LA MESA, C.A. (October 5, 2026) — Rainbow Investment Co. today announced that construction is underway on Cush Medical Plaza, a 52,600-square-foot Class A medical office development. Located adjacent to the Sharp Grossmont Hospital campus, Cush Medical Plaza will be a Class A medical office building within the Sharp Grossmont Hospital area in La Mesa, offering healthcare providers a rare opportunity to secure space in a premier facility designed exclusively for medical tenants.
The new two-story building is designed by Ware Malcomb, an award-winning international design firm. Ware Malcomb’s San Diego office is providing Architecture, Interior Design, and Civil Engineering services for the 52,600 SF project.
“Our family has deep roots in this community, and we are proud to deliver a project that brings world-class medical facilities to patients and providers right here at home,” added Stephen Cushman, President, Rainbow Investment Co.
Angela Ryan, Principal, Ware Malcomb, said the new building is part of a broader redevelopment of the lower Grossmont-area campus owned by Rainbow Investment Co. and the Cushman family. “This project provides Sharp Grossmont Hospital physicians room to grow their practices within walking distance of the hospital on the hill above the site,” she said. “The two-story configuration ensures the building remains efficient and highly leasable as medical office space.”
The building is designed using tilt-up concrete construction, a method more traditionally used for industrial projects that Ware Malcomb has been increasingly adopting in recent work. Public spaces feature significant glass and transparency, especially in the lobby, which represents an unusual and distinguishing approach for this construction method.
The building’s first floor will be marketed for flexible, multi-tenant medical office uses, while the upper floor is slated to become a new Sharp Family Residency Clinic, a combined family practice and physician residency training clinic serving both children and adults. The upper floor space design features a residency lounge, sleep rooms, showers, charting spaces, a training room, and fully functional exam and consult rooms for active patient care.
The team’s interior design for the Sharp clinical spaces follows the company’s established design brand, featuring soothing blues and greens, nature-inspired artwork, warm wood tones, watercolor-effect finishes, and generous natural light throughout. The intent is a soothing, inviting environment consistent across exam rooms, consult rooms, and shared areas.
Anchoring the project is a highly regarded tenant: Sharp HealthCare, which has committed to the full second floor. With this cornerstone tenant in place, approximately 25,000 square feet on the first floor remains available for lease, offering physicians and healthcare groups the opportunity to join a best-in-class environment that will set a new standard for medical facilities in East County. Demolition and grading are complete, the building permit has been issued, and vertical construction is underway. The developers are currently collaborating with prospective tenants on custom space designs to facilitate a smooth transition into build-out, targeting anticipated ground-floor shell delivery in mid-2027, with tenant improvements to follow.
Nehal Wadhwa and Matt Melendres of Cushman & Wakefield’s Healthcare Advisory team will be leading leasing efforts on behalf of the developer, Rainbow Investment Co. Leasing inquiries and additional property information are available through the Cushman & Wakefield property listing.
“Cush Medical Plaza is more than just a building; it’s a long-term investment in the health and vitality of La Mesa,” stated Wadhwa. “This is an exceptionally rare opportunity to deliver a Class A medical office building steps from the hospital campus, and we are incredibly excited to be a part of this landmark project for the community.”
Cush Medical Plaza offers a prime location adjacent to Sharp Grossmont Hospital, within walking distance of the hospital campus. The state-of-the-art Class A building features ample parking and flexible leasing options, with available suites ranging from 1,200 to 25,000 square feet. The project was designed by the acclaimed architecture firm Ware Malcomb and is being built by Turner Construction Company.
Turner is serving as general contractor for Cush Medical Plaza, working alongside Rainbow Investment Co., 12 Alpha, Ware Malcomb, and the project’s healthcare stakeholders to bring the new medical office development from preconstruction through construction. Turner was selected by Rainbow Investment Co. following a competitive general contractor interview process in which Ware Malcomb participated, with the selection reflecting Turner’s preconstruction rigor, extensive healthcare construction experience, and the cost certainty provided under a guaranteed maximum price contract. Turner’s role includes constructability and cost planning, procurement and trade partner coordination, schedule management, and field execution, with a focus on maintaining cost and schedule certainty while delivering the flexible infrastructure required to support both Sharp HealthCare’s clinical space and future medical tenants.
