I have had 2 pole barns that were my shop and I now have an all metal building and am wondering if I made the right choice. I have a 30 x 30 with metal c channel for beams going across the 30ft. span. The perlins were closer together on my pole barns and the roof seemed stronger when you walked on it. I now feel like I am walking across a mobile home roof. I don't see any give when it is walked across but just feels different. Is this c channel stronger than 2 x4's that are closer together.