In all recent technologies the delay caused by interconnection wires is essential in the evaluation of the switching speed of integrated structures. Completely wrong results, would result if this were neglected. By considering a distributed RC network to model the interconnection lines, we proposed a new analytical delay time expression for a general tree type network, with full incorporation of technology design parameters. A computationally simple technique is presented and comparisons with HSPICE simulation results show the accuracy of the developed model in timing verification.