Elevating Student Housing Above People’s Park

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The Judith E. Heumann House is University of California Berkeley’s new high-rise student residential building located adjacent to the campus, on the historic People’s Park site. The 12-story, 328,000 square-foot dormitory will address the urgent need for housing by providing over 1,100 new beds for undergraduates. The project had to address a number of unique considerations and overcome extraordinary challenges during the planning, design, and construction of the project. These included navigating through an extensive planning and environmental review process, overcoming legal challenges, integrating the new building with the established neighborhood and residential community, honoring the important historic legacy of the site itself, and providing supportive housing for the unhoused population living in the park.

The response to these challenges shaped the design of the project to inform the program, unit layouts, massing, and overall scale of the building. Several alternatives were explored during the conceptual design phase to develop optimized apartment-style units that would deliver the highest bed count with the lowest overall cost. The resulting design balanced these considerations with an unusual solution: a pair of independent structures, combined functionally into a single building, each designed with a specific purpose and strategy.

The structural design was tightly integrated with programmatic needs of the project and emphasized economy, efficiency, speed of construction, durability, seismic resilience, and sustainability. One of the unusual structural challenges was elevating one of the structures 30-feet above grade to allow pedestrians and the open outdoor space to flow freely under the building.

The Judith E. Heumann House will welcome its first class of incoming students in the Fall of 2027. This will be one of the university’s largest residential developments and has a complicated and storied history. Development plans began in 1967 when the university bought the site through eminent domain, demolished the existing buildings, and planned to build dormitories. The project did not materialize due to a lack of funding. Over the following 50 years, the site became a gathering place and symbol of political action and protest, earning itself the title of People’s Park. In 2018, the university revived plans for student housing at the site and spent over five years on extensive planning, design, public engagement, rigorous environmental review, and legal efforts to realize the project.

Protests and lawsuits against development on the historic site held up the construction for three years. Ultimately, the California Supreme Court ruled that the University could proceed with the development. The project broke ground in January 2024, after the site was fenced off and secured with double-stacked shipping containers around the entire perimeter.

Once completed, the development will create urgently needed student housing to support growth in enrollment and address the chronic shortage of housing for undergraduates. UC Berkeley houses less than a quarter of its undergraduate students—the lowest proportion in the UC system. In addition to the new student beds, the project will preserve and revitalize more than 60% of the site as public park space, and create permanent commemorations of the site’s history. The separate permanent supportive and affordable housing building, to be developed and operated by a non-profit partner, will provide approximately 100 units and on-site services for residents.

Heumann House is one building divided into two wings—each a separate structure. The north wing features 11 stories of student apartments over a ground floor and a partial basement level and reaches a height of 154 feet. The south wing is elevated 30 feet above grade to allow the park space to flow across the site. This wing has six stories comprised entirely of student apartments with an average height of 95 feet.

The location of the two wings and the site plan were organized to maximize the quality of the open space. A variety of building massing concepts were explored during the initial design to optimize building footprint, height, and configuration of open space. The T-shaped footprint emerged as the most appropriate to address the University’s goals; the largest portion of the development is along the northern edge of the site with a slender tower and small footprint, and a smaller portion at the south wing juts into the center of the site.

The T-shaped organization of the student housing massing design minimizes shadows on the park and the nearby historic buildings. The placement of the larger northern mass along Haste Street preserves the entire southern edge of the site for maximum daylight exposure. The east-west orientation of the northern wing is optimal for solar control of the apartments and reduces heat gain.

The structures are carefully sited in response to the neighboring buildings and the street grid. By aligning with Hillegass Avenue, the south wing visually resolves a dead-end street and creates two landscaped courts within the 1.5-acre park. The eastern court is bounded by Dwight Way, Bowditch Street, and Hillegass. Smaller and more intimate, the court is surrounded by institutional and religious buildings, First Church of Christ Scientist by Bernard Maybeck and the Julia’s Morgan’s Berkeley School of Theology building. These two historically important buildings form the edges of this new open space and provide the necessary light and air to mitigate the change in scale. The massing of the buildings drops in scale from north to south, from the larger institutional buildings on the north side to the more residential structures to the south.

At the heart of the site plan is the 1.5-acre park. From above, it might appear as two open spaces, one located to the east and one to the west, but from the ground level they are connected. The foundational design response was to elevate the south wing, which was brought up more than 30 feet above the ground to allow for the open space to flow uninterrupted under the building. This wing is supported on a specially designed long-span transfer structure that allows a landscaped passage below. Columns are removed and transfer beams put in place to maximize the open space and connection between the eastern and western open spaces. The passageway through the south wing is enhanced with a custom-lit acrylic ceiling. The dimmable light system provides a dramatic highlight to the space below the south wing.

