In electrophoretic deposition, a voltage difference is applied across a suspension, and a layer (cast or coating) is formed on one of the electrodes. Based on first principles, cast growth is described in this work for a well-stirred suspension, a constant voltage difference across the deposition cell, and a nonionic solution. The influence of cast formation on cast growth is implemented, which is a refinement of the model described in 1999 by Biesheuvel and Verweij. Simulation results are compared with experimental data. From the derivation it follows that a smooth cast layer is formed when the particle permittivity is lower than that of the liquid. Catastrophic cast growth occurs when the particle permittivity is higher than that of the liquid.