[Festus2]

As far as the tanks are concerned, I believe that they are not insulated but simply enclosed. On our previous 5th wheel, they were sprayed with insulation and also enclosed - a nice feature. I haven't had occasion to take off the plastic underbelly to examine the tanks to see if they are indeed insulated. Perhaps someone who has had to access the tanks can chime in and clarify whether or not the holding tanks are insulated with styrofoam of some sort - sprayed on most likely.