: Any hollow, air-filled structure needs venting if you're going to
: prevent pressure differentials caused by changes in temperature.
: That's why people vent the bulkheads in their kayaks.

I can vouch for that!!! I didn't have holes in my bulkheads and was finding that when I put the boat in the cold water while the air temps were warm, it would suck air in around the bad seal I had on my hatch coaming!!! Of course, if you had any water sitting around the rim, it , too, would get sucked in. And I was wondering why my hatches were leaking!!!

Sean