This often indicates either not enough coop space and/or ventilation.They try every night to sleep on top of the coop or in the pine tree but I always put them back inside for their own safety
What are the dimensions of your coop?
Ditto both those, and a tape measure will tell the whole tale.A picture is worth a thousand words...
Oh, and, your climate/location would add more info.
Sorry for all the questions, but with limited info, it's hard to give viable solutions.
The pic you attached shows a very narrow space...but there may be more to the coop than is shown there.