From the Manufactures site:
Can I use Through the Roof on my camper/RV?
Through the Roof is highly recommended for most surfaces on RV's/ Campers. It can be used on rubber roof membranes; however, while it will adhere as usual to the rubber membrane, it may ripple or warp the rubber membranes over time. Cosmetically, it does not look good, but the performance of the Through the Roof remains the same.
In addition, some RV's / Campers use polyethylene and polypropylene materials. Through the Roof will not stick to them, so keep your eye out.
