Not sure if this has been said yet but, with the cost of lumber right now (at least in my area) and other parts and products, for just five hens you could get a small manufactured coop/run. Youd be able to move it around your yard.
Something like this or similar.
Best Choice Products 70in Mobile Fir Wood Chicken Coop Tractor Hen House Poultry Cage for 3-5 Hens, Outdoor, Animal Care w/ Wheels, 2 Doors, Nest Box, Removable Tray, UV Panel
https://a.co/d/2Vz4S1I
Easier to predator proof and you could drill extra insulation. If you have a shady spot you could put it, even better.
Sorry just thought I'd throw that in there!