Caulking Roof

Don't use silicone on an RV. Use Dicor Self leveling lap sealant!

I just remove the loose caulk and apply the new caulk over the old. I would remove as much caulk as possible around a leaking area before putting on the new.

Always clean well before applying caulk. I Use Dicor self leveling on the horizontal areas.

Well, I just love YouTube. I did a little searching and found this video: Click here. Its hard to believe this was all done in only 7 minutes and 3 seconds!

Good stuff in the video. Maybe it will help you out.

Many people plastic chisel up as much of the old Dicor as they can, and then cover the area with Eternabond tape (Amazon carries it in several widths).

If you have a Winnie type fiberglass roof, which are known to loosen on the edges, wind gets under the thin fiberglass, and rips part of the roof off. So you might consider using 2" Eternabond tape in the J-channel along the edges to prevent that problem. Also, many people use 4" Ebond to seal the front and end cap to the roof.

Here's a link to my blog where I did just that as PM: Fiberglass roof Preventative Maintenance.

Jim@HiTek wrote:
Many people plastic chisel up as much of the old Dicor as they can, and then cover the area with Eternabond tape (Amazon carries it in several widths).

If you have a Winnie type fiberglass roof, which are known to loosen on the edges, wind gets under the thin fiberglass, and rips part of the roof off. So you might consider using 2" Eternabond tape in the J-channel along the edges to prevent that problem. Also, many people use 4" Ebond to seal the front and end cap to the roof.

Here's a link to my blog where I did just that as PM: Fiberglass roof Preventative Maintenance.

If you look at his profile, he has a Tiffen.

want-a-be wrote:
Since I never caulk the roof before I have some questions! This is on a fiberglass roof, when I was at the factory I got some CSL Silicone caulk is that what I use, or do I want the self leveling kind? Also do I remove the old caulk first. We do have a small leak do I caulk over it or remove it before caulking.
Thanks for all comments!

Well,
You don't say what year/make/model/type of coach you have. And, you don't say WHAT PART of the roof you're working on. There are different caulks/sealants to use on different sections of the coach roof. "Self Leveling" is for areas that have no vertical parts or sections. Areas like around vents, seams along front and rear caps etc. But, on the edge(s), you can't use self leveling.

And as far as using SILICONE on any section of the roof, YES, you can, but, there are specifics to using it, and where. If you look at this video, you'll see EXACTLY when and where to use Silicone.
Scott

https://www.youtube.com/watch?v=BJz7doxPQXg

I did mine a couple of years ago and I removed as much of the old caulk as I could. I used a oscillating tool with a flat blade and it takes the old stuff right off. I then prepped the surfaces well for Eternabond tape. You have to follow the directions well on the surface. Before I put the tape on I did use just a small amount of the self leveling sealant. The Eternabond tape won't stick to the caulk so don't use too much, the tape as to stick to the fiberglass. I did that one front and rear seal. On the plastic vents I removed them all and cleaned all the old caulk out and reinstalled them all using the self leveling caulk around the seams just like above and then the tape over the top of that. So far no leaks.

Thanks for all the replies

If your just doing the seams Eternabond tape overlapping the seam will take care of the problem and you will not have to worry about it for years to come. Go to the eternabond web site and watch the video's