My 2015 Wildcat MAXX has an enclosed undercarriage and the pipe openings are foamed. If you cut away any of the undercarriage material you'll find it has a insulation layer bonded to the underlay. The tanks are "heated" by a furnace run which does dump some amount of hot air into the enclosed undercarriage area when the furnace is running. Not exactly a 4 season solution to cold weather, but better than nothing!
Days camping (2015)----88 days
Days camping (2016) ---110 days
2016 Wildcat MAXX 28RKX (33' TT), 2007 13' Scamp
2015 Ram Laramie Hemi
30 years RV'ing
12 different RV's