Ours are all Schedule 40, 1 inch. I have seen up to 1.5 inch schedule 40 pipe used. Schedule 20 will not work, to flimsy.

With that said, to help support a snow load, I put up a 2 by 4 "Beam" down the center, with two posts to hold it up. Then in the winter I add one more "Beam" on each side of the center beam to help carry the snow load. The side ones can be taken down, but I have left them up as it was too much of a hassle to remove, store and put back up.

We have had as much as 14 inches of snow on our PVC tunnels with the wood beams. We did remove the snow in the morning.

Jay

i don't think you can bend sched 80 without heating it first.

Ok, jr you used 3 foot spacing between hoops as I remember. Is that max?