Ark coop building and ventilation questions

I started building my "ark" style coop using a rough sketch that had the approximate size and list of building materials that I found on a website. No instructions on building it tho so I am "winging" it. I am going to use hardware cloth on the top third of one side of the coop portion of the ark with clear plastic on the bottom 2/3rds for light. The coop area is 5.5' x 28" wide. I am planning on putting the roost lenghtwise down the middle.

My question is all the spaces around the sides and bottom where the wood doesn't meet. I thought I had built it incorrectly, or it is a design flaw since there is about a 3/4" gap where the wood is not flush with the frame due to the 1 x 3s used to anchor the sides and door flaps. I was going to cover the spaces up, but now I am wondering if they are for ventilation?

Any thoughts on this would be appreciated. I live in Huntington Beach, CA so we have pretty nice weather here most of the time. We get frost at night a few times in the winter and usually light ocean breezes in the afternoons. This is a side view of the coop so you can see the spaces that I am concerned about.

 

Thanks for the advise and encouragement. I've never built anything like this before so it has been an experience trying to figure it out and learning to use a skillsaw, jigsaw and miter saw! I am bracing the ends of the frames with the triangle pieces and using screws on everything instead of nails in case I ever decide to dismantle it to move.

I have 3 hens (I hope they are hens anyways) right now that are 4 weeks old. 1 Brown leghorn, 1 easter egger and 1 barred rock.

I will post pictures when it is finished, hopefully this weekend if it doesn't rain again.