Building Blankets — Joshua Chiang

In the post-World War II construction boom, changes in zoning regulations and the widespread use of air conditioning led to the design of sealed glass and steel towers. The Lever House (SOM, Gordon Bunshaft and Natalie DuBois) was the first skyscraper with curtain wall system upon its completion in 1952. While it was the first lightweight facade construction, the building had significantly inferior thermal/insulation performance compared to previous buildings. The facade of Lever House has a U-value of approximately 3.3W/m2k, compared to 2.6W/m2K for the Empire State Building. Problems arose from this system—internal spaces experienced vast heat loss in the winter and overheated from excess solar gain in the summer.
In response to these problematic conditions, the design team proposed to fold the curtainwall. Altering the angle of the existing flat and thermally inefficient facade system to would introduce shading to reducing solar heat gain and create an intermediate space for passive ventilation.

Direct Sun Hours Analysis

30° angle

35° angle

45° angle

Facade Design

Axon Section

Detail Section

Material Specifications
The selected materials form a lightweight skeleton that projects off the existing building facade. The operable shade diffuses direct sunlight, enhancing the usable interior space. The overlapping system implements self-shading to reduce heat gain during summer months.

1 Vitro Solex spandrel panel
2 Vitro Solex glass
3 UPN 160 steel channel
4 Custom aluminum profile
5 HE 160 AA beam
6 Roller shading system
7 Roller track
8 Steel framing
9 Insulated aluminum panel

10 Cement parging
11 CMU block
12 Cellular insulation
13 Steel flashing plate
14 Concrete floor slab
15 Fireproofing
16 Acoustical tile ceiling
17 Steel decking
18 Double-leaf window

Building Elevations

North

East

South

West

Software:
Rhinoceros 3D
Ladybug
Adobe Illustrator

Special thanks:
Rodrigo M. M.