Hello @shaherwaheed61 and welcome to the forum..dont think i can come it much closer as already shared and explained here…so please create a new topic , share your dyn so far and a sample rvt…and an image with your graph zoomed in with all nodes expended so we can see what goin on, and tell which rvt version you are in as there have been some API changes for how get ceiling grids…since this post was created… so the forum can take a look and try help you…cheers