Does my house need a gable vent?

Quote from the video:
Quote from Youtube video: That don't quite understand it or other contractors. Say oh you'll be fine you got gable vents you'll be fine just not understanding how that convection of that cool air coming in and moving straight

How do you tell if my roof is vented?

How to determine whether you need better attic ventilation

  1. Look at your eaves and roof. …
  2. Touch your ceiling on a warm, sunny day. …
  3. Thick ridges of ice on your eaves in winter are a sign of poor attic ventilation. …
  4. Warm air that escapes living space also carries moisture that will condense on rafters or roof sheathing.