Using eternabond on the seams at the front and rear ends?

[Larry-NC]

Originally Posted by primo20

Did the same. Just clean where you putting it really well to promote adhesion.

One of the Eternabond kits I got included an abrasive fabric that is similar to the Scotchbrite green kitchen scrubbers, but just a bit coarser. If yours doesn't have that, then go for the Scotchbrite.

[markb422]

While on the roof and being proactive about future roofing issues, has anyone noticed stretch marks of their roofing material. Last year while heading west to Utah I noticed a number of rigs going in the opposite direction and the roofing near the front was ballooning. I even saw one 5th wheel rig that the roofing had torn loose and was flying in the wind like a flag on a windy day. The owner probably had no idea it was doing that. When we got home I got on the roof and noticed in a couple small areas that the roofing was loose from the substrate where it could have been ballooning a little but there is a roof vent in the middle about 2 feet back from the front cap. Also there seemed to be a spot with stretch marks along the edges of the roof.

[Larry-NC]

Originally Posted by markb422

While on the roof and being proactive about future roofing issues, has anyone noticed stretch marks of their roofing material. Last year while heading west to Utah I noticed a number of rigs going in the opposite direction and the roofing near the front was ballooning. I even saw one 5th wheel rig that the roofing had torn loose and was flying in the wind like a flag on a windy day. The owner probably had no idea it was doing that. When we got home I got on the roof and noticed in a couple small areas that the roofing was loose from the substrate where it could have been ballooning a little but there is a roof vent in the middle about 2 feet back from the front cap. Also there seemed to be a spot with stretch marks along the edges of the roof.

A vehicle at speed pulls quite a bit of vacuum (lift) on the roof.

This is why they become unstable at excessive speeds--not enough weight on the tires for good grip. It is also why the most economical cars are teardrop-shaped--it reduces the vacuum and corresponding drag, and why some cars have spoilers at the rear--doesn't reduce the drag, but does force the rear end down. (Sorry for the aside.)

The membrane is glued to the roof with contact cement. It's important that this be done well to prevent ballooning and subsequent rupture, just as you note. It it was done poorly at the factory, it should be repaired under warranty.

It can be complicated, as it requires removing the rain gutters and awnings and the caulk and trim across the front and rear. There is butyl tape under the rain gutters which is a pain to work with.

Some folks even say that a second coat of contact cement won't stick to the first coat which implies replacing the entire roof membrane and maybe the decking. And of course that implies removing all the vents, antenna, ladders and everything else on the roof--more caulk and butyl tape to deal with.

[bclinton]

Rear cap done. Looks like it will help and was fairly easy to do. I need to order more tape and will do the front next week

[Larry-NC]

Originally Posted by bclinton

Rear cap done. Looks like it will help and was fairly easy to do. I need to order more tape and will do the front next week

Looks good. For the very best application (you can still do this), you roll the tape down to improve the adhesion coverage. Eternabond has a very expensive roller, but you can use this inexpensive wallpaper seam roller from Lowe's.

[bclinton]

I'm wondering.....has anyone done similar to the side seams? There's not a lot of area to put tape and that includes the gutter so I'm not sure what I could do to that long area on each side...

[rsdata]

I put tape on the roof side seams and lapped it about 1/4 to 1/2 inch ( somewhere in that range) into the gutters... so the tape width extends from the rubber roof, over the seam and into the gutter, not into the bottom of the gutter

[Larry-NC]

Originally Posted by bclinton

I'm wondering.....has anyone done similar to the side seams? There's not a lot of area to put tape and that includes the gutter so I'm not sure what I could do to that long area on each side...

Explain the side seam issue to me

At the sides, the membrane overlaps outside the siding. A layer of butyl tape is applied between the siding and the rain gutter. Any water that runs off the roof should be stopped by the butyl tape.

The real area of vulnerability is those awful awning clamps that bridge the rain gutter. There is REAL water intrusion at every one of these clamps. If you don't believe me, take out one of the lag screws. It will be rusty for its whole length. This is a bad design.

On a wood-frame trailer, the lag screws go into a 1x2 that sits atop the 2x2 wall header. The 1x2 serves to tie all the roof trusses together. Water goes into the 1x2 and ruins it, then wicks up into the trailer roof. Trailers that have been stored outside for any length of time will have soft spots in the roof decking right by those awning brackets.

