We applied the effective liquid drop model to predict the alpha-decay, cluster emission and cold fission half-life values of nuclei in the region of superheavy elements (SHE). The present calculations have been made in the region of the ZN plane defined by 155 <= N <= 220 and 110 <= Z <= 135. Shell effects are included via the Q-value of the corresponding decay case. We report the results of a systematic calculation of the half-life for the three nuclear decay modes in a region of the ZN plane where superheavy elements are expected to be found. Results have shown that, among the decay modes investigated here, the alpha decay is the dominant one, i.e. the decay mode of smallest half-lives. Half-life predictions for alpha-decay, cluster emission and cold fission for the isotopic family of the most recent SHE detected of Z = 115 and for the isotopic family of the already consolidated SHE of Z = 111 are presented.