This will vary with the model of RV, but most of them are pretty well insulated. Most have a metal frame with sheet foam between. The outside skin is usually fi

This will vary with the model of RV, but most of them are pretty well insulated. Most have a metal frame with sheet foam between. The outside skin is usually fiberglass, which makes a good vapor barrier. The volume to heat is pretty small so it's efficient. The biggest problem in really cold weather is condensation on inside of the windows. Some of the more expensive RVs have dual-pane windows with don't have this problem and are even more efficient. Road handling varies. Most RVs are heavy which aids snow traction. And rain isn't a problem either (except for the noise). But wind -- that's a problem. Most RVs are tall and boxy. RVs with long a wheel-base in relation to length do better in wind than those with large overhangs aft of the rear axle. I found that the faster I go the worse the handling in stiff cross-winds. Slowing down to 55mph helps a lot. Cross-winds are the worst. Headwinds suck your milage down (a lot) but a tailwind will help.