Filling Nail Holes in Azek Trim

Installation tip for cellular PVC trim nailing. March 3, 2010

Iím looking to fasten Azec to OSB by nailing a mullion in between two windows outside. How do you cover up the hole the fastener made? I donít think finish nails from a gun and silicone is the answer. Also, how about filling the holes? Something told me to use trim screws, stainless of course.

Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor D:
I replaced 15 windows in a house about six months ago and trimmed them with Azec. I used stainless trim nails and filled with good 35yr latex caulk (owner did not want to paint). The Azec was white. I looked at the job other day and you can just barely see the filled holes.

From the original questioner:
Thanks for your response. Although Iíve been doing this all my life (a long time) there is always room for learning especially with new stuff. I love the forums because you talk to experience in various situations. After 40 plus years I still scratch my head and wonder what to do.

From contributor R:
Another option which you may consider especially this time of year with the cold is using "headcote" stainless trimhead screws. They do a good job color matching the Azec. I work with a builder on occasion and thatís what he uses all the time. Granted the heads are exposed (flush) but with the color match they blend pretty well and you donít have to pre drill or worry about the Azec splitting on the last nail of that 16 foot run because itís too cold. Also it is getting a bit cold for the caulking to set up outside.

From Gary Katz, forum technical advisor:
PVC moves so much from thermal expansion and contraction that trim nails or finish nails won't hold it still. Best to use SS trim-head finish screws. You can use Bond-and-Fill to fill the nail holes. The color is almost a match for Azek.