Securing storage boxes to roof rack...?

Good morning all

​​​​As per the title, just wondered what the general consensus is, please? 
​​​​​​I'm planning on buying some sturdy plastic storage boxes for the roof rack (maybe Peli cases or similar); I know I could throw a ratchet strap or ropes over, but is there a neater solution, that's perhaps more secure, less likely to result in boxes being nabbed and possibly even semi-permanent?

Thanks all - again!

You need to consider that the max. load on the roof is, from memory, 35 kg and that includes the rack. There have been discussions on this problem before and a number of members believed that a better option is a trailer. It is certainly worth thinking about.

Roger

Thanks Roger, I'll certainly be considering a trailer for larger loads (and the dump etc.); I was thinking more about a box or two on the roof for things like welly boots, wet weather clobber and such like - nothing overly heavy.

Small U bolts through the bottom of the box and under a spar on the rack same as is used on the big rooftop boxes you get from the likes of thule etc.

Bicycle inner tubes. I use them to strap on snowboards and surfboards. They don't smack your face like bungee cords do. But there are tubes with different finish. Some can cause black smudges on the items you are fastening, but other tubes have a more glossy surface and it's them you want. The rubber deteriorates by UV light though, so they can't be used as permanent solution.