depends on the canoe, an old Grumman aluminium canoe could perhaps take  being on its side, but never a cedar canvas or stripper. I'd even be loathe to do it to a plastic canoe :)
You have to consider the forces applied by the lashing straps, and the dynamic things that go on when driving fast or over bumpy roads.
Kayaks are a different kettle of fish, river kayaks are ok on the side.

alistair

On 2012-08-19, at 7:17 PM, Harry Hoffman wrote:

> Hi All,
> 
> So, I finally have managed to aquire some thule roof racks for the van.
> 
> Does anyone know if you can carry a canoe on its side when travelling?
> 
> I'd like to be able to carry a canoe and some other stuff but I have a
> feeling if the canoe was flat I'd have no room for anything else.
> 
> Anyone carrying one on its side?
> 
> Cheers,
> Harry