I am replacing the awing rails on my coach. The roof is EPDM and is held in place by the rails. As such I will need to seal behind the rails to insure water does not wick up behind the rails under the EPDM and into the coach walls and roof. My choices for sealing tape are putty, butyl, or PVC.
Which should I use?
2006 Hurricane 31D aka 'Moby' the Whale
FCC(SW) US Navy Retired 1980-2003
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I believe that butyl is a lot better than the putty in the long run. I don't know what you mean by PVC. Silicon would be another option, but once you put it on, it is almost impossible to use something else over it including silicon.
Butyl putty tape is a lot different from the usual putty tape. It looks similar but is very stretchy.
I have seen two types of butyl tape used on the rails.
One is the light colored Butyl putty tape.
The other is a much firmer (hard to stretch and very hard to pull apart) black butyl tape with an adhesive on one side. I suspect it is used because it can be stuck to the coach making the installation easier.
I would definitely use stainless steel screws as recommended above by John.
Clay (WA5NMR), Lee (Wife), Katie (cat).
Full Timing in a 2004 Winnebago Sightseer 35N, Workhorse chassis, Honda Accord toad
Pulled one rail last night and the coach builder used putty tape behind it. The rail came off very easy. I suspect if I use butyl or PVC future removal of the gutter rail isn't going to be as easy as last night.
Stainless hardware is in the plan and sealing the top of the gutter to the roof line also. The hardware I removed was steel self drilling screws and all had a good layer of corrosion. Plan to use sealant on the threads even with the stainless just to get a good water tight seal in the screw hole.
Still wondering what the difference is between butyl and PVC? Local RV supplier has all three.