I. C. Thomasson Associates Inc.: Gaillard Center

Existing building retrofit and addition of a multipurpose complex

By I.C. Thomasson Associates Inc. August 17, 2015

Engineering firm: I. C. Thomasson Associates Inc.
2015 MEP Giants rank: 46
Project: Gaillard Center
Address: Charleston, S.C., United States
Building type: Data center; Government building/military facility; Office building; Sports/entertainment/convention center facility
Project type: Existing building retrofit and addition
Engineering services: Automation, controls; Electrical, power; Fire, life safety; HVAC, mechanical; Lighting; Energy, sustainability; Plumbing, piping; information technology (IT)/security
Project timeline: 6/15/2010 to 8/15/2015
MEP/FP budget: $1,859,000


The Gaillard Center is a multipurpose municipal complex located in the historical district of Charleston. The building consists of an 1,800-seat, multipurpose auditorium, a 38,715-sq-ft exhibit hall, and a new three-story, 80,800-sq-ft municipal office building. The majority of the structure and the skin of the existing auditorium were left in place to preserve the history of the building. There are separate mechanical systems for each section of the building that were designed to optimize the different demand loads the building will see. The building is located in a high seismic zone and is susceptible to hurricane-strength winds and high-tide flooding issues that come along with being located in a coastal city. The mechanical, electrical, and plumbing systems were designed to withstand these criteria all while being integrated into a fine-tuned, state-of-the-art performance hall.

The city of Charleston’s municipal offices are located in the attached three-story municipal office building. Within the office space is a municipal emergency operations center (MEOC) designed to a Category IV level of construction, allowing it to be operational during and immediately following hurricanes and earthquakes. This portion of the building was designed with self-sustaining mechanical and electrical services. During a catastrophic event, Charleston’s essential government entities will operate from within the MEOC.

The Gaillard Center is scheduled to be a U.S. Green Building Council LEED-certified building and is the largest construction project ever undertaken by the city.


I. C. Thomasson Associates worked closely with design architect David M. Schwarz Architects, architect of record Earl Swensson Associates, and structural and acoustical engineers to make new mechanical and plumbing systems fit into existing floor-to-floor heights within the newly renovated auditorium. They also integrated those systems into architectural details and design of each space with little to no noise transmission.

The mechanical system for the new auditorium is designed to use demand ventilation and is equipped with carbon monoxide sensors to modulate outdoor air ventilation to maintain the space temperature while using the least amount of energy possible.

As previously mentioned, the mechanical systems for each area of the Gaillard Center are designed to be independent of each other to optimize the performance of the HVAC equipment and allow the flexibility needed to host a Sunday-afternoon matinee in the humid South Carolina summer while the municipal office space is shut down for the weekend.

The electrical system was designed to provide flexibility to serve both a state-of-the-art performing arts center as well as a municipal office building that included an emergency operations center. The performing arts center had very sensitive acoustic requirements. Due to the acoustical requirements, the step-down transformers that served all 120/208 V loads within the performing arts center had to be located outside of the building.

The emergency operations center has a dedicated electrical service with complete emergency backup generator, as well as a temporary generator connection point for additional backup if needed. The fuel system includes a tank located belowgrade sized to serve the emergency operations center for 96 hours without refueling at 100% load.

Lighting used a mixture of energy-efficient LED lighting and fluorescent fixtures. The fixtures provided an energy savings of more than 25% of the allowable lighting-power density of the 2012 International Energy Conservation Code. In the performing arts center, custom LED fixtures were used and were individually tested for acoustical performance.

Technology solutions for the structure were designed to provide flexibility and diversity in their networks and were constructed upon a Category 6 infrastructure. Multimode and single-mode fiber optic cable was delivered to each communications room from the server room to provide network connectivity to each space. The design provided for redundancy opportunities between closets as well. Each of the unique business demographics had to remain independent of each other for security reasons. Multiple wireless networks were developed to maintain that same separation.

The design of the technology solutions allows the MEOC to independently function aside from the rest of the building in the event of an emergency. Inside the MEOC space is the server room, which contains the head-end equipment for all of the network, communication, and security solutions necessary to operate a municipal government.

I. C. Thomasson Associates provided on-site construction administration services alongside Skanska USA/Trident Construction to oversee the installation of the mechanical, electrical, plumbing, and information technology systems.