Wood rot in the walls, ceiling and floor of used older camper is very possible, it all depends on how the prior owner took care of and stored the camper. You can inspect for water damage with a moisture meter, and suggest you do so before buying to know what you are getting into before hand. I'm not saying not to buy a camper with a low level of damage, just know going into the deal better educated to make a decision you can fix yourself or live with it. This link can help show how to get one and use it. https://www.sunlineclub.com/forums/f...per-17613.html
Sunline did make a few aluminum wall studs and floor joists travel trailers, they were limited though. I do not know of any Sunline 5th wheels made with aluminum wall studs etc.
After dealing with many water infected campers, both aluminum wall studs and floors and all wood studded campers on several brands, the materials the studs and joists where made from is not the issue. The leak that went on a long time never discovered was the issue.
Hope this helps,
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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