Having lived through the repair of slide floor rot....
My opinion which is based on the fall out of my prior owner or the dealers lot, if you are using the camper, slide being out is not a problem.
If you lock up the camper for days/weeks on end, bring it in. The slide seals, and every thing else slide related will last longer under cover retracted in the camper. I would not leave it open in the winter in snow and freezing temps unless I was using it.
I know folks at full time CG's leave them out during the week when they are home, but that does not make it a good thing. If they use the camper 60 days a year or even more, then the slide is exposed to the weather the other 300 days not in use.
I never thought about this much until I had slide floor rot...
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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