teamworker

3/4" plywood free span between angle iron mounted to side walls. When I got the plywood fresh and moist from Lowes, I cut the main piece the long way spanning and then set it in place with the better side down. I put on weights so it would dry deflected down. After dried, primed and painted I put it in with good side up now with a 1/4" crown. The brace for the foot board was made with bracing removed from the area under the floor. Head of the bed folded down for ease of loading groceries, etc. Full space for bins under bed. Foot of bed folds back to allow mid area fully open to carry dogs.

I used the beam across the middle and the angle iron at the back of the opening to make a brace to support the foot board of the bed, then added a piano hinge to the hatch door.

To access the area under the floor: