Mesh size to contain new chicks

[Catkins500]

Hi, I'm new to the forum and wanted to ask what size mesh would safely keep new chicks inside the run? I've a broody hen and she's now sitting on eight fertile eggs that I got for her as she's so desperate to hatch a brood. I was advised by the experienced breeder I got the eggs from to separate her and her chicks from the other two girls once the eggs hatch. I've a six by two meter run with a coop inside. I was going to partition off one third for mum and chicks until they can all rejoin the other two hens. I've got a nest box for mum and chicks and some fine gauge netting to divide run but it occurred to me, will the chicks be able to get through the 25mm chicken wire of the run? I don't want them to end up outside the run with mum unable to get them back inside. Should I run some of the fine gauge netting round the bottom of the run on the other three sides of the partitioned area? Any advice welcome!

 

[FlyWheel]

newly hatched chicks have a way of getting through some ridiculously small holes, I certainly wouldn't go any larger than 2cm square, smaller would be even better. 1cm would be the best bet, as then none of them will get their heads stuck once the start feathering out, and it will prevent the larger birds from pecking at them through it also. Especially if you intend to raise them in the same coop with the bigger birds.

 

[Catkins500]

Thank you for the advice FlyWheel. I was thinking of using butterfly netting or something similar, pegged down so the chicks can't push under it. I'll definitely put it round the other three sides in that case, as well as using it for the partition.