- Channel (U-Shaped) Glass
- New Construction
- Educational & Museums
- Lancaster, PA, USA
- Completion Year
- Approx. Surface Area
- 6,000 sq. ft.
- Steven Holl Architects
- National Enclosure Co.
The three-story, 33,000-square-foot building curves in both plan and section, responding to several large historic trees on the site. Eight helical-curved, double-glazed channel glass walls by Bendheim clad the building’s 2nd and Mezzanine levels and define its celebrated “box-kite” shape. One of the main challenges for Bendheim was to engineer a unique “parallel, single-glazed, tip-to-tip” framing configuration for the 16-foot tall curved glass walls. The unusual layout – never before done on an exterior application in the US – was conceived to minimize the channel glass joints’ visual appearance. Together with the use of translucent white insulation and ultra-clear low-iron channel glass, it produces a homogenous facade featuring a crystalline brilliant white aesthetic.
Channel glass joints create its signature linear aesthetic. The flange cluster is typical in traditional double-glazed applications, where four glass flanges meet – the interior and exterior channels, plus the adjacent channels. Emblematic of Steven Holl, the architect took a building material he’s often used on projects and made it brand new. Holl’s tip-to-tip channel glass facade configuration at Franklin & Marshall de-emphasizes the joints and creates walls with deeper cavities, allowing the insertion of double-thickness insulation. This enhances the thermal performance of the wall and the diffusion of natural daylight. During the day, the helical-curved channel glass walls diffuse approximately 20% of visible light to the interior, eliminating glare – ideal for light-sensitive art studio environments. At night, they emit a subtle inner glow.
The project was completed on time and on budget. Holl employed several budget design strategies:
- His curved walls are more cost-effective with the channel glass than flat glass, as only the frames are custom curved; the 10”-wide channels are segmented within the frames
- He worked closely with our team to maximize the use of more cost-effective stepped channel glass planks in the mezzanine arches – as a result, only a fraction of the channels required more expensive custom angle cuts
- The use of relatively lightweight ¼”-thick channel glass was a benefit to the structural demands of the project, as the top two channel-glass-clad floors cantilever dramatically over the base of the building
- The highly energy-efficient, double-insulated, daylight-friendly channel glass contributes to the building’s LEED Gold design and operational energy savings
Bendheim’s low-iron 504 Rough Cast textured channel glass is fabricated by Glasfabrik Lamberts using an energy-efficient glass melting furnace, powered by a clean mix of oxygen and natural gas. The rest of the production facility runs on 100% renewable electricity. The low-iron channel glass features 15% to 25% post-consumer recycled content (see EPD).