[Azzdodd]

It's not so much for them to get back in but to get out. Still not solved my eggs eating problem so there all now in a garden shed of an evening but I have to leave door open and magpies still eating away :/ so I'm thinking cat flap I can unlock when I go down off a morning and they will leave the house after they lay an hopefully magpies won't use it :/

[shygirl]

i have heard of hen house doors that open up electronically, i think its based on sunlight though, but maybe a timer.

[Azzdodd]

Yeah you can buy them there about £80 though

[Fleecewife]

Unless you can find a very light weight cat flap I think they would be too heavy.   Our hens stand outside our cat flap, peering into the kitchen and pecking to get in, but they can't open it themselves 
 
Also, if a hen could get in then so could a magpie - very intelligent birds

[sokel]

My sister has a cat flap and twice that we know of a jackdaw has got in through it
could have been going back out aswell because the cat food was vanishing very fast for quite a while

[Womble]

One of our black rocks has learned how to use the cat flap - we keep finding her in the porch eating the cat food!
 
I'm not sure it would work as a general rule though.

[shropshire_blue]

I thought you were going mad there, until I re-read the post title and saw it says cat flap, not flat cap!