I wrote Jayco about this very question last Fall. I am 350#
I also asked about what appeared to be stretched roof membrane in that there is a bubble of material that runs the length on one side. I don't know how else to describe it.
This is the response.
Jayco doesn’t have a weight rating for the roof, therefore we advise the customers to use caution when accessing the roof and if need be use a sheet of plywood to spread the weight of an individual on the roof. It is common to have extra or what appears to be extra roof material on the edges with an occasional bubble or wrinkle. We suggest the customers typically this is nothing to be concerned about though should keep an eye on the wrinkle or bubble.
Lucky for me, My wife has volunteered to go up on the roof. I am just too afraid of going through the roof, even with a piece of plywood.
Wayne, Kim, Mallory & Abby the Dog
2013 - Jayco Jayfeather - X20E
2012 - Toyota Tacoma DBLCB Sr5 with towing package
Equalizer 10k WD, Prodigy P3 Controller, TST TPMS
2012 - Jayco Sport 10 Popup - Traded