Broadband communications for indoor powerline networks with impulsive noise using Orthogonal Frequency Division Multiplexing (OFDM) is considered. From earlier investigations, it is known that this channel suffers from multipath fading and frequency selectivity along with manmade impulsive bursty noise. Nevertheless, the calculated channel capacity limit promises very high data rates over this channel. In this paper the bit error rate (BER) performance of the OFDM system under impulsive noise and frequency fading is theoretically analyzed and closed form formulas for this performance is derived. Furthermore, a theoretical upper bound on the performance of coded OFDM system is obtained, given perfect interleaving and the effect of the interleaver length on coding performance is also studied.