Their advice sounds like it's more oriented towards more commercial set ups, (though they specifically labeled it "small scale poultry") where it's common to have a standardized approach to everything from amount of light to temperature regulation to type of feed.
Going by their assessment my...
While chickens may not love being in freezing temps a normal, healthy adult bird will not suffer from it either. The collective wisdom on this forum says most standard chickens do fine without heat as long as they have draft free, climate protected places to shelter (i.e. the coop, storm...