I tried that - I even put the cutting plane up 30 metres and it still was slicing off - ie. I had this problem but it wasn't a view cutting plane issue.
So... If anyone read through all this and didn't find the answer, then here's what worked for me - I needed to go into the Design -> Story Settings dialog, and change the "Height to next" value for my topmost level from zero to something logical (ie. that included the height of the whole roof)