To address cost and construction efficiency, the design of the structures relied on simplicity and repetition to capture the benefits of scale. The structure uses simple forms, flat surfaces, and minimal complexity to maximize construction productivity.

Type I concrete construction with post-tensioned slabs was determined to be the most appropriate structural system for the buildings. The structural design solution was tightly integrated with the layout of units and circulation corridors. This led to an efficient and symmetric column layout and span arrangement that resulted in slender and efficient floor assemblies. The typical floor plate has an elongated rectangular footprint roughly 62 feet wide and 326 feet long at the north wing and 177 feet long at the south. The columns are arranged around the regular unit module to provide an efficient span layout and minimize the thickness of the slab assembly. The resulting two-way slab is 7 inches thick, spanning a maximum bay size of 22 feet by 28 feet, with edges cantilevering more than 5 feet. This approach did not require drop caps or additional beams simplifying formwork and creating clean soffits.

Detailed finite element models of the slabs allowed for optimization and strategic load balancing of the post-tensioning tendons to minimize deflections. This ensured a reliably flat floor structure and stiff slab edges to support the cladding panels with minimal vertical movement. The analytical studies considered deflections from both short-term loading and long-term creep.

A key consideration for the design of the slabs was punching shear resistance. The goal was to minimize stress from gravity loading and provide punching shear reinforcement for additional strength and ductility under seismic movement. Standard “studrail” reinforcement was included at each slab-column connection and at the ends of the concrete walls. Ordinarily, punching shear reinforcement is not provided at wall ends because stresses under gravity loading alone tend to be low. However, a detailed assessment of seismic behavior revealed that punching shear stresses under seismic loading are elevated significantly locally since the slab-wall joint is subjected to inelastic rotations from both lateral drift and the uplifting end of concrete walls.

The structures use a Special Reinforced Concrete Shear Wall system for seismic resistance, per ASCE 7-22. The minimalist three-sided arrangement of planar shear walls is neatly integrated into corridor and unit demising walls. The arrangement mirrors the unit module to provide efficiency, redundancy, and torsional resistance with a limited footprint to minimally impact the program spaces. The shear walls are arranged such that they are continuous through the height of the building, without openings or disruptions.

Both structures are supported on a deep foundation system that uses a total of 433 24-inch diameter auger-cast friction piles extending down to a maximum length of 76 feet. The piles were designed to achieve an ultimate strength of approximately 800 kips in compression and 430 kips in tension to resist seismic loads.

Much of the concrete structure was exposed and incorporated into the aesthetic design of the building. Recognizing the large potential environmental impact of concrete construction, the team specified low embodied carbon mix designs that replaced up to 50% of portland cement. This resulted in a 35% to 40% reduction in the overall embodied carbon of the structure. The concrete mixes were tailored for each application. Higher cement replacement was targeted for foundations, walls, and columns, where rapid strength gain was not critical. Post-tensioned slabs had less cement replacement to accelerate cure time for stressing.

While the overall structural design strategy emphasized simplicity, efficiency, and economy, its implementation relied on a performance-based approach for enhanced safety, reliability, and resilience.

The structure was designed to conform with the 2019 California Building Code and the University of California’s Seismic Safety Policy. The Policy provides guidelines for “assessing buildings based on the latest advancements in scientific understanding of seismic events, as well as for associated changes in California buildings code arising from advances in engineering methodologies.” This Policy requires an independent third-party seismic peer review and, for Berkeley, also involves review by the campus Seismic Review Committee. This results in a thorough vetting of the analysis and design procedures and allows for a more sophisticated performance-based approach. In this context, the engineering team took advantage of the nonlinear response history analysis (NLRHA) procedures, per Chapter 16 of ASCE 7-22, to provide a more accurate and reliable basis for seismic design.

The analysis was carried out using the CSI Perform 3D program. The earthquake demands were established based on a campus-specific risk-targeted acceleration response spectrum for the maximum considered earthquake (MCER). The hazard spectrum assumes Site Class D, with short-period and long-period spectral acceleration values of SS = 2.276g and S1 = 0.878g, respectively, resulting in a Seismic Design Category E designation. A suite of 11recorded ground motions, scaled to the MCER hazard spectrum, was selected and used for the design of the lateral force resisting system. The scaled records contained fault normal and fault parallel components which were rotated to align with the axis of the model relative to the nearby Hayward fault. The structure was assigned to Risk Category II and designed to meet a Seismic Performance Level of III, per the UC Seismic Policy.

