welll. too much ventilation in Fairbanks might kill chickens..... (-40F and colder)This is just straight pink fiberglass (which doesn't mould). We put up vapour barrier then plywood. The insulation goes into the eaves except for the 2 (Count it.TWO) holes that I was allowed to put in for ventilation. ONE article was read about someone who said they put in too much ventilation and all of their chickens died. If you ask me they probably had too many drafts, but because of that one stupid article I'm not allowed to properly ventilated. If my girls don't end up with severe frostbite this winter I will be amazed. Next spring I'm going to climb up on the roof and just cut the ridge off, raise it and create a ridge ventilation. Either that or I'll build a new bloody coop my way.
but most other places aren't that crazy cold. .. making a tight coop usually results in all kinds of respiratory illness. ... and yeah frostbite too with the higher humidity.