I'd use the foam. Some would argue that your roof needs to "breath"...but I don't think thats a big problem in a barn without a tightly enclosed attic and in a barn that will likely not be heated much. Without the foam "zig-zag" pieces you will certainly have many unwelcome visiters....birds, bees/wasps, and even a friendly squirrel or 2 (re: hundreds!).
So when do we get more photos so we know to keep beleiving your progress /forums/images/graemlins/grin.gif
Nice job so far. All your agonizing will pay off in a well made project.
went and picked up the foam seals from my metal supplier today, hoping to get the rest of the sheathing up this coming sunday..I dont have a digital camera, so i take pics with my regular camera as i go and when i use a roll, i have them developed and also get them put on a disk so i can post them on here.
UPDATE: We Finally poured some concrete today, we divided the building in half and did one half of it, it turned out absolutely great! Im very happy with the results, it was a little work but it payed off, glad we did it ourselves..