floor plates crossing at mid-height to form atria or courtyards. Crossbuilding can also refer to incremental construction where an existing building is extended or wrapped by another mass that crosses its footprint.

Applications are common in urban infill, mixed-use developments, and research campuses, where the cross configuration aids access, daylight distribution, and functional adjacencies. Critics note potential downsides such as complex structural detailing, higher construction costs, and challenges in maintaining uniform daylight across all spaces.