By Joshua Bowditch
One65 Main: Sustainability with Style
New architectural capabilities and sophistication are characteristic of One65 Main with the ES-UN8030 glass curtain wall interfaced with terracotta paneling and grille sunshades. The architectural glass-framing supplier ES has product capabilities for practically any climate and design application. In the temperate climate of the northeast United States, versatility to the changing seasons involves minimizing conductive heat loss in the wintertime, minimizing solar heat gain in the summertime, and allowing for opening up to the outside during times of mild weather. Wrapping the building corners are balconies that are accessed by integrated ES-45T swing doors, and portions of the curtain wall are integrated with ES-P7531 operable windows.
Sustainability with ES
Sustainability in the building industry involves the building materials, specifically raw materials, supply chain, and characteristics of the end product. ES is resourceful in procuring basic materials and is unique because it is part of a vertically integrated conglomerate which handles the precursory production stages of aluminum extrusion and glass processing. The implications are streamlining the supply chain and maximizing production efficiency, which correlate to cost savings and overall sustainability.
Preglazed Curtain Wall
The ES-UN8030 is a highly efficient curtain wall system because it has the capacity for large spans of glass, and also because it is preglazed, also known as unitized1. This means the glass is structurally and hermetically sealed (unitized) 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 contaminants2. The silicone sealant Dow Corning 983 is used for structurally bonding the glass to the aluminum frame at the interior side1. Dow Corning 983 is a two-part sealant3; two-part sealants chemically cure within a few hours after mixing2. The size and weight of the dispensing pump required for applying two-part sealants makes field applications impractical2. At the exterior side of joints, Dow Corning 791 silicone sealant is used as a weatherproofing seal1. Silicone sealants are chemically stable and extremely durable with excellent resistance to weathering and aging4. The advantages of a preglazed unitized system include quality control of assembly, exterior side hermetically sealed, and expedited installation. The maximum size for the unitized panels is 5 feet width and 11 feet height2. Continuity of the curtain wall is achieved by joining adjacent unitized panels together with reciprocal framing profiles. The framing system is thermally broken5 to minimize conductive heat transfer. The material of the extrusions for the ES-UN8030 is 6063-T6 aluminum alloy or 6005-T5 aluminum alloy, depending on the component1. Aluminum is lightweight, high-strength, and reflective6, and these aluminum alloys have excellent extrudability7. The exterior aluminum alloy finish is Duranar® Sunstorm® Silver UC70470F in accordance with the PPG Certified Applicator Program
The high-performance glass units are 1” nominal thickness, comprised of 1/4” clear glass with R53/33 coating at the inward surface, plus 1/2” insulating airspace filled with argon gas, plus 1/4” clear glass. The R53/33, which is an acronym for Tecnoglass R-series (Reflective) low-E with nominal light transmittance of 53% and solar heat gain coefficient of 0.33, has a reflective exterior appearance with cool color tones8. During glass processing, the glass is conveyed through a coating machine having a series of low pressure vacuum chambers where the microscopic layers are applied in sequence. The resulting glass is spectrally selective, providing high solar heat control while allowing high visible light transmittance. Argon gas is invisible and nontoxic, having lower thermal conductivity than air. It is used in combination with a low-e coating for optimal thermal performance.
Cladding with Terracotta
The terracotta paneling is LONGOTON® panels manufactured by Moeding in Marklkofen, Germany9. Raw material of high-quality clay is extruded into cross-sectional shape, then by firing at sufficient temperature and duration becomes a high-strength ceramic10. The panels interlock with aluminum support profiles during installation11. The panels are relatively thin at 40mm (about 1-1/2″) thickness and relatively lightweight11, durable, and naturally earth-tone in color.
Aesthetically interesting as One65 Main may be, these aspects 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 ES.
1ES-UN8030 Technical Datasheet. 2018. Energía Solar (ESWindows).
2Takish, 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, pp. 58-65. C. J. Parise (ed.).
3Dow Corning Americas Technical Manual. 2002. Dow Corning Corporation.
4Beall, C. 1999. Thermal and Moisture Protection Manual. McGraw-Hill.
5Architectural Guide. 2020. ESWindows.
6Aluminum Extrusion Manual, 4th edition. 2014. Aluminum Extruders Council.
7Davis, J. R. 2001. Aluminum and Aluminum Alloys. Page 351-416. In: Alloying: Understanding the Basics.
8Low-E Series. 2019. Tecnoglass
9Moeding Catalogue. Moeding Keramikfassaden GmbH.
10LONGOTON®-Clay-Tile Facade. 2006. Moeding Keramikfassaden GmbH.
11ift Rosenheim GmbH. 2022. Alphaton and Longoton Ceramic Facades, Environmental Product Declaration EPD-MFA-GB-48.0. Moeding Keramikfassaden GmbH.
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. Read previous article.