They should always have feed available every hour they are awake,
and they will naturally fill their crops before going to roost as well as being healthier overall.
https://www.backyardchickens.com/articles/aarts-extreme-weather-spiel.75893/
That's a tough coop to ventilate without drafts, being so short.
Might help to see the inside of the coop showing the roosts and where the venting is.