Get a look under the bow platform wher you have access and see if it’s cored. It’s likely just glass but could have some plywood as a core. The other benches are probably built the same way. The benches are likely filled with flotation foam.What do you recommend as a repair technique to strengthen the top of these bench seats? They flex when I stand on them. They have no access, do you think they have foam in them? Should I install a large access hatch on the side and repair from the inside? Transom is solid and the hull is also solid. It's a 2008 15 ft Susquehanna Skiff that's been sitting for most of its life. The motor looks like it has less than 100 hours. I purchased it today from an older gentleman that never used it. I want to keep the same configuration, it works for me. I was also thinking what about just bonding a sheet of plywood coated in epoxy above the bench?