We've been using hoop houses for birds for years now, the only problem we've had with them is they tend to blow over during the very high winds we get here in spring and fall. So we stake them down, and sometimes even tie them to trees! But I love 'em. They're easy for two people to move, and the birds kept in them on grass really thrive. I over winter pens of female bantams in them with no problems at all, if it gets really really cold I might staple some plastic on the front, but not too much as you don't want to trap too much humidity in there, as others have said!
See our hoops and tractors here:
http://www.pathfindersfarm.com/hoophouse.html
Cheers,
See our hoops and tractors here:
http://www.pathfindersfarm.com/hoophouse.html
Cheers,