I originally had hoped that I would not have to clip my chickens wings but after numerous attempts to stop them flying over the fence I gave in and clipped them. My fence is 4 feet high and a couple of the chickens did fly over for the first 2-3 weeks but eventually this got less and less except for just one of them which got in the habit of flying over pretty much every day. As installing a taller fence would have been costly and not really practical clipping the chickens wings was the only answer.
How about nailing them to the perch….. but seriously, do other people fully enclose the run, ie add a roof mesh?
As I understand it if you have a 6 foot fence the chickens are less likely to get over it. As the area I gave to my chickens was quite large it would have been quite expensive to have added a mesh roof to the entire run although if it had been smaller i probably would have.