Thanks for your time. I am sorry for confusing the questions. The Vinyl Siding Contractor says the piece that is rotting is the Rim Joist underneath the sliding glass door that sits on a 2x6 (not a 2x4). The 2x6 sits on top of the basement foundation wall. He also has said that the Jack stud is not directly above the floor joist; therefore, the rotted Rim Joist should be replaced. We worked out a deal with the Vinyl Siding Company that they would replace any Rotted wood. No one was aware of the Rim Joist being rotted at the time. By contract, should the Vinyl Contractor be responsible for replacing this? Thanks again. I will check out your references.