Prefabrication experiments - 282 - modular city building - 03 - Mat-building

Coined by author and architect Alison Smithson, mat-building, sometimes known as mat-housing, is a modular strategy or system based on the clustering of mass and voids into inhabitable dynamic architectural fields. The mat component denotes a limitless expanse layered over a rigorous planning grid. While not exclusively structural in nature, the grid circumscribes the edifice’s interrelated scale, span and scope.  Mat-housing usually relates to a modular aesthetic illustrated by iconic projects like Paul Rudolph’s Oriental Masonic Gardens, employing building units and volumes as bricks in an interplay of interior and exterior dwelling environments.  Along with the mat imagery, the theoretical ideal of an integrated adaptability and flexibility underscored the most notable example of Mat-building: The Free University of Berlin designed by Candilis, Josic, Woods and Schiedhelm in 1963 arrayed the basic framework of mat-building to define a campus (field in Latin) building that could evolve as needed over time.  The two to three storey scheme projected variability in plan and section across a horizontal plane characterized by a mass / void relationship akin to a Medina or medieval organization connecting public and common areas with more functional spaces for teaching.

 

The material heart of this mat-building was an innovative building system proposed by Jean Prouvé. Le «Tabouret» or stool building system proposed an open plan grid structural system. A square grid of large spanning beams, girders or even space frames determined floor or roof platforms: the open web structural plates were raised over spaced out columns or posts.  Together, the posts and platforms shaped the simple «stool» suggestion. Familiar to other Prouvé projects, a 1-meter grid of steel lightweight panels were proposed as interchangeable parts of the building envelope. The «plan libre» free of any bearing walls made it possible to change the building's interiors, furnishings and even functions over time.  The building as a type of matrix or normalized field made its components both interchangeable and expandable. Its expandability was put to the test in 1997 when Foster and partners were mandated to add a library and undertake a complete restoration. Thirty percent of the removed components were saved and reused as intended by Prouvé’s original structural system. 

Prouvé's open plan «Tabouret» system