Welcome to the forum
What youíre describing is called batten trim. Itís a wood strip that is covered with seam tape, and I have seen it fail numerous times. Depending on the year your trailer was made you can get seam tape and make your own, but normally you have to buy 25 foot rolls. Danny has a good alternative.
2012 Copper Canyon 273FWRET being towed by a 1994 Ford F350 CC,LB,Dually diesel.
Airlift 5000 bags, Prodigy brake control, 5 gauges on the pillar.Used to tow a '97 Jayco 323RKS.
Now an RVIA registered tech. Retired from Law enforcement in 2008 after 25+ yrs.