This 640,000-sq-ft, 25-story office building is on one of three parcels of the four-acre Fifth & Mission (5M) development in the South of Market District. 415 Natoma includes two levels of below-grade parking, multiple ground-level retail spaces, and exterior amenity decks. What’s more, the building would rise around an occupied 110-year-old apartment building.

The two-year construction effort required careful orchestration of site logistics due to the concurrent construction of a new residential tower and public park. With a nearly 50,000-sq-ft first-floor plate and fronting an entire city block on four sides, arranging deliveries, concrete pours, and staging was a near-constant task.

The limited space prompted innovative solutions such as running concrete slickline beneath an adjacent street to a small laydown yard where the concrete pump was placed. This allowed concrete trucks to offload with minimal street closures. Close coordination with city traffic authorities allowed traffic lanes on one street to be restriped to provide space for loading and offloading trucks. The project team also successfully coordinated a 100-ft electrical vault installation beneath the sidewalk and adjacent traffic lane.

Photo courtesy Swinerton

The team overcame supply chain challenges through careful scheduling and coordinating the most efficient delivery method for each type of material. Rather than routing all materials to the Port of Oakland some were sent to the Port of Los Angeles and transported to the Bay Area. Construction was completed on time and on budget in November 2021.

The innovative buckling-restrained brace system eliminates a concrete core, allowing elevators to be located on the north exterior side. This system leaves the entire south face completely unobstructed, taking advantage of the solar exposure, especially in the winter. The varying geometry with multiple terraces, three curtainwall types and two primary storefront materials create a dynamic appearance.

With wellness and sustainability in mind, 415 Natoma achieved triple certification – LEED Gold, WELL Health and Safety and Fitwell Community. The spacious lobby has three panels of innovative bypass sliding glass doors that open the entire corner to the outside to allow plenty of fresh air, no columns for unobstructed views, and minimal sightlines. A plumbing greywater system reclaims sanitary waste from sinks, showers, and rainwater for reuse in water closets, urinals, and irrigation. This project also has multiple outdoor terraces on the upper floors for tenants to enjoy.

Photo courtesy Brookfield Properties

In response to the coronavirus pandemic, 415 Natoma’s designers and engineers quickly strategized how to make this building safer for the occupants. The team implemented several safety features, including upgrading air handlers and elevator recirculating fans to MERV 14 UV filtration, touchless door entries and dispensers for soap and paper towels, and updating the elevator ventilation system with air ionizers. A dedicated outside air system provides tempered, dehumidified air to the building’s core and shell. This allows tenant improvement upgrades to use sensible cooling of the various floors, saving energy and eliminating conventional condensate drains.