I have a bunch of friends who like to tease me about my Prius. One of the most common complaints they have, and most unjustified, is that there is no room. Well lately I have been doing some fabrication and needed steel. I've had to drive my truck in to work since the only good steel yard is 40 miles away, but on the way home from work. NOT good on the gas budget. This last friday I stopped in at a welding supply shop a friend said was starting to carry steel. Their prices were not good, but cheaper than another trip to Escondido. So I figured what the heck and checked to see if I could fit a 10' piece of 1.5" tubing inside. Wish I had known, I wouldn't have had to have the other steel yard cut up the 1'X2" tubing. And I could. Fit quite well from the back to the dash. I am a bit worried about the potential of busting the windshield, but with a large towel I should be OK. My work commute in the Prius is like $6, in the truck it's like $35, and I really can only get a 10' piece in the bed of the truck anyway. That'll save me a ton to pick up small orders of steel in my Prius, and this one is really fun to show my friends who just don't get the Prius, especially the ones in the off-road community.
Hey I didn't think you'd have any trouble carrying steel in a Prius, I have no problems getting wood in mine. (sick pun intended) , Seriously though, just last weekend I had to pick up a few 3.3 meter (over 10') pine posts and I was sure they wouldn't fit in the Prius. I thought I'd end up paying an extra $30 to have them delivered but what do you know they fit in there just nicely.. Saved me some cash. Same deal as in your case, I just wrapped the ends pretty thoroughly with beach towels to make sure there was no damage. BTW. Here's some nice pictures of another member getting wood in his Prius. http://priuschat.com/forums/gen-ii-prius-main-forum/87514-pix-1-face-cord-firewood-in-prius.html
I have built an entire deck using 10ft redwood, all material carried in the Prius. The only things I have not been able to fit in there when I tried: 4x8 sheet of whatever (drywall, plywood, cement board, etc...) A couch and loveseat Everything else has been a success. Including a giant 30W CO2 Laser, almost 1000sq ft of 12x12x3/4" italian slate tile, a drywall hanging machine, Dewalt chop saw on a large base and stand, and the list goes on. And the couch/loveseat had to ride in a Chevy (Silverado maybe?) but neither fit in the bed, they hung off the end.
I regularly carry up to 20 8' t-posts or 6 8'x4" wooden posts for fencing or restoration work. Those fit without having to put them on the dash and they are too heavy to do that anyway. People just don't expect you to have so much room in the Prius.
With that kind of a difference in commuting cost, soon the materials will be free! I'd still be concerned with the steel going through the window. Sure, it fits, but in an accident you could be putting yourself at risk. If there's some way you can secure the load with straps and tie-downs, using the hooks already in the car, that would be safer. I've carried long loads both ways: up on the dash, and sticking out the back. I have a device that hooks on the latch to hold the hatch mostly closed while under way, and I keep the driver's side window open to ensure a supply of fresh air. It really is amazing what fits. I picked up a three-drawer lateral filing cabinet the other day. It had to be coaxed over the bumps, but otherwise slid right in. The two-wheel dolly fit in, too.
^Cool!^ There is another thread about Prii hauling stuff around, here it is. http://priuschat.com/forums/showthread.php?t=90008 There is a member that had made a support rack to haul lumber maybe you could make something like that for your metal stock? I had ordered 4, 55 pound suitcase weighs for my tractor 220 lbs total. When I went to the dealer to pick them up they were very surprised and a little skeptical I was loading them in to my Prius. I use my Prius when I can to deliver produce verses using my van or wife's truck. Aloha, ED
Be careful you don't spear yourself if the load shifts and you hit someone. Or someone hits you in the back. Yikes.
The biggest single thing I had inside was a small love seat. I had to remove the cover in the trunk area to drop it low enough to close the hatch but that was all. I think if I had that steel beam I'd try to put it with the front end in the passenger foot well.. if you remove the passenger front seat head rest and slide the seat all the way forward you can recline it level with the back seat... then you may be able to put that beam in a position that is more friendly to sudden stops... and clumsy loaders. It may not fit that way, or you may need to drop the lower glove compartment, but if you're going to be doing this a lot then I'd try it.