I Wncreasing sidewall height doesn’t significantly increase heating costs
hile there’s a common misconception that poultry houses with higher ceilings have much higher heating costs than those with lower ones, this simply isn’t true. Rather, heating costs have much more to do with insulation and ventilation.
For a modern, totally enclosed broiler house, raising the height of the sidewall from two and a half metres to three metres will result in heating costs rising by less than 5%. This is because even though a 20% increase in sidewall height increases heat loss through the sidewalls by 20%, the sidewalls represent a very small percentage (6%) of the total heat loss from a poultry house. So, increasing the relatively small amount of heat loss through the sidewalls by 20% or even more would not have a big impact on the total heating cost. By far the biggest source of heat loss is ventilation, accounting for around 70% of the total cost of heating a totally enclosed poultry house; increasing sidewall height would have no effect on the amount of fresh air birds require.
This isn’t to say that higher ceilings can’t be result
in higher heating costs. In open ceiling houses - houses without attic spaces - it tends to cost 10% or more to heat than dropped ceiling houses, not because the ceiling is higher but rather because the insulation value is a half to a third that of a dropped ceiling house.
Greater surface area
An open ceiling house also tends to have a greater surface area than a dropped ceiling house. Gaps between insulation boards and at the peak of the house tend to make an open ceiling house looser, further increasing heat loss from the ceiling. But in a dropped ceiling house, if the sidewall height is increased, the ceiling doesn’t change and so heat loss through the ceiling remains the same. The only factor contributing to higher heating costs is extra heat loss through sidewalls, which is minimal.
There are several advantages of higher ceilings during cold weather. Coverage area of radiant heaters increases as ceiling height increases. When a radiant heater like a tube or a brooder is installed at a relatively low height, floor temperatures will tend
to decrease rapidly as you move away from a brooder. This reduces the number of chicks in a house that receive some measure of radiant heat. Conversely, when installed high above the floor, coverage area is increased and floor temperatures tend to decrease more slowly as you move away from the brooder or tube heater. In wider houses, it can be a challenge to install radiant heaters at an optimal height. The relatively low mounting height significantly reduces coverage of tube radiant heaters, and can lead to fairly high floor temperatures directly under the tube heaters. Having a higher sidewall in this situation could help to improve floor conditions across the width of a wide house.
It is also important to realise that as ceiling height decreases, bringing in fresh air during cold weather without chilling the birds becomes more difficult. During cold weather, the air space above the birds is used essentially as a mixing chamber. Warm air produced by a house’s heating system and the birds themselves rises and collects near the ceiling. Cold air→