UV-A and UV-B light penetrates poorly through anything that is tinted. Also
tightly woven materials do not allow penetration. Most of us have had "tan
lines" at some point with your skin being pasty white under your bathing
suit or shirt while the exposed areas are tan or burned.

With a reflective white coating on the outside and the opaque nature of
fiberglass it is highly unlikely that any substantial amount of UV light
gets to the inside of anyones trailer. If anyones wishes to have references
for the science of it all just let me know.

Casey Lenox
KC
Phoenix