Rethinking building enclosures: Pushing boundaries with EIFS technology

by tanya_martins | February 15, 2025 3:29 pm

By Daniel A. Canova

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The Atrium at Sumner, an 11-story affordable senior housing project in Brooklyn, N.Y., exemplifies how exterior insulation and finish systems (EIFS) can be used to achieve high-performance building enclosures. As a new construction project under the NextGeneration New York City Housing Authority (NYCHA) initiative, the development aligns with Passive House standards, delivering exceptional energy efficiency and sustainability.

This case study explores how EIFS was instrumental in meeting these rigorous performance requirements while addressing the unique design and construction challenges for affordable housing.

Built to the highest energy standards

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NextGeneration NYCHA is proactive about creating sustainable carbon-neutral housing. Recognizing the inefficiencies of older buildings under their management, which often have little to no insulation, the initiative set out to construct the Atrium at Sumner to high standards and the highest energy standards globally—Passive House standards.

Passive House is the world’s leading standard in energy-efficient construction. The Atrium at Sumner meets many of the Passive House requirements, including the requirements for airtightness and thermal control in the building envelope, through its significant green and energy-efficient features, which include 101.6-mm (4-in.) expanded polystyrene (EPS) insulation. All the EIFS components are adhered, no fasteners are used—eliminating any risk of thermal bridging. All features will result in 60 to 70 percent lower energy consumption for the Atrium at Sumner than for the average New York City apartment building. The physical design of the building also plays a role in energy savings.

EPS insulation, like that used in the Atrium at Sumner project, typically has an R-value of approximately 4 per inch, providing effective thermal resistance. Its closed-cell structure enhances its moisture resistance and long-term thermal performance. Sustainability aspects include its ability to be recycled, lower embodied carbon footprint due its light weight and its energy efficiency over its lifecycle, significantly reducing energy consumption and associated carbon emissions.

Design specifics

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The NYCHA chose Studio Libeskind, an international architecture firm headquartered in New York City, for the project. As the Studio’s website notes, “We believe that bold design must be realized with sustainable technology,” a philosophy that aligns with NYCHA’s goals.

Studio Libeskind wanted to create a space that enhanced the residents’ quality of life. The design features a dynamic yet rational geometric form punctuated by open and solid elements. The design team aimed to interact actively with the street and the surrounding context. Bold diagonal lines wrap the building at angles that rise from the ground, creating a folding form that breaks down street-level massing. A glazed entrance lobby creates a transparent and open connection to the street. The residential facility is a courtyard building with corridors facing inward toward a central green public space on the second floor.

The design’s folding forms and diagonal lines serve both aesthetic and functional purposes. They visually break down the massing of the building to integrate better with its urban environment and create dynamic interactions with natural light. This design likely enhances the building’s thermal performance by optimizing sunlight exposure, aiding in heating during the winter and reducing heat gain during the summer.

“Growing up in social housing in the Bronx gave me a unique perspective on the importance of community and high-quality, affordable housing. I took this insight to task when designing the Atrium at Sumner Houses; I wanted to create a place that felt like home to the residents,” says principal design architect Daniel Libeskind. “I hope this project is a powerful example of how good design can positively impact society, especially for those in need.”

Studio Libeskind collaborated with many partners to make this vision a reality while meeting the energy efficiency standards required by the NYCHA.

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A collaborative process

Studio Libeskind reviewed the details and challenges at the start of the project. Ultimately, it became clear an exterior insulation finishing system (EIFS) system with a limestone finish was the ideal choice, providing the project with a smooth, natural limestone look.

