This is my brooder made out of a dog kennel and boxes. The boxes are over a foot high. I know the bars might be a little wide for newborn chicks so I added the boxes. My question is will they be able to jump the boxes and get through the bars or will they be big enough to not fit through by the time they are able to jump that high?
you might want to put translucent vinyl(we did great with cut-off clear plastic bag, fixed to all cage corners with small clithpins). The alternative would be caging them in someplace with a roof so low that they will not be able to jump at all(which is a bit cruel imao). Be careful also with heating lamps if you are using one in the brooder. Some quail chicks are set on killing themselves with the thing(e.g. falling asleep under too intense a heat that they almost get cooked, sticking their bodies into the narrow gap between heatlamp/feeder/waterer/wall/roof, etc.) Preferably remove, replace, or wrap any object that can cause them harm.