We bought a Northstar camper in 2016. The manufacturer, Rex, uses butyl tape extensively. It has oozed out of cracks and around jack plates, etc. as expected. Only certain areas have actual caulk/silicone (ex. tops of windows, roof, penetrations, inside edge of nose trim and area under nose).
I recently reapplied some Dicor on a few screwheads on the roof where the caulk was wearing a little thin. Otherwise it all looks great. Today while looking at the outside corner trim on the nose, I noticed that chunks of very dirty butyl tape had flaked out leaving up to a 1/8" gap between the sidewall fiberglass and the plastic trim piece. I'm assuming there is plenty more butyl tape down in behind there, however, I don't like the idea of water getting into that horizontal groove and meeting my wood.
When we pulled out the rubber trim to expose the screw heads that hold the plastic corner trim in place, 2 of the screws had discoloration on the heads and were rusty all the way at their tips. These 2 screws are immediately in front of the first little weep hole in the rubber trim. So, since it is kind of a low point there, is the rust due to water getting behind the rubber "flashing" and wicking up the screws before the weep hole, or is water getting in the butyl rubber gaps from above?
The pics show a small gap in butyl and an area where I just temporarily squished in some excess butyl in the big gaps.
With monsoon season almost upon us, do I need to pull the whole corner trim and put on a fresh length of butyl tape? Do I clean up the area as best I can and run a non-sag bead of Dicor over the entire length? I'd ask Rex or Bill at TCW, but I can't wait 2 months for an answer ;).
Thanks!
2014 Ram 3500 CrewCab Diesel DRW 4x4 4.10 Aisin, Torklift Fastguns, Upper Stableloads, Timbrens
2017 Northstar 12' STC
640W solar, 400Ah lithium LiFeMnPO4 batteries