The present disclosure relates to methods and apparatuses for generating a through-silicon via (TSV) model for RC extraction that accurately models an interposer substrate comprising one or more TSVs. In some embodiments, a method is performed by generating an interposer wafer model having a sub-circuit that models a TSV. The sub-circuit can compensate for limitations in resistive and capacitive extraction of traditional TSV models performed by EDA tools. In some embodiments, the sub-circuit is coupled to a floating common node of the model. The floating common node enables the interposer wafer model to take into consideration capacitive coupling within the interposer. The improved interposer wafer model enables accurate RC extraction of an interposer with one or more TSVs, thereby providing for an interposer wafer model that is consistent between GDS and APR flows.