Pancake ice, the circular floes formed during ice growth in a wave field, forms in many polar and subpolar seas. Vertical thin sections of cores taken from the ice cover in these regions show distinct layering structure. These observations suggest wave rafting could play a significant role in defining the ice cover thickness, much more so than thermodynamic growth. Although wave rafting is intuitively apparent, no previous study relating the resulting ice cover to wave characteristics has been conducted. In this study we utilize both laboratory experiments and numerical simulations to determine the rafting process. We propose a theory that predicts a final equilibrium thickness, provided that the incoming wave is kept constant. The equilibrium thickness from the theory is proportional to the square of the wave amplitude and the square of the floe diameter and is inversely proportional to the cube of the wavelength. This theory relates the final ice cover thickness to the wave characteristics and the size and surface properties of the pancake ice floes. This theory also provides a way to calculate the speed with which the boundary between the single-layer pancake ice floes and the equilibrium rafted ice cover propagates. We conduct laboratory experiments with plastic model pancake ice to create rafting. We perform computer simulations with a three-dimensional discrete element model that simulates the movement of disc-shaped floes in the wave field. We compare the theoretical result with the laboratory experiments and a numerically simulated rafting process. Both the laboratory and the computer simulation results compare favorably with the theory.