By Joshua Bowditch
Architectural Stewardship: One Thousand Museum (Miami)
Floor upon floor of glass systems arranged among curvilinear exterior columns, which architecturally can be referred to as ribs, is the feature of One Thousand Museum in Miami. In effect the ribs provide structural buttressing simultaneously with aesthetic interest along the entire height, but by far, the exterior is primarily glass. In terms of sustainability, high-rises can require massive quantities of concrete. Especially in Florida, the derivation of constituent materials in concrete is a significant environmental concern. Therefore, the use of concrete is offset with expansive glass systems.
One Thousand Museum has preglazed glass systems by ESWindows, mainly the ES-7100, a highly efficient preglazed window wall. In this context a system is the framing, made of aluminum extrusions, that holds the glass. These systems are design-engineered to allow for expansive glass panels with the capacity to withstand high wind pressures and impact of projectiles, and to have efficient closure at the joints to prevent intrusion of moisture into the building envelope. The term “window wall” refers to aluminum-framed glass panels that span between floor slabs. As a “preglazed” system, the glass is sealed to its aluminum frame at the factory as opposed to on-site, so that the sealant is applied and cured in a controlled environment, where there is no variation of temperature and humidity, and no exposure to airborne contaminants1. It is also known as a “unitized” system referring to the preassembled unit. Dow Corning 791 is used as a weatherproofing seal at the exterior side glass to aluminum interface2. Silicone sealants are extremely resistant to weathering with excellent heat and UV resistance3. The advantages of a preglazed system are threefold: quality control of assembly, exterior side hermetically sealed to prevent moisture intrusion, and expedited installation. Sliding glass doors with matching glass and aluminum finish are ES-6600, which are also preglazed.
ESWindows is vertically integrated with other subsidiaries and the products are assembled in the same manufacturing complex as processed glass operations and aluminum extrusion production. This consolidation maximizes coordination efficiency and streamlines the supply chain. These other stages of production, specific to One Thousand Museum, are briefly described.
The material of the extrusions for the ES-7100 and ES-6600 is 6063-T6 aluminum or 6005-T5 aluminum, depending on the component2. The designations refer to the composition of the alloys and the temper. The exterior aluminum finish is Duranar® Cosmic Gray Mica, in accordance with the PPG Certified Applicator Program4. Duranar® is a fluoropolymer finish meeting AAMA 2605 performance standards, which is the highest level of durability among exterior grade finishes for aluminum alloy extrusions. In the coating process, the extrusions are pretreated and the coating is applied as electrostatic liquid spray to the extrusions, then cured at specified temperature. Aesthetically, fluoropolymer finishes are glossy. The darker gray color finish, along with the gray glass, contrasts with the white rib-like columns.
The high-performance glass units are 1-5/16” nominal thickness, comprised of three plies of 1/4” glass; specifically, one ply of 1/4” gray glass, plus 1/2” airspace, plus two plies of 1/4” clear glass with a laminate interlayer. The gray glass is inherently tinted glass, containing raw material of soda-lime-silicate with additive metal oxides that function as colorants and control the transmittance of heat and light. It absorbs solar heat before emitting it to the outside or inside. The gray tinted heat absorbent glass is positioned at the exterior side so that the heat is dissipated to the outside most efficiently, and at the inward side, the heat dissipates to an insulating airspace.
The use of expansive glass systems is a factor to sustainability. Glass allows natural light which is not only a light source, but is also psychologically beneficial to the occupants. The glass is inherently tinted, providing solar heat control and aesthetic effect. Glass is produced efficiently from abundant and readily available silica sand. Glass is impermeable, which is an invaluable characteristic in the hot and humid climate.
Aesthetically interesting as One Thousand Museum may be, these aspects described would be generally unknown. It is publications like this one that can provide representation of these sustainability aspects through description and illustration. That would be the intent of “Architectural Stewardship”.
This article of Architectural Stewardship was sponsored by ESWindows.
1Takish, M. S., M. H. Haugsby, C. M. Schmidt, and W. J. Schoenherr. 1989. Structural Silicone Sealant Curtain Walls: Field or Factory Glazing? In: Science and Technology of glazing Systems, ASTM STP 1054, American Society for Testing and Materials, pages 58-65. C. J. Parise (ed.).
2ES-7000/ES-7100 Technical Datasheet. 2016. Energia Solar (ESWindows).
3Beall, C. 1999. Thermal and Moisture Protection Manual.
4The Power of quality. 2022. Tecnoglass.
About the Author: Josh Bowditch
As a native resident with architectural experience and environmental regard, Josh Bowditch is intent on publishing about sustainability in the architectural and building construction industry locally. From being in the architectural profession, Josh has an understanding of the processes involved. Is it possible to reconcile environmental considerations with development? The word sustainability has various connotations but indeed can be viewed in the context of stewardship.