Georgia-Pacific's Prime Trim and
Temple-Inland's Trim Craft are both
pre-primed, 5/4-inch wood-fiber trimboards.
The wood-fiber material is
similar to hardboard, but don't let
that bias your expectations. I soaked
a sample of each product in water for
a week. While I expected the boards
might turn to mush, the Georgia-
Pacific product hardly swelled, and
the face was barely soft enough to
scratch with my fingernail. The Temple-
Inland product was a little softer
and the edges started to chip after
pulling it from the bath. But the test
suggests both materials would hold up
as fascia and skirt trim, even when
the gutters overflow, or where splashback
is a problem. The boards are
pre-primed on all sides, and