With a manual awning the roller tube is held in place by the track, so there are no mounting bolts or screws at the top. Then because the arms can adjust to any length, the bottom mouning hardware can be attached all the way at the bottom of the wall and hit the bottom plate, plywood floor or even the aluminum floor joist. My point is during installation, it is not necessary for the arms to fall directly on two different studs.
A power awning has a track that must attach to the wall, but it is not the full height of the trailer, therefore it is better if it can be attached into a stud. Also the screws are located inboard from the top and bottom. While not an absolute requirement that it hits a stud, it is important that the track cannot flex (meaning it must be bolted tightly to the wall). And this is difficult to achieve with aluminum siding, the ribs of the siding would need to be flatten to achieve a firm mount. Or spacers/standoffs would be needed at each of the mounting points, again needing a solid stud behind.
Texas Baptist Men-Retiree Builders member since '01
13 Silverado 3500HD D/A, 2wd CCSB srw, custom RKI bed
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