Do you ever have problem that some of your grids are missing on floor plans? In this example, I can see all of my grids on floor plans for level 1 to 5. But for level 6 or above, the grids are missing.
If you see all of your grids are missing, it could be you turn off the grid visibility in Visibility/Graphics Overrides. The other possibility is you hide the grids in certain views.
But if you find none of those are true, then you need to check the grid lines on elevation view.
Check if your grid lines extend beyond the level you want it to show. In the example below, the grid lines are only slightly above level 5. That’s why I can see it on level 6 and above.
To fix it, all you need to do is select the grid. Then drag the grip at grid’s end until it extents the top most level.
Now you should be able to see it on every level.
Why this happens?
This could happen if you add more levels after you created the grids. The grid lines will not automatically extend their length to the new level.
That is why is most Revit books, it is recommended to set levels before you draw the grids.