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HeadWest · 06-17-2014, 09:06 AM

I know many Airstream owners have owned square box trailers in the past so I'm hoping for a little assistance. My son has a 2013 Rpod (Forest River) that is taking on a lot of water. Many places are suspect, around several fittings and seems.

I'm looking for suggestions on appropriate sealants/caulks for fiberglass, rubber and metal. We stopped by a local dealer yesterday and they suggested just going to Home Depot and buy any exterior home caulk. I just wouldn't think a lot of these would hold up to the flexing and movement of trailer going down the road. I'm especially interested in the thick, flexible grey stuff that seems common on roof components and that stays pretty flexible and tacky.

Any help on this is appreciated. I'd like to assist him with getting his sealed up especially since I need his help up on the roof of my 2013 International that still has too many leaks.

msmcv51 · 06-17-2014, 09:30 AM

The last square box travel trailer we had a serious leakage problem. It would stay sealed only if it did NOT move. It was the second major reason that we bought an Airstream. I told the people that bought it that it was a stationary trailer not to be towed traveling. I have used two products on our house and a couple of rentals we own. The one is called through the roof and the other Big stretch. I found mine at the local hardware in Bedford Michigan, just north of Toledo, Ohio on Secor Rd. With a trailer that new, I would get with Rpod and Forest River about the leakage.

HeadWest · 06-17-2014, 09:49 AM

Not real encouraging with your experience. Unfortunately it was purchased used, out of its one year warranty which I don't think was even transferable. I kind of doubt Forest River will do much for him.

wahoonc · 06-17-2014, 12:39 PM

Dicor is one product. The current SOB market seems to be using more and more silicone. Not sure how that is going to work out for them. I just bought an SOB so I will have to look and see what their recommendations are.

As a general rule I have found that the leaks are usually caused by crappy workmanship. To truly fix the leak, you have to take things apart, clean and apply the sealant where it is supposed to be then reassemble things in the correct order. Gooping large gobs of sealant on screw heads is minimally effective when the screw threads aren't sealed.

Aaron

lewster · 06-17-2014, 01:14 PM

Dicor has a very high VOC content and shows age cracks within 2-3 years. The best self-leveling sealant I have found is SikaFlex 751, which is a silane terminated polymer that does nog dry out and crack.

Foiled Again · 06-17-2014, 01:24 PM

I see many Moho's that use a rubber roof system. I've never seen the whole process done, but isn't it two or three layers? mastic, rubber membrane, finish coat? (sort of like a built up tar roof?)

It might be ugly, but if you used something like that and lapped it over the edges a couple of inches, then carefully reinstall all of the roof vents, fans, etc wouldn't that be a fairly good solution for an SOB? Of course windows and doors would also need to be sealed too.

Paula

**Kevin245** · 06-17-2014, 01:36 PM

We use Diccor on our 5er. It comes in non-sag and self-leveling formulations. The thing about any RV is that they all require preventative maintenance to prevent leaks. We survey our rigs twice a year and there is always something that needs to cut/trimmed and resealed.

A PO's neglect often reveals itself within just a few years.

Good luck and regards,

Kevin

m.hony · 06-17-2014, 02:46 PM

We had a Forest River Wildwood 28RLSS before the 'Stream, and it was a leaker.
It was also the down payment on the Airstream.

wahoonc · 06-17-2014, 03:21 PM

Quote:

Originally Posted by Foiled Again

I see many Moho's that use a rubber roof system. I've never seen the whole process done, but isn't it two or three layers? mastic, rubber membrane, finish coat? (sort of like a built up tar roof?)

It might be ugly, but if you used something like that and lapped it over the edges a couple of inches, then carefully reinstall all of the roof vents, fans, etc wouldn't that be a fairly good solution for an SOB? Of course windows and doors would also need to be sealed too.

Paula

The "rubber" roofs are usually adhered to a substrate (plywood) with bonding adhesive aka contact cement. No finish coat just the completing the details around vents and such.

I have put some very expensive PVC roofing material on one of my guy's 5ver, it is a fleece back and fully adhered, the dealer wanted somewhere around $1600 to replace existing white EPDM and would only give a 2 year warranty (maybe). The stuff we used will be there 30 years from now if the rest of the camper holds up.

Lewster, thanks for the heads up on the sealant. I will pick up a couple of tubes ASAP!

Aaron

lewster · 06-17-2014, 08:45 PM

Paula,

Actually, there is less material involved than you would think. I do a lot or roof replacements and re-coatings while in FL, as the UV there eats a rubber roof in less than 5 years. We have been using a rubber-specific re-coating system that seems to add 4-5 years to the life on the EPDM.

