Buddy in AK, I would rule out plastic because of your location..... If you want a simple do-it-yourself system, use schedule L or K copper pipe. It's easy to assemble and it's lighter than black pipe. I doubt that you are designing an elaborate system with lot's of outlets, so it's your choice on which material to use. It may be the cost that is the deciding factor and black pipe may be the way to go. I did some research and found a few articles/sites that may be of interest to you. I like the Garage Pak System. however I do not know the cost, availability or durability of the system. Maybe Ken Brown will jump in, I believe that this is his field of expertise. grin ....g

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