Shower cubicle on roof rack?

[Stanios]

I've got quite a small van in transit connect with two roof rack bars and a shower enclosure comprising of 3 boxes that when laid onto the rack come out about half a foot on each bar (total box length about foot longer than distance between roof bars).
Is it safe to tie it up with rope to rack and drive around like that?

 

[SimonG]

Aye fine. I have a doblo and any thing that doesn't fit gets strapped to the roof bars.