Building a successful homemade poultry egg incubator depends on several factors, including being able to maintain a steady, warm temperature, regular air circulation (this can be provided by cutting small air holes in the container), and keeping the incubator humid with a wet sponge or small water dish. The material for the incubator can range from a 30-gallon Styrofoam cooler, to plywood, to a discarded refrigerator; the main heat source is typically a 25-watt lightbulb. You may wish to limit your investment in incubator materials until you know how long you intend to hatch poultry eggs.
Incubator Container
If you are trying to build the incubator as inexpensively as possible, you may want to use an nearly airtight container you already own. If you don't have something at least as large as a 30-gallon Styrofoam cooler, you may wish to purchase one, pierce a few small air holes in it, then cut a hole large enough to insert a light bulb extension through. Make sure it is easy to open and close because you will be opening it to turn the eggs at least once daily. If it is not flat already, flatten the bottom of the container so the eggs do not roll.
Heat Source
Incubator designers recommend light bulbs as the heat source. Use as many light bulbs as it takes to maintain a temperature of 101.5 degrees Fahrenheit in a still air incubator; if your incubator has a fan (forced air incubator), aim for 99.5 degrees.
Monitor Temperature
You may already have a thermostat handy, but if not, make sure to purchase one that goes as low as the ideal temperature you need for your incubator. Thermostats are typically available at hardware stores. A fan inside your incubator can help to keep the temperature steady but is not a requirement.
Maintain Humidity
Poultry eggs need humid air to stay alive, so add a small water dish or a wet sponge that you dip into water when it begins to dry out to your incubator's floor. Some incubator designers recommend monitoring the humidity with a hygrometer; relative humidity should measure 50 to 55 percent for chickens.
Test Run
To ensure your electrical setup will not accidentally harm the eggs you intend to hatch, let it run for several days to make sure it stays at a steady temperature. Consider hatching only a few eggs on your first run-through.
