Wrapped in modern, curved aluminum curtain wall and capped with an illuminated crown, the residential tower of 465 North Park Apartments attracts the eye like a shining reflective beacon. The building, located in Chicago’s Streeterville neighborhood, encompasses 588,000 sq ft, offering 444 luxury rental units, two amenity levels, and 11,650 sq ft of retail/commercial space.
The new apartment building’s curvy, jewel-like exterior was designed by Pappageorge Haymes Partners. To help meet the project’s specified aesthetics, while achieving thermal performance, durability, and sustainability, the materials for the curtainwall were carefully chosen. The property is pursuing Gold certification through the U.S. Green Building Council’s LEED® rating system. Therefore, the architects chose EFCO Corporation to provide curtain wall materials. EFCO, headquartered in Monett, Missouri, is a leading manufacturer of architectural aluminum window, curtain wall, storefront, and entrance systems for commercial architectural applications. EFCO relied on a combination of Technoform‘s polyamide thermal barrier and plastic hybrid stainless steel (PHSS) warm edge TGI®-Spacer M.
Curving Aluminum Curtain Wall
To create this new, modern, architectural icon that curves into two angled ellipses, building developer Jupiter Realty Company said it “challenged a team of inspired designers and proven advisors to create a place that’s special. A place that makes its residents feel special. The result can be seen in every detail. The sensuous curve of our glass curtainwall — inspired by aspen leaves — maximizes views from every residence. Inside, our gracious spiral staircase — designed to evoke a nautilus shell — creates a warm and welcoming lobby.”
For the building’s first and second floor lobby and main entrance, EFCO provided nearly 12,000 sq ft of 5600 aluminum curtain wall. The above-ground parking garage was enclosed with approximately 9,000 sq ft of the company’s 8750 unitized curtain wall. More than 5,000 windows and 200 doors were installed using EFCO’s window wall, and Terrastile doors on the tower balconies.
EFCO and Technoform have a long history of working together, as the company has been using Technoform thermal barrier products since 2006. “Technoform’s durable, warm edge spacers and thermal barrier strips allow our products to provide outstanding thermal performance without sacrificing structural integrity,” said Josh Wignall, EFCO’s director of marketing. “For example, our 450X windows use both Technoform’s thermal break and thermal spacer to offer industry-leading measured performance as high as 75 for condensation resistance factor (CRF) and a U-Factor as low as 0.24.”
In addition to reducing condensation and improving thermal performance, the curtain wall achieves a Sound Transmission Class (STC) rating of 30 or higher, contributing to the acoustic comfort of the apartment’s residents. The curtainwall’s pre-glazed insulating glass contains Guardian SunGuard® AG 43, which was inserted into the aluminum framing material under quality-controlled facility conditions. The low energy, high aesthetic glass reduces unwanted solar heat gain, while maximizing natural light.
Technoform’s PHSS warm edge spacer and polyamide thermal barrier strip also contributed to the project’s appearance. Specified in gray, the TGI-Spacer M’s color blends seamlessly with the gray-toned glass and finished aluminum. The thermal barrier also made it more economical to use dual finishing techniques. On the apartments, the glazing systems’ aluminum framing has different finishes on the interior and exterior: A mica coating in a “Silver Burst” color was applied on the exterior and Class 1 clear anodize on the interior.
Meeting LEED certifications
Pete Dyer, EFCO’s regional sales manager, recognizes how the use of aluminum helped meet the “green” goals of the project. “The finishes enhance both the aluminum’s aesthetic and its durability. The aluminum also contributed to the project’s sustainability goals,” he said. “The aluminum billet for EFCO products are sourced from within one mile of our manufacturing facility, and all the aluminum used by EFCO includes pre- and post-recycled content.”
Construction began in the summer of 2016 and its façade was completed as scheduled and within budget. The first tenants moved in during Aug. 2018 and as of October 2019 there were still a few apartments available for lease. The luxury apartment building overlooks the Chicago River downtown, surrounded by monolithic skyscrapers, and views of Lake Michigan in the background.
“The tower’s glazing flows to the base in a distinctive form, further enlivening the active Illinois Avenue entertainment and retail corridor,” described Pappageorge Haymes Partners. “Distinguishing itself from its context, the floor plan is derived from two angled ellipses that slide apart, permitting a conventional floor plan that beguiles the organic shape, orients windows toward select view corridors, and creates a striking presence.”
On the interior, the one and two-bedroom residences are furnished with modern fixtures and refined finishes. The convertible layouts (open floorplans) feature city or lake views from most points in the room from the kitchen, with light pouring in from the living room’s floor to ceiling windows. Sparkling new stainless appliances, elegant cabinets and sleek countertops, complete the contemporary aesthetic.