Graft Tower [liblabdesign.com]
bottom up, post-fab, architecture : Let us be optimists
Site: Santurce, San Juan, Puerto Rico 18° 27' 10" N 66° 4' 43" W
San Juan's uncontrolled urban sprawl and ecological devastation is a tremendous burden for a small island. The Graft Tower is a net plus resources building that not only provides water, food, and energy for the neighborhood, but brings in revenue which subsidizes the building and many needed new jobs in Santurce.
The building is located on New Monteserrate street at the intersection of San Juan's two arterial public transportation routes. The program on the ground levels is an epicenter of commercial activity and services to support the light rail hub. A tower at the south end of the site rises 36 floors and contains an eco-tourism hotel and apartments.
Construction of the building is unprecedented in its materials and methods. This provides the project with a new language of an interlaced meshwork of structural columns spiraling into the sky with connecting fingers spreading out to the new plazas below. The structure is literally grown by grafting inosculate fibers around the basic skeletal frames of the commercial and housing units. As the organic material spreads upward and around the frames more are brought from off-site and placed by a mobile crane as necessary - the post-fab process continues.
Feeding off sunlight and rainfall the organic structure follows its own logic as it moves up and around the frames, often branching off and spreading sporadically before it is grafted back to the main structure or finding programmatic frames. At crucial structural time intervals the structure is manually hardened in a process done by the permanent residents and is then wrapped in a carbon fiber reinforcement. So that the tower can continue to rise, root stock grafted into the upper portions of the structure before the lower portion is hardened and wrapped with the carbon fiber structure. The structure will then continue to organize itself as it winds up the individually designed frames.
The frames are designed and fabricated in a nearby shop. As the frames move upward their design is increasingly influenced by the prevailing western winds. Optimizing the frames design for natural ventilation and cooling creates a twisting tower with each pod shape stretching toward the west (as determined by wind dynamics).
Water is collected at the bottom of each pod that is formed by the frames, carbon fiber structures, and infilled skin. The water is then dispersed throughout the open framework into the vertical farming that grows throughout. The plants grow sporadically throughout the changing building as they are able to find water and sunlight.
Living in apartments residents maintain and assist the agriculture of the building. One crucial task is to maintain the hydroponic network which also grows as the building does. This unique multi-purpose meshwork is highlighted in a yellow-green carbon fiber reinforcement. The yellow mesh not only is structural for the skins panels, but distributes water throughout the tower, and manages temperature of the panels themselves. Condensation that is typical problem in the Puerto Rico environment is managed by the yellow "vascular" system. Certain portions of the vascular system also distribute liquid ethanol, a product of the artificial photosynthesis skin panels, which fuels the energy demands of the building. The faceted skin allows a large variation in the electrochromatic vision panels.
The stewardship of the building's structure and vertical farming is subsidized by the eco-tourism hotel. Residents and visitors access the tower through open vertical and horizontal circulation systems, taking advantage of the islands winds for cooling and not having to mechanically manage this part of the building's environment (as typically seen in San Juan vernacular).
The network of organically responsive parts make a entirely unique building as a whole which engages and supports the Santurce community.