DW loves her awnings. If I had my way they wouldn't be there. In fact, I sold the awning from the Cherokee and covered the mounting holes with Eternabond. DW will surely insist that I keep the awning on the SOB.

[WFD]

Planning on applying eternabond to the roof this spring. Roof is tan. I know eternabond is available in tan but it doesn't seem to be as available as it is in white and seems more limited in widths, and as a result seems pricier than the standard white. Has anybody applied the white to a tan roof? For the most part it won't show from the ground but it would in the front where the roof meets up with the front cap. Just wondering what it would look like.

[Larry-NC]

Originally Posted by WFD

Planning on applying eternabond to the roof this spring. Roof is tan. I know eternabond is available in tan but it doesn't seem to be as available as it is in white and seems more limited in widths, and as a result seems pricier than the standard white. Has anybody applied the white to a tan roof? For the most part it won't show from the ground but it would in the front where the roof meets up with the front cap. Just wondering what it would look like.

Take a photo and manipulate it on your computer, the so-called "Photoshop technique."

If you don't know how to do that, post the photo here and someone will do it for you.

[rsdata]

white and seems more limited in widths, and as a result seems pricier than the standard white. Has anybody applied the white to a tan roof? For the most part it won't show from the ground but it would in the front where the roof meets up with the front cap. Just wondering what it would look like.

I don't know that I would care much what others thought about the way my trailer looks as long as I was pleased... spend the money for the tan on the front if it makes you feel better. On the other areas of the roof, only people looking down from bridge overpass will know you went cheap with the white.

[Larry-NC]

Originally Posted by WFD

Planning on applying eternabond to the roof this spring. Roof is tan. I know eternabond is available in tan but it doesn't seem to be as available as it is in white and seems more limited in widths, and as a result seems pricier than the standard white. Has anybody applied the white to a tan roof? For the most part it won't show from the ground but it would in the front where the roof meets up with the front cap. Just wondering what it would look like.

Remember, wider is better. The more surface area, the better the adhesion. Don't forget to use a roller after application.

[rsdata]

Remember, wider is better. The more surface area, the better the adhesion. Don't forget to use a roller after application.

2 inches is pretty wide when you are only covering a 1/4 inch wide roof seam. The edges on my 4+ year old install of Eternabond are not lifting at all, so installing 4 inch wide tape when 2 inch will do is not necessary IMHO.

And I am talking about a frontal leading edge on my trailer roof line that I believe would get the most wind and certainly, considering on how I store it with the front facing south, it also gets the most sun. Now I have not checked since I was in FL in February, but Eternabond was still strongly adhered to the Gel Coat lapped to the roof membrane at that time. I would go out now and take a picture, but this cold front that just came through has dropped temps into the 40's with significant wind-chill in the Ohio Valley.

Eternabond is not hard to install. Just make sure the surface your applying to is clean and you press it down with a roller as Larry-NC has mentioned.

INSTALL instructions for RV's here...
https://www.eternabond.com/articles.asp?id=166

[Larry-NC]

Originally Posted by rsdata

2 inches is pretty wide when you are only covering a 1/4 inch wide roof seam. The edges on my 4+ year old install of Eternabond are not lifting at all, so installing 4 inch wide tape when 2 inch will do is not necessary IMHO.

It depends on the transition. On the SOB Nash which I am rebuilding, a metal transition strip about an inch wide and 1/4-inch high spans the metal front and the EPDM membrane that's tucked under it. If I were to attempt to cover that with 2-inch tape, I would have about 1/2-inch of actual contact on each side.

A similar situation exists where there's a wide band of uneven Dicor Lap Sealant on our Cherokee. I would like to see at least an inch of even, level surface coverage on each side of the joint.

[wharfrat48]

Anyone use the eternabond primer (Eternaprime I think) before application? I would assume just cleaning would be sufficient, but wanted to check with the experts. Thanks

[rsdata]

It depends on the transition.

Well that does make sense... mine is not that wide... 1/4 to 1/2 inch at most.

Anyone use the eternabond primer (Eternaprime I think) before application?

I did not use primer... I used a terry cloth and Mineral Spirits which took off grime very easily ( made lap seal look like new), then hit it again with another cloth soaked with IPA ( use the higher alcohol stuff like 91%) to wipe off the Mineral Spirits left behind. In about a minute the surface was dry and ready for application of the tape. Do not leave Mineral Spirits on the rubber roof... it will swell the rubber (TPO, EPDM), but a wipe on to clean then a quick wipe off with IPA (from drug store counter) will not hurt anything.