While the initial configuration and proportioning of the concrete walls was determined with simple methods using equivalent static lateral forces, an explicit performance evaluation considering inelastic response of the structure and foundations allowed for tailoring and design optimization for improved reliability, resilience, and efficiency. Eliminating openings in shear walls minimizes discontinuities, providing a more effective load path and more efficient design. The shear walls in each direction are proportioned to have the same thickness and length throughout, creating a repetitive and simple layout allowing reuse of forms and increased productivity over the height of the building. They are also laid out to eliminate the need for openings, minimizing disruption and simplifying reinforcement details. This regular, repetitive approach streamlined the construction process and improved cost efficiency.

A specific hierarchy of failure modes was established to ensure that inelastic actions were controlled and localized in specific elements detailed for ductility and toughness. For these deformation-controlled elements, inelastic seismic demands were carefully tracked to ensure they remained within acceptable material strain limits. Protected force-controlled actions and elements that have limited or no inelastic deformation demands, were checked for strength.
The primary concrete shear walls were proportioned for flexural response. In addition, they were capacity-designed to limit shear stresses and compressive strains to eliminate brittle failure modes and prevent excessive damage. Computed mean values for transient interstory drifts at the MCER level were limited to 2.7% for the north wing and 2.5% for the south wing. These are well below the maximum values of 3.8% and 4.0%, for the north and south wings respectively, allowed in ASCE 7-22. Computed mean values for residual inter-story drifts were limited to 0.28%. Though there is no explicit limitation on residual drift, a value below 0.3% typically indicates minimal permanent geometric distortion and that cladding joints, elevator shafts, and other critical elements that rely on vertical alignment would remain intact. The low values of transient and residual drift signify a meaningful improvement in the resilience of the structure.
The North and South Wings are functionally connected by a bridge that is integral with the South Wing. The Wings are structurally separated by 27 inches at the bridge connection to allow for maximum anticipated movement and eliminate pounding between the buildings.

To further demonstrate the reliability and redundancy of the design, sensitivity analyses and defect scenarios were conducted to test modeling parameters and bound the results. Due to the inherent uncertainties in characterizing soil and material properties, upper and lower bound values were used to evaluate structural response and test the sensitivity of modeling assumptions. This was required by the third-party review as a way to ensure key uncertainties were addressed in design. To test the structure for unanticipated construction defects, the structure was analyzed under several hypothetical conditions representing potential deviations from the design. These include simulated brittle boundary zones at plastic hinge locations representing premature fracture of confining reinforcement in the shear walls and loss of post-tensioning strands in critical prestressed elements under lateral loads.

The importance of the building and its criticality for meeting the housing needs of the students drew heightened attention to the post-earthquake condition of the building. From a performance standpoint, the seismic design focused on providing a measure of resilience. In addition to addressing basic strength and serviceability requirements, the system was designed to reduce drift and minimize potential damage to reduce the potential downtime and cost of repairs following a strong earthquake.

Though a resilient structural design is of primary importance and the first line of defense against intense ground shaking, a great deal of attention was paid to the anchorage and detailing of critical non-structural systems such as cladding elements, stairs, elevators, plumbing (fire sprinklers, water, and wastewater lines) and electrical equipment. A combination of measures was taken to provide adequate allowance for movement or increased bracing forces to prevent incidental damage that would hinder re-occupancy of the building. The idea is to make it easier to shelter-in-place, reoccupy, and keep the building on-line after an earthquake, even if repairs are needed to make the building fully functional. In certain cases, higher Fp forces were used for water supply and emergency power. In these cases, the new and expanded ASCE 7-22 code provisions for non-structural components were used instead of the active code of ASCE 7-16 in the 2019 CBC.

The central expression of the integrated architectural and structural design solution is the elevated transfer structure that supports the south residential wing above the park, allowing the open space below to continue seamlessly across the site. Simply carrying the closely spaced building columns to the ground would have created a forest of exposed pillars, interfering with pedestrian circulation.

