crib boards are something sailboats have, usually 3 interlocking teak boards to make the vertical element of the main entry from the cockpit to belowdecks. A sliding hatch closes over them, makes the horizontal element and helps hold the crib boards in place and allows for a locking feature, usually a simple hasp and padlock.I thought this might make for a very unique entry but may be a huge pain in the butt to pull off. 
P.S. If I knew how to draw on this thing I would have drawn it up and made a much simpler and easier explanation