[Scrapper]

There are Eternabond instruction documents in the forums Library > Awnings, Roofs and Exterior
https://www.forestriverforums.com/fo...do=file&id=213
https://www.forestriverforums.com/fo...do=file&id=211

More detailed instructions, videos and ordering: https://www.eternabond.com/default.asp
Eternabond Installation Instructions: https://www.eternabond.com/articles.asp?id=166
Online Video Library: https://www.eternabond.com/articles.asp?id=200
Eternabond Article Library: https://www.eternabond.com/articles.asp?id=132

[SailorSam20500]

Originally Posted by WFD

Planning on applying eternabond to the roof this spring. Roof is tan. I know eternabond is available in tan but it doesn't seem to be as available as it is in white and seems more limited in widths, and as a result seems pricier than the standard white. Has anybody applied the white to a tan roof? For the most part it won't show from the ground but it would in the front where the roof meets up with the front cap. Just wondering what it would look like.

This is heresy on this site, but...
You could consider clear flex tape for the front cap area. It will likely turn an amber-ish color over time. No idea if it would have the same life as Eternabond. If you go this way, keep us appraised of how well it works. The manufacturer is obviously selling a lot of their stuff...

[CincyGus]

Originally Posted by Larry-NC

Explain the side seam issue to me

At the sides, the membrane overlaps outside the siding. A layer of butyl tape is applied between the siding and the rain gutter. Any water that runs off the roof should be stopped by the butyl tape.

The real area of vulnerability is those awful awning clamps that bridge the rain gutter. There is REAL water intrusion at every one of these clamps. If you don't believe me, take out one of the lag screws. It will be rusty for its whole length. This is a bad design.

On a wood-frame trailer, the lag screws go into a 1x2 that sits atop the 2x2 wall header. The 1x2 serves to tie all the roof trusses together. Water goes into the 1x2 and ruins it, then wicks up into the trailer roof. Trailers that have been stored outside for any length of time will have soft spots in the roof decking right by those awning brackets.

DW loves her awnings. If I had my way they wouldn't be there. In fact, I sold the awning from the Cherokee and covered the mounting holes with Eternabond. DW will surely insist that I keep the awning on the SOB.

The main issues I've seen on used RV's that I've looked at with side seam issues are as follows:

1) The edges of the decking were not rounded and are a sharp corner that has rubbed/cut the rubber roof on the corner as it rolls from roof to sidewall, above the gutter. Generally right on the leading edge of the top of the decking, you will see it split. As RSDATA stated, That's exactly what I plan to do once I get a warm dry weekend off work on a 18 month old trailer because I can feel the non-rounded corners of the decking and know it will at some point rub through and tear the rubber roofing. I'll be using 2" tape as with the transition I don't want too wide a piece that it becomes unworkable.

2) Is similar to what you describe with the awning lag bolts except the screws in the actual gutter are the culprit. When I do the sides, the plan is to tighten all the gutter screws slightly (as they have a tendency to loosen up), run the tape over the heads of the screws inside the gutter pressing firmly with my fingers along that edge of the eternabond since a roller won't work there and then rolling the rest back onto the roof over the corner.

I appreciate you bringing up the awning attachments as now I believe I'm likely to loosen them enough to have a look and either apply butyl tape, non-sagging dicor or small strips of eternabond tape behind them and tighten them back down.

Water penetration is one of the things other than something catastrophic (Accident/Fire/Flood/etc) that can really destroy a RV's value. And it can get away from you before you recognise that you have a problem if your not doing inspections regularly. Learned that lesson the hard way on my first used RV. Luckily it only cost me $4000, not $40k. At this point, I'm all about doing a quarterly inspection (except winter) and being proactive BEFORE I have a problem.

[Larry-NC]

Originally Posted by SailorSam20500

This is heresy on this site, but...
You could consider clear flex tape for the front cap area. It will likely turn an amber-ish color over time. No idea if it would have the same life as Eternabond. If you go this way, keep us appraised of how well it works. The manufacturer is obviously selling a lot of their stuff...

The color change indicates a change in the chemical or physical structure.

It seems unlikely that the change is improves any of the characteristics. UV light is a powerful agent.