How big do I need to make my brooder? how tall should I make the sides? I am getting five ducklings. 4 girls and 1 boy. I have 4 chickens about two years old in my run and coop. I plan on getting some type of fencing and fencing off a part of my run so they can get used to each other (I will start dong this when my ducks are older between 3-4 weeks or when they don't need the heat lamp). I will keep them out there in the run for a few hours each day then bring them back into the brooder to sleep. I will do this until they are big enough to hold there own with my chickens. my chickens are not mean but you know how chickens are with smaller birds. So I need a brooder that will be big enough. Do ducks ever jump over the sides of the brooder if they are not tall sides? my chickens did. so I had to place peaces of wood across the top with spaces in between. What do you think?