I asked Roadtrek to explain what they meant when they said they had other reports of floor getting hot. Here is their response.
The catalytic converter and output is directly below that area. The cat does get hot under normal use as its job is to burn any unburned fuel in the exhaust fumes by getting even hotter than the exhaust. When poor quality gas is used or a vehicle is out of tune or burning oil, the cat has more fuel to burn and so gets even more hot than normal. These devices can reach temperatures of 600 degrees to 1,000 degrees Fahrenheit. When the vehicle is moving, a lot of that heat is "scrubbed" away by the moving air under the vehicle, but when stopped after driving it has nowhere to go and so will soak upward into everything.
This is not anything that was caused by anything Roadtrek did. The floor in that area in a standard unmodified van will still get warm or hot depending on the operation of the vehicle. Normally people would not be walking around in bare or stocking feet in a cargo van though and so it would not be something reported.
Hope this helps,
Peter Lange
Service and Warranty Specialist
Roadtrek Motorhomes Inc.
1-888-ROADTREK (762-3873)