: The air pressure needs to be able to flow both ways. Before I had a hole in
: my bulkhead, I once opened my hatches (held with bungie cords) on a hot
: afternoon then paddled on very cold water. The air beneath the hatch
: contracted so much that it took two of us pulling as hard as we could,
: just to get the hatch cover off. I've never seen it happen, but have heard
: stories of decks collapsing as the air inside cools and contracts.

: John

That's good information John and I see how that could happen. What I am thinking now is to drill a 1/32" hole and put a small piece of canvas over it. The canvas on folding buckets will leak until they become water soaked and the weave expands and they they become water tight. So it looks like air would pass through the canvas equalizing the pressure until it became soaked with water and then it would stop the water from intering the compartment.

John