Building and Energy Code Updates
Conclusion
Building and energy codes are developed and updated in a very open, transparent, and inclusive process following a three-year cycle. Other standards and programs are recognized by the codes, particularly the IECC, as alternative ways to show code compliance. Updates specific to the 2021 I-Codes address issues related to WRBs in walls that may hold water, such as stucco. The design and specification of glazed entry systems require attention to detail of all of the components to understand the total performance and code compliance. Architects who recognize the interrelatedness of the code development process and day-to-day design and construction work will achieve better understanding of effective building performance and code-compliant strategies.
CASE STUDY
Photos: Geoff Captain
Project: 777 Aviation
Location: El Segundo, California
Project Type: Retrofit
Architect: SOM
General Contractor: W.L. Butler
Glazing Contractor: Glazing Concepts
The Project: 777 Aviation is a three-story Class A office complex that spans 318,182 square feet. Originally designed in 1968 by famed modernist architect Craig Ellwood, 777 Aviation has been reimagined to reflect the needs and culture of today's workspaces.
The Challenge: Because of its iconic status, architecture firm SOM aimed to preserve much of the existing design. At the same time, three important objectives were to increase daylighting, give the building an updated look, and improve overall thermal performance.
Design Solutions: The design goals were accomplished by integrating a grand atrium with a series of large-scale skylights, removing concrete shear walls, and installing high-performance building envelope systems with all-glass aesthetics. The first floor features a new structural-silicone-glazed curtain wall with no exposed exterior vertical mullions or joint fasteners. This produces uninterrupted horizontal glass spans that provide modern, streamlined visuals and a seamless transition to the interior.
New fenestration also includes a glass entrance system that was installed in multiple areas on the building's facade. The system features ultra-narrow 11/8-inch vertical stiles, which produces all-glass aesthetics. In addition, it has the ability to support handle hardware directly on 1-inch insulating glass using through-glass metal fittings. This produces a distinctive floating-on-air look. Like the curtain wall, the entrance system offers streamlined visuals and high thermal performance. Since it minimizes visual hardware, it also allows ample daylight to flow through.
Code Compliance: SOM's design for the 777 Aviation retrofit kept much of the original fenestration on the upper floors intact. In terms of energy code compliance, these systems were grandfathered in and upgraded with high-performance sun control film; however, both the new structural-silicone-glazed curtain wall and ultra-narrow stile entrance system were subjected to California's stringent Title 24 code requirements. As a double thermal system with 1-inch insulating glass, the curtain wall met the performance requirements contained therein. It features a polyurethane thermal break and a unique injection-molded thermoplastic connector that together produce exceptional thermal performance. The glass entrance system features thermally broken framing and cladding with 1-inch insulating glass that together provide U-factors as low as 0.43 to meet code.
"Given the performance criteria for the new fenestration and our goal of having a minimal aesthetic, there was no other option than the ultra-narrow stile thermal entrance system we specified," said Susan Bartley, AIA, LEED AP, project manager at SOM Architecture.
Results: The structural-silicone-glazed curtain wall and glass entrance systems were ideal for the 777 Aviation retrofit because their clean sightlines and minimalist aesthetic do not conflict with the iconic facade that was retained. At the same time, they give the project a fully code-compliant, updated, contemporary look.
Peter J. Arsenault, FAIA, NCARB, LEED AP, is a nationally known architect, consultant, continuing education presenter, and prolific author advancing building performance through better design. www.pjaarch.com, www.linkedin.com/in/pjaarch