The property’s location in La Mesa offers excellent accessibility, with proximity to major highways such as Interstate 8 and CA 125, which see a combined traffic count of 228,000 ADT cars per day. The surrounding area is rich with amenities, including a variety of dining options like BJ’s Restaurant & Brewhouse and The Brigantine Restaurant, as well as retail stores like Trader Joe’s and Walmart. The nearby Grossmont Center provides additional shopping and entertainment options, making Cush Medical Plaza an ideal location for medical professionals and their patients.
Ware Malcomb’s Civil Engineering team led the grading, drainage, and utility design for the project. Luke Corsbie, Principal, said the overall site plan was designed to set up the campus for future buildings and future development phases beyond this first one. “The 8.95-acre site required a comprehensive plan for grading and utilities to accommodate the new building and future phases to maximize developable area on a steeply sloped, previously developed parcel within the Grossmont Center commercial district.”
To manage the significant grade transitions across the property, the site design incorporates seven retaining walls – totaling approximately 635 linear feet – that required its own permit process apart from the grading plans. Stormwater management is handled by two underground detention systems and three proprietary biofiltration units, providing both hydromodification control and water quality treatment.
The project’s utility scope includes new private sewer laterals, fire service laterals, and a main public water extension in coordination with the local water district under separate plans and permits. Public right-of-way improvements along both Center Drive and Grossmont Center Drive frontages include new curb and gutter, sidewalk, driveway modifications, storm drain infrastructure, and utility vault/pedestal adjustments.
General contracting services are being provided by Turner. Owner’s representation and project management services are provided by 12 Alpha, LLC.
A rendering of the project can be downloaded here.
About Rainbow Investment Co.
Rainbow Investment Co. is the real estate investment company of San Diego’s Cushman family, whose roots in the city date to the 1860s and who stand as the longest-tenured real estate investment family in San Diego. The family has owned and developed land in the La Mesa/Grossmont area for well over a century, beginning with approximately 120 acres of family farmland and dairy that evolved into today’s commercial and medical properties. Elliott Cushman, father of company President Stephen Cushman, developed Grossmont Center in La Mesa — San Diego’s first regional shopping center. Today the family spans seven generations of San Diegans, with the sixth generation now active in the family’s real estate business. Across generations, the family’s enterprises have ranged from automobile dealerships to shopping centers, alongside a deep legacy of civic and philanthropic leadership in the region, including its support of the Jacobs & Cushman San Diego Food Bank.
About Ware Malcomb (waremalcomb.com)
Established in 1972, Ware Malcomb is a dynamic, forward-thinking commercial real estate design firm providing professional architecture, interior design, civil engineering, branding, building measurement, structural engineering and MEP engineering services to clients throughout the world. With office locations throughout the United States, Canada, Mexico and Brazil, the firm specializes in the design of office, industrial, science & technology, healthcare, multifamily, retail, hospitality and public/institutional projects. The firm is also ranked among the top 10 Architecture/Engineering firms in Engineering News-Record’s Top 500 Design Firms and the Top 30 Interior Design Firms in Interior Design magazine’s Top 100 Giants. More than half of Fortune 500 companies are Ware Malcomb clients. For more information, visit waremalcomb.com.
About Turner Construction Company
Our vision is to be the highest value provider of construction services. We deliver our services on complex and challenging building projects of all types and sizes throughout North America and in 30 countries worldwide. We seek to create a healthy, prosperous, and sustainable future for our people, clients, partners, and the planet. We have earned a reputation for integrity, working safely, and driving innovation. With a focus on creating an environment where people can be at their best, be authentic, and be treated with respect and dignity, the company is widely recognized as a great place to work. The firm is a subsidiary of HOCHTIEF, an engineering-led global infrastructure solutions provider with leading positions in North America, Australia and Europe and a rapidly expanding presence in high-tech, energy transition and sustainable infrastructure markets. To learn more about Turner, visit www.turnerconstruction.com.
About Cushman & Wakefield
Cushman & Wakefield (NYSE: CWK) is a leading global commercial real estate services firm for property owners and occupiers with approximately 52,000 employees in nearly 400 offices and 60 countries. In 2024, the firm reported revenue of $9.4 billion across its core service lines of Services, Leasing, Capital markets, and Valuation and other. Built around the belief that Better never settles, the firm receives numerous industry and business accolades for its award-winning culture. For additional information, visit www.cushmanwakefield.com.
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Ware Malcomb San Diego
3911 Sorrento Valley Blvd. Suite 120
San Diego, CA 92121
858.638.7277
