I moved into a 30 year old house this fall. The bedroom at the front of the house is colder then the others. Two sides of the room are brick exterior walls vs siding. I was in the attic running cable for a poe camera and noticed the brick wall. 

Not sure if this is the cause of the cold room but the top of the brick wall is exposed? From what I have read air gaps are required. I could not find anything referring if the air gap should be sealed?
[![enter image description here](https://i.stack.imgur.com/n3BuL.jpg)](https://i.stack.imgur.com/n3BuL.jpg)[![enter image description here](https://i.stack.imgur.com/OCzoz.jpg)](https://i.stack.imgur.com/OCzoz.jpg)