Ventilation/circulation in brooder

[wholehearted]

I'm planning to use large Rubbermaid bins for brooding. Dh is making/modifying the top so that it will be fully screened. Do I need to cut holes in the sides for more air circulation or ventilation than what the open top provides? I've been looking at tons of brooder pics, and some seem to have open or partially open/screened sides while others just have the open top.

 

[fourleaffarm]

I'd say just the top open will be plenty. The more open your box is the harder it will be to keep heat in for the young birds, at least up here in NE.