The transfer structure in this context would be massive, visible, and costly. The urgency of developing an effective and appropriate approach made it the focal point for the client and design team. Several alternative design strategies for the transfer structure were explored to balance architectural expression, seismic performance, constructability, and cost. Potential strategies included a rooftop transfer structure with hanging floors, tree-like branching structures supporting the floors above, and transfer-girder solutions with different column configurations. Ultimately, based on extensive input from the University’s Architectural Design and Seismic Review Committees, a post-tensioned concrete transfer girder structure was selected as the most appropriate and reliable design solution.

This unusual approach borrows construction techniques that are more commonly used for large bridges. The 5-foot-deep transfer structure at the third level uses a two-way arrangement that relies on a series of single-span girders in the transverse direction and a pair of continuous multi-span girders in the longitudinal direction to eliminate 10 of the 26 columns that support the structure above. The entire structure essentially rests on six pairs of architecturally shaped monumental concrete columns that are over 25 feet tall and measure 5 feet 6 inches by 3 feet in plan. The transverse and longitudinal girders are reinforced with mild steel and high-strength multi-strand post-tensioning tendons to provide sufficient strength and limit deflections.

The design of the transfer structure posed significant challenges and unique considerations, particularly for seismic loads. For gravity loading, it was critical to control and minimize short- and long-term deflections to ensure that the long-span girders would remain effectively flat and level. Post-tensioning was a key to accomplishing this goal. By introducing a permanent counteractive prestressing force that balances the column point loads, instantaneous and long-term creep deflections were effectively reduced to negligible levels. Without the post-tensioning, this would have required significantly deeper girders to accomplish.

The tendons were installed in flexible ducts that were cast into the girders and left ungrouted. The tendons typically consist of 36-strand bundles, with 0.6-inch-diameter epoxy-coated strands, each delivering about 1,500 kips of prestressing force. Each of the girders incorporates two or three tendon bundles, with harped profiles which efficiently resist the imposed point loads. The unbonded tendons are anchored at the girder ends with specialized hardware that allows for simultaneous stressing of the entire bundle of strands. The longest tendons were about 122 feet in length and were stressed from one end.

It was doubly critical to ensure that the transfer structure would be protected from earthquake actions and always retain its integrity to support the structure above. Due to the inherent stiffness of the massive girders and columns, the transfer structure participates in resisting seismic loads; acting like a moment frame that interacts with the primary shear walls.

The basic strategy was to increase the strength of the shear walls below the third level to limit inelastic response in the components below and keep the structure essentially elastic. The additional strength was achieved by thickening and combining the planar shear walls into a core section below the third level. While the design allowed minor localized yielding, the drift was limited to ensure that critical elements such as the post-tensioning tendons and girder-column joints, would remain damage free under all cases considered. This consideration partially drove the decision to leave the tendons ungrouted and to provide epoxy-coated strands for corrosion protection. This makes the tendons less sensitive to lateral movements and limits the seismic strain demands on the tendons, making them less susceptible to fracture.

Special attention was paid to the detailing and constructability of the transfer structure. The heavily reinforced girders were carefully detailed to ensure that the intersecting tendon profiles, anchor hardware, and rebar would be coordinated and installed with appropriate tolerances. Full-scale mock-ups were built to test the constructability of congested zones such as the girder-column joints.

Construction sequencing and temporary shoring were major considerations for the design of the transfer girders. To balance the load of the structure above and control deflections, the post-tensioning tendons were left unstressed until the roof structure was completed. This represented the full self-weight of the structure prior to the addition of superimposed dead loads from cladding, interior construction, and mechanical equipment. The girders were shored with large pipe columns that were left in place until after the girders were stressed and loads transferred. Additional piles were provided to support the heavily loaded temporary shoring columns. Once the stressing was complete, the transfer structure could support the weight of the building above and the shoring posts were removed.

The Judith E. Heumann House represents a sophisticated integration of architectural vision and structural engineering, successfully transforming a site with a complex and storied history into a vital, high-density residential community for UC Berkeley students. By addressing significant seismic and site-specific challenges, most notably through the implementation of a high-performance, long-span transfer structure that elevates the south wing to preserve open space, the project balances urban densification with cultural and community sensitivity. Ultimately, the integration of performance-based seismic design, efficient concrete systems, and sustainable construction practices ensures that the building will meet the urgent need for student housing and serve as a resilient, functional landmark for years to come. ■

Leo Panian, SE, is a Principal with Tipping and served as the Structural Engineer of Record for the project.

Gregg Novicoff, AIA, is a Principal at Leddy Maytum Stacy Architects and along with Richard Stacy and Marsha Maytum served as Architect of Record for the project.