I was wondering if anyone knew the maximum feasible length they could imagine a canoe on a my B5 saloon? It does have a Thule rack, im not some lunatic slapping a canoe on his bare roof
Most of the canoes that I want on Dallas CraigsList right now are around 17'... I think the A4 is about 14' in length.

 

I'm sure 17' will be fine. Just make sure u cover the holes on the canoes so it doesn't catch wind

 

then it sounds like 17' will fit, I would imagine whatever you want to put on the roof you can. I've seen an A4 with a Kayak on the roof, but I can't find the picture right now.