I am trying the Joel Salatin method of using light temporary structures for everything nowadays. We have two enclosures suitable for turkeys:
1. Six feet of wire fencing surrounded by shrubbery, with about 140 square feet of shelter in the barn and, oh, gosh, the run is about 30 x 90 feet. Barn's ex-manure pit has been swept out and is open to the run. All I have to do is build new gates for the wire fencing, and put in some roosts, the existing ones are crummy.
2. A large-ish ex-manger, about 60 square feet, attached to the side of the orchard. Orchard is fenced with 6' stockade, and is 70 x 80 feet.
And then I'm in the process of building a sort of moveable hoop house tractor. I want to put some sort of foraging- and scratching-type poultry in the hoop house in fall, to eat the weeds and fertilize in the garden beds before I mulch 'em in November, and then use it as a sort of cold frame in spring to start the veggie seedlings. This can also be used as a handy transit method to run bunches of flighty poultry between housing, especially between the barn's "poultry hospital room" (a separate room in the front of the barn that is heated in winter) and the regular housing.
I would make the pen out of something stronger/heavier than PVC pipe. You don't want it blowing away in a strong wind. And I say that from sad experience...
