Title: Crabtree Terrace Mixed Use
Location of Proejct: Raleigh, North Carolina
Project Completion Date: July 2020
Firm Name: Gensler

Short Description: The 186,000 square foot pedestrian-oriented office building, sited in suburban north Raleigh, integrates competing requirements of flood protection, connectivity, user experience, maximum rentable area and transparency to transform an abandoned floodplain site into a thriving retail and workspace environment that is a catalyst for future development in the area. At the heart of the development, a landscaped public plaza creates an intimately scaled amenity which fuses access to retail and offices uses while providing connectivity to the existing sidewalk network, greenway trail, bus stop and new on-site parking structure.

Architect's Statement: The 186,000 square foot pedestrian-oriented office building, sited in north Raleigh, integrates competing requirements of flood protection, connectivity to public space, inviting user experience, maximized rentable area and transparency. The project transforms an abandoned floodplain site into a thriving retail and workspace environment that is a catalyst for future development in the area.

Program
The client asked the design team to maximize leasable area on the 2.4 acre site while providing on-site parking. The project includes 145,000 sf Class A commercial office and 28,000 sf of retail space.

Context
Located in Raleigh, North Carolina across from Crabtree Valley Mall—the largest enclosed mall in the Triangle—and near the intersection of two major highways and the Raleigh Beltline (I-440), the site is in a sprawling suburban condition lacking design focused on pedestrian experience. The project overcomes immense design and budget parameters due to its location in the floodplain.

Access
The design promotes connectivity by linking the public sidewalk network, the existing bus stop and Raleigh’s thriving greenway system to a new elevated plaza. The plaza unifies the project and is an amenity to the office and retail tenants, a planned hotel to the west and the local community. Stretching between Glenwood Avenue and Creedmoor Road the site is highly accessible via automobile. A new 630-space precast concrete parking structure stretches north of the office building along a drive connecting both highways.

Plaza
At the heart of the development an internal plaza connects the retail spaces and offices uses to the existing sidewalk network, bus stop and new on-site parking structure while also being oriented towards a planned hotel development in the adjacent property. The plaza integrates architecture, landscape and civil engineering: The landscaped area doubles as a stormwater bioretention structure for the entire project site.

Main Lobby
The main lobby is an inviting entry space with a calm, modern aesthetic and signature light fixture. Full-height rift cut oak veneer panels frame commissioned paintings in the entry space, and mirror-backed acid etched glass panels define the elevator lobby.

Flood Protection
Due to flood elevations, the project addresses significant challenges relating to floor elevation, access, egress, foundation design, exterior wall design and opening protection while complying with zoning height limitations. While the most current FEMA flood maps indicate a base flood elevation about 4 feet above grade, the City of Raleigh had only adopted the prior version which indicates a base flood elevation approximately 10 feet above grade. Therefore, the project includes a custom flood-resistant curtain wall system up to 6 feet above the floor elevation in combination with flood gates at all ground floor door locations. Opaque assemblies include a fully waterproofed 12” thick cast-in-place concrete wall behind the cladding which varies between brick, fiber cement and aluminum panels.

Massing & Scale
The two-story portion of the building was conceived as a separate building to shape the plaza space and increase rentable area. Zoning limitations required it be connected to the main office floor plate; therefore, the components are joined with glazed connector at level 2. Set on a brick clad plinth, the two-story element is fully glazed along the plaza side while a fiber cement panel rainscreen defines the north edge and stair enclosure. The varied and smaller panels sizes, along with the matte finish of the fiber cement compliments the regular rhythm of reflective glass panels at the 6-story office volume.

Curtain Wall
Three curtain wall types define the context and experience of the building exterior. The upper levels (2-6) are characterized by two of these systems.

The curtain wall along the primary street edge wraps the corners at both intersections and is offset toward the streets from the adjacent curtain wall. This façade is highly textured by 9-inch V-shaped aluminum profiles and shallow offsetting horizontal mullions between. Experienced from the street, this façade enables the building to take on varying levels of transparency and opacity based on vantage point. Due to its predominantly south-facing orientation, reflective glass improves performance while allowing the façade to take on the colors of the surrounding environment.

The curtain wall at the north-facing plaza side of the building is restrained in contrast to the highly textured street facing façade. This two-sided structural silicone glazed system includes a single projected profile at the floor levels. The glass is less reflective and more transparent than the adjacent system.

At the ground plane, a 4-sided structural silicone glazed flood-resistant curtain wall system, with 1 13/16” insulated laminated glass, creates a minimal aesthetic that is highly transparent for the benefit of retail tenants.