I understand it as well. I know the recommended space for my birds but typically make smaller coops with bigger runs. I've found mine actually benefit more from having a smaller sleeping area, especially in winter. Their body heat keeps them much warmer when they have less space to heat. The key is plenty of ventilation along the eves. In warmer weather the windows all stay open to help keep the space cool. Just because the "experts" reccommend something does not mean it is what is best for your particular flock.