Frequency regulation (FR) is the electric grid service responsible for maintaining the system frequency at its nominal value of 60 Hz in the United States an indicator of energy balance on the grid. In cases of mismatch between power supply and demand, FR resources either on the generation or the demand side, responding rapidly to restore system frequency to its nominal value. Due to the limited responsiveness of generators, fast and accurate demand side resources (DSR) have recently been encouraged to participate in FR. However, the tested DSRs typically require high initial equipment investment (e.g., flywheels and batteries). Large commercial buildings can provide effective load shaping with little impact to occupants' comfort and have significant amount of available capacity for FR participation. In addition, commercial buildings are characterized by numerous interdependent HVAC subsystems and control systems. Therefore, a high-level supervisory control strategy is needed that directs the interdependent HVAC systems for FR with strengthened interactions and depressed counteractions. Simulation results suggest that large commercial buildings can provide significant FR capacity and high performance scores. Dynamic building-to-grid integration automatically and continuously provides solutions maintaining energy balance on the gird. The benefit to the power system reliability would be significant. (C) 2014 Elsevier B.V. All rights reserved.