I used 10 ft. pieces 0f ½” grey electrical conduit mounted on a base made of treated 2x4s, then covered the frame with galvanized corrugated roofing tin. I used plywood for the front and back. The whole thing is held down by a couple of mobile home tie-downs and can be lifted off the pump if need be. It has worked out well, and, thanks to the magic of Kool Seal (or actually of less expensive products similar to Kool Seal), still serves its purpose today.
I didn’t get out much back then, and I actually thought a PVC Quonset was an original idea. Since then, of course, I’ve seen many a Quonset made pretty much the same way.
It always seemed like PVC pipe and roofing tin would make for a simpler, cheaper, more interesting shed than wood, siding, shingles, and the like. But the problem with making a PVC Quonset bigger than a pump house, at least for me, was the pressure that bigger pipes put on those puny plastic couplings when you bent them enough to form a Quonset. Those couplings were prone to cracking. I once tried using a heat gun on the pipe to help it curve and take some pressure off the couplings, but I didn’t really have much luck.
I’ve seen some twenty foot lengths of 1” to 1.5” inch pipe here and there, but wasn’t sure how I’d get that stuff home without a delivery charge
adding to the cost of my shed.
The answer to these little dilemmas came from this web
site: (http://www.wps.com/J/BM/PVC-Quonset-Hut-assembly/). I’d never thought of using 12” lengths of larger pipe as couplings. True to that writer’s word, pressure alone is enough to hold the 10’ lengths of 1” pipe together when using those 12” pieces of 1.5” as couplings.
The Burning Man shelter featured on that website was temporary. I’m hoping mine will be a permanent storage facility. Instead of using rebar uprights to hold the pipe at the base, I made the base of PVC pipe held together by plastic tees, and buried it in approx. 6” deep trenches, which I hope will hold the hut better to the ground. Also the end pieces include uprights (in the back, one treated 2x4 and in the front, two 3x4” landscaping timbers) that are cemented like posts in the ground.
My Quonset is approximately 10’ by 10’ at the base. I was lucky to have scrap sheet metal from the mobile home we disassembled and other sources, and a few sticks of treated 1x4 laying about.