Is a standard brood box big enough-typically

[drex]

Last year I decided to run all double nationals, having started on single brood, then going to brood and half, which I really found a pain. I will continue on doubles, queens have done well at nearly filling both boxes. Makes it easier to swap boxes and frames around. Despite swapping over top and bottom boxes earlier this year, they have all still tried to swarm. The best has just had a fourth super added.