Prior to performing handoffs for indoor services, a mobile station (MS) needs to scan for an accessible femtocell in hierarchical cellular networks. The longer scanning time denotes the higher power consumption for the femtocell and gives an extra burden to the MS as well. Using adaptive thresholds with a margin for received signal strength indicator (RSSI) of adjacent macrocells, we propose a new scanning scheme to minimize unnecessary scanning procedures for an accessible femtocell. Also, it is shown that the proposed scheme outperforms a conventional scheme through analysis and simulations. The proposed scheme can be a reasonable solution to lessen power usage and processing burdens in scanning procedures.