I like them too,, but I would scale them down to 4 ft x 8 ft. they are quite heavy, and it is difficult to catch birds in them because they run to the opposite end.. you could reach them with a net if the distance was shorter,, now it takes 2 people to catch them,,
I have step by step pictures while I was building these..
the doors roll on overhead door rollers and track,, never plug up or freeze ..
I move these around with my tractor bucket and some special 4x4 forks that I made ..
are the pics in this forum or somewhere else...i was just thinking about the gathering of the birds...and to solve the issue i was going to build a temp gate that would go thru the center...for i need to build some of these units for the pheasants i will be growing out this year...seems like a good cost effective way to do this...not to mention portable...do the birds have hardware cloth for the bottom or a solid piece of something