Bridge for Halloween yard haunt, spider webs all around it. Build a solid structure with no give in the walkway. then cover with 1" foam from the local fabric store. Cover the foam cushion with your catwalk slats...
We built a walk thru coffin door entrance to our first haunt structure. I ran out of time (as we home haunters always do!) before I figured out how to attach the door in such a way that we could open it on hinges. But even still, people we visited were impressed with this Halloween prop....A piano hinge would work well here....eb
50 Best DIY Halloween Outdoor Decorations for 2016
For a light-weight version, use foam board from Home Depot or Lowes, and shape with a serrated knife and wood-burning tools. (Make sure your room is well ventilated when using wood-burning tools with foam!!)