This is a studio design research project I completed while pursuing my masters degree.  It was published extensively in design journals and magazines in the US and abroad.





bottom up, post-fab, architecture :  Let us be optimists


San Juan's uncontrolled urban sprawl and ecological devastation is a tremendous burden for a small island.  The Graft Tower is a regenerative 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.  Additionally there is an eco-tourism hotel and learning center.  A tower at the south end of the site rises 38 floors and contains a vertical farm and living spaces for employees.


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 or farm 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 - which will take place over several decades (figure 01).


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. The Graft Tower uses the concept of grafting and is formally organic in the way similar to the living root structures found in northeast India (fig.02).


The structure is unique in the way it handles its height and introduction of "post-fab" structures.  At crucial structural time intervals the structure is manually hardened in a process done by the permanent residents of the tower 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 - limiting the "upstream" impact and providing jobs for Santurce, Puerto Rico.  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 (figure 03).


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.  The plants grow in the individual units using water conserving aeroponic techniques.  The water that is transpired from the plants can be captured from the humid air and recycled throughout the building, making a self sustaining ecosystem.


Water from the nearby Martín Peña Canal is utilized in the living machine part of the building.  The plants within the growing structure remove the toxic elements from the water.  The final stage of the filtration is within the constructed wetlands around the base of the tower (figure 04).


Living in apartments residents maintain and assist the agriculture of the building.  One crucial task is to maintain the aeroponic networks which grow 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.  (fig. 05) Condensation that is typical problem in the Puerto Rico environment is managed by the yellow "vascular" system.  Certain portions of this 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 island winds for cooling (as typically seen in San Juan vernacular).


The Graft Tower is constructed as discrete components, the unique pod frameworks are fabricated off-site.  By doing so their quality can be controlled to a high level of precision.  This method acknowledges what actually happens in the building process and seeks to eliminate inefficiencies and waste.  The pods (or “blocks”)  made off-site connected to the growing tower.  The pods will navigate into a tower scaffold of with strict tolerance. 


The Graft Tower's main investment is in the structure, it will have been growing for decades even before some new pods are added.  The finishes will be easily changeable as the life cycle of the building is ideally 100+ years.


Regarding the chain management of the Graft Tower, fabrication of the individual pods will take place in Santurce, a distance from the tower measured in blocks.  Many citizens of this area are out of work.  The structural elements are grown from trees and vines that are formed around templates for their general shape.  The main structure has very little embodied energy.  The structure only uses the sun, water, and growing medium to generate itself.  The templates that are fabricated in the neighborhood require a relatively minimal amount of resources.


The nearby Martín Peña Canal has suffered from urban growth without infrastructure to manage waste.  The canal connects the San Juan Bay and the San Jose Lagoon.  The toxins, pollution, and sedimentation in the canal has had drastic implications especially for the San Jose Lagoon.  The effect has been the deterioration of the canal's water quality.


Water from the canal is used in growing the Graft Tower and the plants within the structure, but not within the greenhouses (this would contaminate the crop).  After the water is filtered it can be used by the neighborhood or discharged back into the canal to recharge the system.  To control the environment's humidity and temperature different crops are put into the pods.  Pests are kept outside and fertilizers are not needed.  Within the tower a restaurant in the plinth serves meals made with the crops and a green market sells the produce.  The scraps are recycled as nutrients back into the pod system.



In this self sustaining ecosystem food is grown 24 hours a day, 365 days a year, crops are protected, water is recycled, jobs are provided to local residents, fossil fuel usage is reduced, and there is no agricultural runoff.  The Graft Tower engages and supports these members of the Santurce community and provides a healthy environment for Puerto Rico