What type of roof sealant is this?

[Demersus]

Hello everyone, I'm not sure if this is the best forum for general RV maintenance questions. But I didn't find one that looks specific to maint/repair. Let me know if I missed it.

Last spring I purchased my '94 27" Thor Chateau 5th wheel RV. I need to do some roof resealing before I head out again. The roof is a single aluminum sheet with no seams and no coating. But it is sealed with something around the vents, skylight, and at the corners, etc. It's in decent shape overall, so it only needs touch ups.

But I don't know what product was previously used. For 28 years old it looks pretty good, so I doubt that it's all the original sealant. But it's also brushed on and kept fairly neat. The material looks and feels a lot like latex caulk, but I think it is perhaps a polyurethane or other RV specific elastomeric product.

It also looks like it goes on more like a paste than a liquid. And I want to stay with that, since I don't intend to coat the entire roof, at least not yet. And the self leveling lap sealants I've seen look too runny for what I want to do.

I thought about trying a small container of Flex Seal, but I read that it's kinda soft and doesn't really last very long. Whatever is already applied seems very tough. It's a bit flexible, but hard to penetrate and pick at.

Any suggestions or recommendations much appreciated!

[Oregonpharme]

When you get back in time the roof sealants used are not compatible with the new sealants. Whatever you attempt to patch that old sealant will loosen and come off rather quickly. Your best bet is to completely remove the old sealant and start over with a new technology product. You want a product similar toDicor 501LSW-1 Self-Leveling Lap Sealant. You do want self-leveling as it will flow into the seams and joints.

[Bobby F]

I have a '93 with an EPDM (rubber) roof, and the sealant used looks identical to what you have pictured.

I have gone around to all old sealed areas, brushed and cleaned them, rubbed them down with alcohol, and then topsealed them with Dicor Lap Sealant. It's sticking great - seemed to meld with the old stuff after I softened it a bit with the alcohol.

This stuff: https://www.amazon.com/Dicor-501LSW-...2-d605505c9d1e

[Demersus]

Thanks for the pointers. I think I'll strip and clean off the old stuff at the corners were things need patching, and use either a Dicor or Geocel Pro Flex product. All the other areas are still good, so I'll leave them alone until they need work.

[Tomahawk]

You'll be happier with eterna-bond tape. If you are going to make the effort to clean everything up the tape lasts multiple years, the dicor lasts a lot less.
2 cents

[Dave Pelletier]

Originally Posted by Tomahawk

You'll be happier with eterna-bond tape. If you are going to make the effort to clean everything up the tape lasts multiple years, the dicor lasts a lot less.
2 cents

I can't help think of Matt's (Adventurous Way youtube channel) roof leak issues some of which were attributed to the eterna-bond tape failing to seal. I'd stick with Dicor myself. ....and FWIW, the Dicor on the roof of my Bigfoot lasted many years without issue, 3 or 4 at least.

Dave