10 steps for controlling house moisture
Ag engineer Michael Czarick suggests 10 steps for keeping poultry house litter dry.
Question: How do I keep my litter dry without spending a fortune on propane?
Answer: Keeping litter dry is all about prevention. The fact is that if you wait until your litter begins to cake to start increasing your timer fan settings, it is too late. It took days or weeks of under ventilating for the moisture to build up to the point where cake begins to form, so bumping up a timer 15 or 30 seconds is not going to make up for days or weeks of neglect. The truth is that once litter becomes damp it typically takes a dramatic increase in your timer fan settings (i.e. double or triple) to have significant effect on litter moisture. The problem, of course, is that dramatic increases in timer settings tend to lead to dramatic increases in fuel usage.
Here are 10 steps that can be taken to keep excessive litter moisture from becoming an expensive problem during cold weather:
Controlling litter moisture starts the day after the previous flock goes out. Make sure to cake out the house as soon as possible. Not only does this get rid of some of the moisture in the litter it tends to aerate the litter a little and that aids the drying process.
Try to keep the house as warm as possible between flocks. Though it would be nice from a moisture removal process to keep a house in the 90s between flocks, it simply is not practical. What is practical though is closing a house up tight at night (running a timer fan or two a minimal amount). Then during the day, if it is relatively warm outside, turn on some fans or drop the house's curtains to help remove moisture from the litter. Yes, a little electricity is going to be used but it is cheaper than using propane to dry the litter once the chicks are in the house.
Run circulation fans between flocks. A little air movement across the litter goes a long way to help remove moisture from the litter.
Work on getting your houses tighter. You have probably noticed that litter caking often occurs in those cooler areas where air leakage is a problem (sidewalls, end walls, tunnel curtains). This is because cool air does a poor job of removing moisture from the litter. Ventilation is not just bringing in fresh air; it is about bringing in fresh air and heating it before it moves down to bird level so that it can remove moisture from the litter.
Ventilate a little when you are preheating a house. When you heat a house you draw out a significant amount of moisture from the litter. By operating a timer fan or two, you can exhaust moisture from the house, which allows more moisture to be pulled from the litter. This is especially true in houses with fresh litter.
Manage the drinker system properly. If drinker height is too low or the water pressure is too high, excess moisture will be added to the litter, which will have to be removed through ventilation. Make sure the drinker lines are clean, by flushing on a regular basis. Debris in the water lines can result in leaky drinkers.
Use circulation fans throughout the flock. Circulation fans help to remove moisture from the litter in two ways. First they move the hot, dry air from the ceiling down to floor level where it is needed. Second, they gently move air across the litter surface, which significantly increases the rate at which moisture is removed from the litter.
Use house relative humidity to determine if you are ventilating sufficiently. The ideal Rh is somewhere between 50 percent and 60 percent. If the relative humidity is 70 percent or greater first thing in the morning, your minimum ventilation setting is probably too low and should be increased.
Increase timer settings during the day to take advantage of the fact that daytime temperatures are typically 20 F warmer than nighttime temperatures and relative humidity of the air outside the house is typically half that of what it is at night. Think of the litter in your house as a bank. The more moisture you can withdraw during the day the less you have to withdraw at night when outside temperatures are low.
Don't increase timer settings only 10 or 20 seconds. Get ahead of the game. If you are going to make an increase to your timer fan settings, make it at least a 30-second change.
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