e.g. PackRight Sport 1 Car Top Carrier, Pack Right Sport Rooftop Cargo Bag - Videos, Installations & Reviews We need more capacity for travelling to a campsite (bulky, light items like sleeping bags would be well suited on the roof). I already have a hitch installed and taken up with carrying bikes. I had intended on getting a rack and hard container but it seems a rack is around $250+ and a container is another $150-250, although bags can be had for as little as $50 and are well reviewed. The unique thing about the pack I exampled here (there are a few others) is that it doesn't even require a roof-rack, but I cannot locate anybody who's used one on a Prius. And yes, I really do need this capacity. Our last trip we had to use one of the three seats for stuff--car was jammed, and no I'm not buying a truck just to go camping a couple times/year
Yes, all such bags do that, whether with a rack or not. Their weight limit is generally 100lbs and we'd probably be doing much less, spread over most of the distance of the roof with bulky but fairly light items. I do see vehicles from time to time with roof bags but the hard shell containers are certainly more common (and much pricier). www.roofbag.com is another manufacturer, they claim to be the first to create this kind of product back in the 90's.
Have you got racks? If not how you gonna tie it down? If you do, why dont you mount a basket or pallet on the rack to take the load?
Think like a backpacker. There's gotta be stuff you don't use that can be left behind. Repack your food into individual, meal-size portions. Keep track of what you actually use and jettison the rest. Cut thr handles off your toothbrushes!
The bags aren't bad, but after a few uses, the lining inside starts to crack and fail (read leak) in wet conditions. I bought a used hardshell carrier fro $60 (Sears x-cargo) and use it on my wife's SUV, with the rack - it's much easier to use and pack. But, like you stated, it requires a rack.
I emailed roofbag about the non-rack method and whether it would impact side airbag and was told it would, not surprisingly.
They can, or alternately clips can be used, but they appear also to hook around the trim in a manner that would obstruct deployment.