Building a coop in Ireland means you're not just outsmarting foxes, you're also negotiating with the sky. The original poster is planning for free-range chickens, peahens, possibly guinea fowl or geese, and they're asking about materials, requirements, and predator-proofing in a climate that's wet, rarely freezing, and occasionally warm enough to make you forget you live on an island famous for rain. That's a lot of variables, but it's also the kind of project that separates a casual chicken keeper from someone who truly respects the fowl.
Our honest take? Stop thinking about the coop as a house and start thinking about it as a fortress with ventilation. In Ireland, your main threats are foxes (who will dig under anything that isn't buried deep), mustelids (stoats and pine martens that squeeze through gaps the size of your thumb), and birds of prey that treat open runs like a buffet. That means your floor needs to be either solid concrete or buried hardware cloth at least two feet deep, no shortcuts. Use treated timber for the frame, marine-grade plywood for the walls, and corrugated metal for the roof to shed that relentless rain. And please, for the love of all things cluck-tastic, skip the chicken wire. It keeps chickens in, but it does nothing against a determined fox. Use welded wire mesh with half-inch openings, and reinforce every seam with screws, not staples.
As for the mixed flock, peahens, guinea fowl, and geese, they're not all going to fit in the same coop without a fight. Peahens need height; they roost high and wide. Guinea fowl are basically flighty, noisy escape artists that prefer to sleep in trees if you let them. Geese are ground-nesters and need a separate, low-roofed shelter. Trying to combine them in one coop is asking for fowl play of the worst kind. You'd be better off building one main coop for the chickens and peahens (with high perches and a covered run) and a second, simpler shelter for the geese. Let the guinea fowl free-range during the day and lock them in with the chickens at night, they'll adapt, albeit loudly.
Here's the practical takeaway: your coop doesn't need to be pretty. It needs to be dry, ventilated, and predator-proof to the point of paranoia. Use pressure-treated lumber, galvanized hardware cloth, and a roof that doesn't leak. Bury the wire. Add a lock that a raccoon, or a clever fox, can't slide open. And if you're keeping peahens, give them a perch at least six feet off the ground. Build it right once, and you'll spend more time watching your feathered friends than patching holes. Build it wrong, and you'll be feeding the foxes a very expensive dinner.