Roof Repair Project (Advice needed)

[jondoexxxx]

Hi,

I am a newbie, just bought an 88 Minnie Winnie with 75k miles and first thing I wanted to do was fix some issues with the metal roof.

I pulled off a cargo box that was installed as it seemed like it was going to leak and patched the holes with Heng's Alkyd Fibered Roof Coating - Elasto-White.

Next up I need to repair some areas where the seams on around the sides, vents, etc. is cracking and coming up.

I started with just a scraper, but found that the hard roofing material that was used before was put on top of some sort of caulking and wouldn't really chip off very well. I ended up using a heat gun to loosen the material and then was able to scrape most of the caulk and roofing material off.

What I am wondering is whether I should continue to scrape and then maybe sand down to the raw roof metal / siding? Or if I am good to just use the Roof Coat on top of the thin layer of caulking that remains? Should I apply a new bead of silicone or other rv caulking and then apply the roofing agent?

I am hesitant to get too much further down this rabbit hole, but also don't want to do a bad job.

Any advice would be greatly appreciated!

[TenOC]

Coat the complete roof with Liquid EPDM RV rubber roof. Maybe two coats in the "bad" places. See link below. One of the videos is of my 33 foot TT I did in 2010. No leaks for 5 years.

Watch the videos in the RV section

[westend]

Dicor and Eternabond is kind of a "belt and suspenders" type of deal. I've found that the Eternabond tapes seal where tube sealants don't. One thing to remember is that Eternabond needs a really clean surface to adhere well. Any silicone or other stupid patch products need to be removed. I spent many a happy hour making sure that was happening. Actually, I broke the job down into smaller, manageable pieces so I wouldn't get burned out on it.

Good luck on the roof repairs.

[jondoexxxx]

First off thanks for all the advice. I am thinking I will continue with the heat gun to remove the bulk of the calk and roofing material, then use a grinder / sander to remove the remaining pieces.

Then I will attempt to remove additional caulking left on the roof with mineral spirits and then acetone.

If there are areas where I cannot fully remove old caulking, would you all recommend priming and then using eternabond, then covering with the Hengs roof coat?

Should I use the bead of Dicor or other sealant before the Eternabond / primer or just go straight to the primer and eternabond?

Also, here is a pic of the RV, with me on the roof (where I will undobutedly be for the next few weekends 😉 .

[westend]

downtheroad wrote:
Welcome to the Forum...
I'd also be concerned about what could be happening under that roof...Looks like it could easily have been leaking. If so, you could have problems between the roof and ceiling inside as well as in the walls.

Right, but it's not "could have problems", more like "will have problems". When I repaired my Starcraft, victim of long term leaks and poor maintenance procedures, I replaced a dozen rafter ends that had rotted off the top wall plate. A quick push up on the ceiling surface will diagnose the integrity of the rafters, they will move upward with little resistance.

[dieharder]

Yeah, your "before" pictures scare the bejaysus out of me. Don't mean to scare you but I have to give you the reality.

Reminds me a lot of how my first RV looked like when I bought it and didn't know better. Never checked the roof and, once I went up there to look, looked like that. Had an RV shop take a look at it and they told me that the roof under that mess was finished and rotted. they didn't do it to try and get a sale or work out of me, it was just to tell me that the RV wasn't worth putting a darn cent into. Lesson learned - expensive one at that.

[Mich_F]

downtheroad wrote:
Welcome to the Forum...
I'd also be concerned about what could be happening under that roof...Looks like it could easily have been leaking. If so, you could have problems between the roof and ceiling inside as well as in the walls.

X 2
It certainly looks like it's been a long time since that RV has seen any preventative maintenance. Duct tape on a vent cover? :S

[Cloud_Dancer]

I've found that self-leveling goop does NOT work like some people thing it works.
Nor is it needed. The removal of all of it, and the proper cleaning of the seam area, plus a proper application of a narrow bead of 3M 4200 adhesive/caulk(non-silicon), is the proper preparation for the installation of 4" EternaBond. This procedure is much more longer-lasting than any other.

note: everyone has their own opinion of how to fix this kind of roof problem. I'm simply offering mine.

