Sarphatistraat Offices Steven Holl Architects Amsterdam, Netherlands 1996-2000
Sarphatistraat 430 1018 GW Amsterdam The Netherlands
Double-Skin Envelope Copper
Stucco
Perforated prepatinated screen sheet
Gossamer-optic painted collage wall
Composition
Raw Material Extraction
Mine
Copper ores are extracted from open-pit copper mines
Portland cement
sand
water
Coat Layering Process Mill
Ores are beneficiated, or separated into mineral and gangue, and finely crushed and ground
Lath
Wire mesh lath is first added in order to attach to main structure and provide reinforcement for added strength
Scratch
Smelt
The ground ores are roasted and then matte is produced by heat and a carbon reducing agent in a furnace
The scratch coat is the first layer to be applied, consisting of cement and sand. A trowel is used to create a key for the second layer and the scratch coat is to fully dry before the brown coat is applied
Brown
The second layer, called a brown coat, consists of sand, cement, and lime and is leveled to provide a smooth, even surface for the third and final coat to be added; this layer is to be cured for 7 to 10 days before the finish coat is applied
Refine
Matte is converted into blister by the removal of sulfur at a high temperature. The copper is then refined by electrolysis.
Finish
The outermost layer of stucco is the finish coat, which is either a mixture of sand, cement, and lime or an acrylic-based coat, both of which can be mixed into a variety of colors
Panel Fabrication Patina
Cupric nitrate adds a chemically-induced patina to the copper which produces a blue-green coloration to the panels
Wall Section
Roll
Copper is forced through rollers until 4mm thickness is achieved
Punch
Copper sheets are perforated with punch force and die; round holes are arranged in a staggered pattern
perforated copper panel
Unit: Panel
3.20 ft
custom tee
6.56 ft
punched aperture
System Components
Unit to Unit @ face
double-glazed window
Copper sheets are bent at panel connections, creating a slight reveal along the grid lines; each panel is independent of each other
metal strut
Unit to Unit @ corner Panels at corner conditions are bent and wrapped as to overlap each other and are then bolted together, creating a seamless transition from faรงade to faรงade exterior stucco finish
Unit to Secondary Each panel is bolted to a steel connector plate as part of a custom tee, which is welded to a metal strut
Unit to Primary The panels are arranged on a grid that aligns with a gridded metal strut system that is connected back to the primary steel frame structure