PO 1.9 Prefab Parametric

Parametric Design

  • “In parametric design, it is the parameters of a particular design that are declared, not its shape…Equations/Rules can be used to describe relationships between objects, thus defining an associative geometry.” - Branko Kolarevic

  • “Parametric expressions, therefore, allow users to change the values of key parameters, and to observe the propagation of changes on dependent expressions, and hence upon the dependent geometry. This is often referred to as strategic manipulation.” - Peter Szalapaj

  • The relationship between the three-dimensional digital models and the built environment it is based upon is the output information between the computer and the automated fabrication devices. This output is achieved through digital code and is referred to as CNC or computer numerical control.

  • The use of digital fabrication techniques in architecture allows for greater diversity in building form, detail, and proportion. Advocates for digital design argue that these fabrication techniques provide a combination of creative solutions achieved at a similar efficiency to mass-production. It is argued that the digital fabrication overcomes the repititiousness of modernity without a loss of productivity. This process is often referred to as “mass-customization”.

Make Magazine

  • Magazine about parametrics

  • covers projects, stories, and new technologies

Methods of Modification

  • Additive Processes

  • Subtractive Processes

  • Bending Processes

SLA

  • Stereolithography Apparatus

  • Layers of liquid metal hardened by UV light

  • 3D Printing Process

SLS

  • Selective Laser Sintering

  • Uses a laser to sinter powder based materials together, layer-by-layer, to form a solid model

  • 3D Printing Process

FDM

  • Fused Deposition Modeling

  • Molten thermoplastic is extruded through a nozzle to build objects layer-by-layer

  • 3D Printing Process

The Porter House

  • 2003, New York

  • Renovation and conversion of a 6-story 30,000 sq. ft. warehouse into residential condominiums

  • Gregg A. Pasquarelli - SHoP Architects

  • A new 20,000 sq. ft. addition added 4 stories to the existing building and an 8-foot cantilever on the south facade

  • There’s a shared boundary between the original Renaissance Revival facade and the new addition

  • Custom zinc panel system for the facade and floor-to-ceiling windows in the new addition

  • Metal framework of the addition is clad in ANTHRA-ZINC

  • Custom-designed, laser-etched zinc metal wall panel cladding system

  • Zinc rain-screen emerges from a family of 15 profile types, from which there are 150 different profile versions, yielding 4,000 total panels

  • Variations achieved by cutting and bending each profile panel type differently

  • Creators were going for an ambience of complexity and randomness, to fit in with the existing environment

  • The use of BIM achieved huge gains in fabrication and installation times

  • Elevation pattern based on the most efficient layout of panels on a standard width of sheet metal

  • Accuracy in the production of the varying panel elements and efficiency of material use

  • Standard zinc sheets of 39”x118”

  • Program team worked closely with the material fabricator to minimize material waste

  • Software was standard to the sheet metal industry

  • Panels were folded and cut directly according to the SHoP digital files

  • Highly customizable look with various panel sizes

  • Vertical light boxes draw pedestrian eyes upward and give a sense of lightness to the addition, especially at night

  • 3,800 piece jigsaw puzzle

Mulberry House

  • Nolita District, New York, 2008

  • 9 residential condos

  • Required a primarily brick exterior to match the neighborhood

  • Typical brick construction using masonry veneers and ties

  • Precast system

  • Uses a Flemish Bond layout

  • Elevation geometry is in multiples of brick dimensions

  • Precasting saves labor costs and time on site

  • Each brick is offset 3/4” from its adjacent brick

  • Grid of 6 squares in a 3:2 proportion

  • Everything along the facade conforms to this proportional pattern

  • Low to high to medium points

  • Produce undulation and visual interest

  • Pattern breaks down into 8 different precast elements, each being a portion of the overall geometry

  • Staggered pattern of alternating elements

  • Addition of a tapered vertical fin to the window opening and sill above

  • Precast building ends up being much more complex than a simple precast element

Mulberry House Prefabrication

  • Each precast element created from a mold

  • Special bricks are designed to be held in the mold and cast into concrete panels, with anchors on the inside face

  • Molds arranged so that the corners look like full bricks

  • Maintains a Flemish Bond

  • Concrete poured to the mold’s brim

  • Concrete sets between the anchors of the brick veneers

  • Mold designed through digital fabrication and CNC routed

  • Synthetic mold surface positions the brick and releases the precast concrete without adhesion

  • Allows concrete to get between the bricks and create a visual false mortar

  • Tapered section is a mold extension, allows the accomplishment of the adjacent fin

  • Sill is more complicated as the protrusion beyond the precast face makes it extremely difficult to include in the mold

  • Sill is molded separately and bonded to the precast element after it has been removed from the mold

  • There is no indication line of the sill addition in the assembly process documents

  • There are voids in the mold to reduce the overall weight of these hanging concrete pieces

  • Steel anchors are embedded into the precast concrete to attach the facade pieces to the building

  • Prefabricated pieces are eventually lifted and attached to the building, resulting in the rippling facade

  • Gaps between pieces express the construction process by slightly revealing the prefabricated individual pieces

  • Maximum undulation and minimum weight to concrete