When the factories install a new EPDM rubber roof, they start with a plywood base on top of hopefully aluminum rafters, but I have also seen more wood that I like to admit. The entire roof is sprayed with a special bonding agent (or should be!) special mastic is then applied and then the EPDM sheeting is rolled out onto the roof, where it gets squeegeed to apply pressure to facilitate the bond. That's it!

When I do a re-roof, after removing everything on the roof, I typically add a new layer of 1/4" luan ply right over the existing rubber roof. This provides a clean, smooth surface to apply the new rubber material.

That's the process in a nutshell.

Aaron,

The fuzzy backed stuff os not technically rubber, but TPO (Thermo Plastic Olefin). It needs it's own specific adhesive......but it's not (or shouldn't be!) contact cement. It's more like a thinner bodied flooring cement that either gets rolled on or sprayed on

Quote:

Originally Posted by Foiled Again

I see many Moho's that use a rubber roof system. I've never seen the whole process done, but isn't it two or three layers? mastic, rubber membrane, finish coat? (sort of like a built up tar roof?)

It might be ugly, but if you used something like that and lapped it over the edges a couple of inches, then carefully reinstall all of the roof vents, fans, etc wouldn't that be a fairly good solution for an SOB? Of course windows and doors would also need to be sealed too.

.

Paula

lewster · 06-17-2014, 09:49 PM

EPDM rubber roofs are a simple affair with a plywood substrate, a layer of special mastic and then the EPDM membrane. Only one real layer over the plywood which is often 3/8" and too thin and flexible.

Quote:

Originally Posted by Foiled Again

I see many Moho's that use a rubber roof system. I've never seen the whole process done, but isn't it two or three layers? mastic, rubber membrane, finish coat? (sort of like a built up tar roof?)

It might be ugly, but if you used something like that and lapped it over the edges a couple of inches, then carefully reinstall all of the roof vents, fans, etc wouldn't that be a fairly good solution for an SOB? Of course windows and doors would also need to be sealed too.

Paula

S

wahoonc · 06-18-2014, 04:28 AM

Quote:

Originally Posted by lewster

Aaron,

The fuzzy backed stuff os not technically rubber, but TPO (Thermo Plastic Olefin). It needs it's own specific adhesive......but it's not (or shouldn't be!) contact cement. It's more like a thinner bodied flooring cement that either gets rolled on or sprayed on

Lewster,

I am a professional industrial roofer by trade. The RV industry uses TPO, the stuff I used was Fibertite which is a PVC/Kee based product. It is the top of the line when it comes to the weldable membranes. I know the adhesive isn't really contact cement, but that is the easiest way to describe it. There are quite a few different adhesives used depending on the owner and the conditions, from good old stinky yellow stuff all the way down to the white water based. Each has it's advantages and disadvantages.

I doubt you will ever see Fibertite used by the RV industry it is too expensive.

Aaron

perryg114 · 06-18-2014, 06:09 AM

I have found the design of SOB trailers promotes leaks. The metal trim at the corners has about a million screws that leak. The putty tape that they use under the trim starts to gap pretty soon after it leaves the factory. Unless you completely cover this trim with some sort of flashing, I can't imagine one staying leak free for long as the aluminum skin expands and contracts with every day/night cycle. A rubber skin will be full of holes where the screws penetrate it at the corners. This is one reason I bought an Airstream.

Perry

lewster · 06-18-2014, 08:22 AM

Quote:

Originally Posted by wahoonc

Lewster,

I am a professional industrial roofer by trade. The RV industry uses TPO, the stuff I used was Fibertite which is a PVC/Kee based product. It is the top of the line when it comes to the weldable membranes. I know the adhesive isn't really contact cement, but that is the easiest way to describe it. There are quite a few different adhesives used depending on the owner and the conditions, from good old stinky yellow stuff all the way down to the white water based. Each has it's advantages and disadvantages.

I doubt you will ever see Fibertite used by the RV industry it is too expensive.

Aaron

You are so right about that! Keep it cheap so the units only last 8-10 years and you need to buy a new one. Disposable....for sure!

Foiled Again · 06-19-2014, 03:21 PM

Seems like a marketing opportunity for "RV CONDOM"

lewster · 06-19-2014, 04:25 PM

Paula,

Great idea....... They already have slide-out condoms! Waterproof fabric attaches the the sidewalls of the coach and then the slides. Covers all possible points of water intrusion. :-))