The EIFS included a drainage continuous insulation (c.i.) wall system that integrates an air and water-resistive barrier (AWRB), EPS insulation, and drainage. In other words, it has the five control planes needed to protect a building. The five layers of control are accomplished in an EIFS assembly as follows:

• Vapor control: Water vapour diffusion from areas of high to low vapor pressure must be controlled to minimize condensation within the wall assembly. Materials for each of the control layers in EIFS are specified as vapor-permeable or vapor-impermeable in accordance with recommendations from hygrothermal analysis of the exterior wall assembly.
• Air control: A fluid-applied membrane is the first layer applied in a typical EIFS assembly and must be tied into air control layers in adjacent assemblies to limit the uncontrolled airflow through the exterior wall, reducing condensation and energy loss.
• Water penetration control: The fluid-applied air control membrane in EIFS also serves as a barrier to liquid water and must be flashed to the exterior, designed and installed to prevent liquid water from entering the wall cavity. In a drainage EIFS system, vertical channels in the inboard surface of the insulation provide a reliable route for liquid water to drain to the exterior of the wall assembly.
• Thermal control: Since there is no external cladding and a metal support system is needed, EIFS provides continuous insulation with essentially no thermal bridging.
• Durable water-shedding: The outboard surface of EIFS is coated with functional finish surfaces connected to a resilient lamina to protect and divert water from the wall.

Challenges

On this unique facade, the perimeters of window penetrations are configured with angular profiles oriented to capture sunlight in the winter while allowing sunlight to cascade over the facade in the summer. As part of this dramatic design, the windowsills are set back into the facade. The setbacks could have made applying basecoats and finishes on the angled profile surfaces difficult. Fortunately, booms and hanging scaffolding helped crews access the hard-to-reach areas.

The integration of angled windows strategically manages sunlight exposure, minimizing heat gain during summer while allowing more natural light and heat during winter. This thoughtful placement contributes to the building’s overall energy efficiency and occupant comfort.

Some of the profiles’ flat, level surfaces could have led to water intrusion issues and costly repairs if not treated properly. The contractor met this challenge by using an acrylic-based, fiber-reinforced, flexible adhesive and waterproofing basecoat to build a water-resistant surface that sloped away from the building. This basecoat was applied to prepared concrete, masonry, plaster, gypsum, and cement sheathing surfaces at all windowsills and other horizontal surfaces. Once it had dried, a smooth finish was troweled on to achieve the appearance envisioned by the architect.

To prevent water intrusion, the team used an acrylic-based, fiber-reinforced adhesive and waterproofing basecoat to create sloped ledges that shed water effectively. Maintaining the continuity of all five control layers required precise detailing at transitions, including the use of compatible materials and integration techniques to ensure a robust envelope.

The finished project

Construction on the Atrium at Sumner finished in May 2024. The new building features 190 apartments—132 available to senior households earning below or equivalent to 50 percent of the Area Median Income (AMI), 57 reserved for seniors who had formerly experienced homelessness, and one designated for a live-in superintendent. NYCHA residents will be given preference for 33 of the apartments.

The project demonstrates how EIFS can effectively meet and exceed design performance goals, particularly under the stringent Passive House standards. By integrating continuous insulation, AWRBs, and a seamless, durable finish, the system provided a sustainable solution that enhanced energy efficiency, occupant comfort, and long-term durability.

Author

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Daniel Canova Sr. has worked in the construction industry for 40 years. His experience and employment has been focused on the exterior building envelope. Canova Sr. is a construction design manager and international design manager for Sto Corp. He is directly responsible for providing sales and technical support for Sto Corp. in all major cities and city centers in the United States. His specific responsibility includes sales and technical support focused on exterior insulated finish systems (EIFS), traditional cement stucco systems, pre-fabricated exterior wall systems, back ventilated rainscreen systems, fluid-applied air and moisture barrier systems, concrete restoration and exterior repair systems, products, and specialized material application equipment.

Key Takeaways

The Atrium at Sumner, an affordable senior housing project by the New York City Housing Authority (NYCHA), prioritizes energy efficiency with Passive House standards. Featuring high-performance exterior insulation and finish systems (EIFS), the building integrates an air—and water-resistant barrier, enhancing insulation and reducing energy use by up to 70 percent.

 

Source URL: https://www.constructionspecifier.com/atrium-sumner-eifs-building-enclosures/

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