I have just had built a small (8x14) free standing storage shed. All of
the exterior siding and trim is pressure treated. I am wondering just how
good pressure treated wood is. I was told by the builders that since it
was all pressure treated, I could leave the natural wood look or I could
prime and paint it. I like the natural wood look and don't want to paint
it. But I want to know if I should apply Thompson's Water Seal or similar
or if it is okay just leaving the pressure treated lumber as is.

TIA

James