Ratio of dust ρ_d to gas (volume) density ρ_g as a function of radius r and height z, the latter in units of gas scale heights H_g (upper panels). Zoom-in on dust-to-gas density ratio ρ_d/ρ_g as a function of radius r and height z, with grid structure and dust particles being plotted as black lines and grey dots, respectively (lower panels). Simulations of the vertical shear instability only and of the scenario SIafterVSI with a dust size of 3 cm are depicted in the upper and left panel as well as lower and right panel, respectively. While the dust is stirred up to a marginally greater scale height with respect to the mid-plane in the former simulation, the dust layer is much thinner. Its width indeed amounts to less than a grid cell, while the layer in the latter simulation extends over multiple cells both in the radial and in the vertical dimension.