I guess if it is used strictly for looks, you could get away with it. I would think it would have little to no functionality though.... Just my 2 cents

 

A big problem with PVC is that it is brittle and will shatter/break. If you used Schedule 80 PVC pipe, it might work. Schedule 80 = thick wall and stronger. Schedule 40 = "typical", thinner wall and weaker.

Steel is ductile and will bend, not break. That's a good characteristic to have when you have a loaded roof rack and hit a big bump in the trail. I could see the PVC roof rack breaking.

I'd also be worried about UV degradation of the PVC, although painting it would probably take care of that concern.

 

I made a door frame from PVC and it just wasn't strong enough I would be hesitant to put any we eight on it

 

NO! :nonono::nonono: Needs to be metal!

 

Not only is function an issue, i feel like it wouldnt have a good look. By that i mean, to make nice rounded corners. The easiest option is to use elbows. But the are fatter then the tube that they connect.

At the same time, i encourage you to try, and put some pics up and possibly go from there.

Maybe the whole thing doesnt have to be made out of it? IDK the answer! But try it and see what happens