I have made a drawing in floorplan with elevations. The elevationlines shows on this drawing. I copy the drawing to the layout. In the layout, the elevationlines has disappeared. The attached file illustrate this problem.
You did not post a screen shot of the floor plan, so I will guess that the lines you are referring to are the Marker Range lines, which are on screen only (do not print). You can check this by looking at View > On-Screen View Options > Marker Range.