2008 Jayco 71c. I, and others, have posted on other threads approaches to soft floor problems. One thread is "New Hybrid . .. soft floor .. is this normal?".
Based on my experience I tell people to avoid sandwich construction flooring campers of any model. If they own one and it is ok, sell or trade it.
Water is can be a problem. Another is flexing, at first very little, at pressure points like just inside the door and in front of the sink. The flexing became a discussion for us in 2014 and makes the camper unusable in 2015. Ours deteriorated quickly.
The compromises of making a 3,500 lb gross weigh camper at a $15,000 price point ($12,000 actual) for our camper meant inadequate tires and flooring material.
Go to other threads like "New Hybrid . .. soft floor .. is this normal?" to read what is being tried.
I'm with you on this, I've been there and done that. I also tell tell people to avoid sandwich construction flooring, they are nothing but junk in my book.
2015 Jay Flight 23 RB
2014 Silverado LT 1500 with a 5.3 V8 Ecotec3
How do I know if I have "sandwich" flooring? I have a 2015 octane 273. It seems like I have thicker wood on top with expanded polystyrene (crumbley white stuff like in coolers) in between and pretty thin wood underneath. Not real sure of the wood thicknesses but maybe 5/8" on top and 1/8" on bottom with some membrane underneath for waterproofing I presume.