Exactly what I have. Two large metal beams, each 30 feet long, one on the end of the building and one in the middle. The beam on the end of the building is supported by 3 metal posts. The one in the middle was sized to be a clear span. Metal floor "joists" with 3/4" T&G plywood flooring. Also had a beam installed in the ceiling of the loft, so that I could install a hoist to lift items up into the loft. I don't recall what the cost was, since it has been several years ago and was included in the build. I wanted it built so I could put some weight up in the loft, not just Christmas decorations and lights. Just yesterday, I put my small Kushlan cement mixer up there.