[downtheroad]

Welcome to the Forum...
I'd also be concerned about what could be happening under that roof...Looks like it could easily have been leaking. If so, you could have problems between the roof and ceiling inside as well as in the walls.

[JPeyton]

westend wrote:

JPeyton wrote:
I could be wrong, but the black stuff they put on I thought was for rubber roofs (or it may be the white stuff but just old and burnt from the sun... I think I remember some looking that way). Assuming you have the vinyl (I'm not 100% sure) then the acrylic stuff you have is right. That stuff works great. Just keep in mind that if it flexes too much (when you walk around the area) that it may crack. But that sealant you mentioned is flexible to some degree. Great stuff. Just clean it up the best you can and blob it on there good and let it dry and it will hold. Works like a charm and holds up for two or three years easy.

I've got to ask since I can't get my head around this---why would you think a product is "great", that after two years, fails to seal the area it was intended to seal? Is it because of the ease of application?

Fair question. Because the sun/rain are bastard childs of Satan, they ruin everything. I've been doing this for 12 years.

Certainly that stuff lasts longer, but 2 to 5 years is ok. I was being conservative in my estimate. It starts to crack a bit if left out in the sun a long time. Leaks are worse than a Chinese drip torture.

[westend]

JPeyton wrote:
I could be wrong, but the black stuff they put on I thought was for rubber roofs (or it may be the white stuff but just old and burnt from the sun... I think I remember some looking that way). Assuming you have the vinyl (I'm not 100% sure) then the acrylic stuff you have is right. That stuff works great. Just keep in mind that if it flexes too much (when you walk around the area) that it may crack. But that sealant you mentioned is flexible to some degree. Great stuff. Just clean it up the best you can and blob it on there good and let it dry and it will hold. Works like a charm and holds up for two or three years easy.

I've got to ask since I can't get my head around this---why would you think a product is "great", that after two years, fails to seal the area it was intended to seal? Is it because of the ease of application?

[westend]

I've done this same job, removing years of different material patchwork off a metal roof. First, put that can of Heng's roof seal on a shelf. You won't be needing that for awhile and it really doesn't act as a joint seal.

The thicker material can be removed with heat gun and scraper, followed by a wire wheel with 4" grinder. After the bulk is removed, wash first with mineral spirits and a plastic scrub pad, followed by lacquer thinner or acetone and a rag. The surfaces should now be clean enough to accept a sealing system.

Initially, I tried sealants in a tube but eventually taped all the joints and through holes in the roof with Eternabond tapes. My roof is now leak-free and has been like that through two Minnesota Winters.

About every other year and sometimes yearly, I check the integrity of my trailer from leaks by performing a pressurized leak test. Search the Forum to see how that is done. It is the most reliable means to see if you have even a pinhole leak.

BTW, there is no place on an RV exterior where silicone should be used. It is the Devil. We use urethane or polymer based caulks like Dicor or Geocel Proflex RV.

[gbopp]

Welcome to the forum and congrats on your Winnie.

For the seams I would use Eternabond. Clean the area well and use a roller when applying the Eternabond.

Don't use silicone caulk. Dicor self leveling caulk does a good job on horizontal surfaces.

Silicone caulk is difficult to remove and nothing will stick to it, including more silicone caulk.

When in doubt, ask questions on the forum. There is a lot of information and experience available.

Enjoy your travels. Where are the pics of your Winnie? 🙂

[JPeyton]

I could be wrong, but the black stuff they put on I thought was for rubber roofs (or it may be the white stuff but just old and burnt from the sun... I think I remember some looking that way). Assuming you have the vinyl (I'm not 100% sure) then the acrylic stuff you have is right. That stuff works great. Just keep in mind that if it flexes too much (when you walk around the area) that it may crack. But that sealant you mentioned is flexible to some degree. Great stuff. Just clean it up the best you can and blob it on there good and let it dry and it will hold. Works like a charm and holds up for two or three years easy.