ABSTRACT
The ventilation system is a primary factor in keeping poultry cool during hot weather, but depending on the type of house other attributes contribute as well. For example, naturally ventilated poultry houses are typically oriented east-west to minimize the amount of direct sunlight entering the house. Direct sunlight on birds can create heat stress even if air temperature would not normally be an issue. The house roof overhang over the side wall will depend on the height of the side wall and the size of the curtain opening. More overhang is required as the side wall height and curtain opening increases. The design of roof will affect how much radiant heat is collected. Steep roof slopes of 45° will collect less radiant heat than a flat roof. Ideally, all roofs would be insulated in such
a way to minimize the heat collected. There are multiple methods of insulating roofs (dropped ceiling, polystyrene or polyurethane rigid board insulation, polyurethane foam and reflective insulation) but each has its advantages and disadvantages. The important aspect to remember is that the insulation needs to be done in a way that does not leave cracks or gaps for heat to transfer into the house. A dropped ceiling is popular in many countries creating an attic that can be insulated to prevent heat collected by the tin roof from entering the house into the bird environment. In houses that have tight construction to minimize air leakage these attics can be a source of warmer air during cooler months of the year as well as helping with brooding temperature during all seasons.
