The trailer does have a solid I-beam frame running the full length of the trailer, albeit under the plastic covering. There is a small aluminum tack strip, you can unscrew this, and the plastic will come out so you can mark it where the frame is. Note that some Rockwood trailers have a 3/4" wood plank attached to the frame, which will have some give to it. WHen I attached my steadyfast, I cut the plastic trim around the frame mounts. You def. want to be sure you mark the frame, so your support doesnt go through the covering