Can Anyone Tell Me What Year....

pnichols wrote:
Well ... going by these links relating to features and frame construction showing that Winnebago, for one, does indeed use complete framing above the floor. I may have been wrong, as perhaps the framing is steel and not aluminum - although I may be confused about their Class A construction materials versus their Class C construction materials. Actually, I prefer steel, but is does weigh more and does rust.

The frame schematic on the left of the first link below is clearly the innards of a typical Winnebago-built Class C ... showing an extensive frame above the floor:

http://www.goitasca.com/products/2014/spirit_spirit_silver/key_features/superstructure/

http://www.goitasca.com/feature_comparison

Those drawings are misleading because those metal pieces are not assembled as a frame, and then the walls covered and filled. That is an assembly, for demonstration, of the metal stiffening pieces enclosed in separately laminated wall and ceiling/roof panels, which later in construction are interlocked and fastened with metal screws.

Go to the factory and watch how those "frames" get bonded into the walls, which derive their strength primarily from the foam cores. Then watch how the walls are hung onto the side of the floor, and the roof set onto the walls.

Winnebago, at least, has interlocking joints where these metal pieces of each panel fasten to other panels. Most other manufacturers using laminated panels depend entirely on the fasteners to hold the structure together.