Leakage power has become an important component of the total power consumption in FPGAs as process technology shrinks. In addition, a significant amount of leakage power in FPGAs is consumed by the routing resources. Therefore, leakage power reduction in FPGAs should begin with the routing resources. In this paper, we propose a novel directional coarse-grained power gating architecture for switch boxes. In addition, the existing VPR routing algorithm has been adapted with a new cost function to support the new power gating architecture. Results have shown that the new cost function yields an average improvement of 22% as compared to the existing VPR cost function in terms of the number of power gating regions that can be turned off.