I'm sorry, but that is only adequate for one hen. Each hen needs 4 square feet. What is the weather like where you are? Will it get cold this winter? Will it get wet and snow? That is nowhere adequate for 13 hens sleeping on top of that all winter. What protection do they have from predators?the coop is about 1 x 4 feet. very small, but most of them sleep on the top of the coop regardless.