Glue my kayaks to the roof?

[MoonTimber]

There are lots of us using 3M VHB (Very High Bond) double-sided tape holding our large solar panels down on the fiberglass rooftops. In fact, AMSolar, in Oregon, is doing this routinely. The panels I have weigh about 45 lbs and are nowhere near as aerodynamic as the bow of a kayak is.

 

I can understand the skepticism. I was pretty nervous about the idea myself. But we cleaned off the oxidation on the gelcoat, then wiped the area briefly with acetone, and set our panel mounts down using just the tape. About 1.5 sq. inches of base plate. They haven't budged in 2500 miles including 500 in a driving wind-and-rainstorm along the western Columbia River Gorge leading into Portland, Oregon last December. I wouldn't have done it this way had not several friends with tens-of-thousands of miles and identical installations convinced me that it would work.

 

No holes = no leaks.

 

We did install in warm weather and then let everything sit for two weeks before we drove the RV anywhere with the panels up there. Even then I had my shoulders hunched listening for any sign of something giving way.

 

WDR

 

Are you saying I can use the VHB tape on the roof and just stick the tie down anchors to them? My roof looks like it has paint or some kind of sealant on it. Wouldn't the tape just rip the paint off the rubbery sheet that covers the wood?

 

I don't know what my roof is actually covered with. I haven't closely examined it. Here is a closer pic though:

[Chad Heiser]

No, you cannot use VHB tape on your roof type. VHB tape can only be used on a solid fiberglass or metal roof. Your roof appears to be covered with a rubber sheeting over wood. You cannot use VHB on this type of roof as the only thing the VHB would be stuck to is the rubber sheeting. The rubber sheeting would quickly peel away from the wood roof substructure and fall off.

[Kirk W]

Are you saying I can use the VHB tape on the roof and just stick the tie down anchors to them? My roof looks like it has paint or some kind of sealant on it. Wouldn't the tape just rip the paint off the rubbery sheet that covers the wood?

 

I don't know what my roof is actually covered with. I haven't closely examined it. Here is a closer pic though:

Looking at your picture it is difficult to see exactly what your roof is made of. No question that Chard is correct if it is an EDPM roof as many of them are. Yours looks to have been painted over with some type of roofing material and there are many such products around so I'd consider that questionable for any double-stick tape adhesion and having owned an RV with EDPM I absolutely would not use tape on it for many reasons. I highly doubt that it would stick at all. Are those brush marks that show or is it just discoloration with a large buildup of caulking material around the ladder mounts?

 

If this were mine, I'd be taking a serious look at some work on the roof before very long as it looks to be in questionable condition.

[mickhoss]

moon timber, when I made the post about using pipe loops I was thinking about having them from one side to the other, after thinking about it I thought they could be constructed from the rear bumper over the top and down again to the front bumper suitabley shaped to miss any thing that would cause a problem, if you had a series of x braces built in to them it may make them rigid enough so as to not have to brace them to the side.

 

if you have access to a pipe bender , welder, and angle grinder and some level of skill you could fabricate

something similar at home.

 

If not your local metal fabrication shop could knock something up for you.

 

Anyhow sometimes a good hair brained suggestion leads to thinking along different lines and you come up with a solution to a problem

 

mick

[MoonTimber]

That's what I was thinking. The roof seems to be a rubber sheet over wood with several layers of unidentified "stuff" over it. Those are brush marks. The right ladder mount is loose, so the rubber lifts an half inch when the ladder mount wiggles. I plan to add another layer of goop before we go on any long trips. I know very little about RV roof repair but we have entered the dry season here in Sacramento, which means it probably won't rain again for another five to six months. The entire state is stuck in a drought and we can be confident of driving anywhere up or down the coast without rain, so I can take my sweet time getting to the roof. We want to drive to Florida in the fall though, so the roof is on my list. There are two windows I don't trust either.

 

Mick,

I don't know how to weld, so I think that would end up being really expensive. That said, nothing prevents me from bolting D hooks to the front and rear bumper to use as fore and aft mounts for the straps, so you have given me an idea, but I'm going to see if I can get hooks installed on the sides first.

[Pat & Pete]

 

If this were mine, I'd be taking a serious look at some work on the roof before very long as it looks to be in questionable condition .

 

X2 ^ ... Definitely not a professional application .

[Smitty77_7]

http://www.irv2.com/forums/f56/solar-systems-236174.html

 

Here is the post where BatteryPro Larry shared pictures of his solar panel bracket mounts to the roof, and how he does it. My thought was using the metal 12" square (or whatever size the came in, could have been 10") to distribute the load around some. The kayaks, will have more wind catching applied force to whatever you use to mount them to the roof:)!

 

I feel for sure it is doable.

 

And yes, that roof has seen better days:)! If it has ever leaded before, you could have soft ares underneath, which will make getting a solid mount more difficult. Good inspection and making the roof covering sound is good input.

 

Best,

Smitty

[Kirk W]

I would make the roofing a fairly high priority as you don't want to have to undo whatever you put up permanently as mountings for your kayaks. On the windows, is there some sign of leaks there to make you suspicious? If so the best fix for most window leaks is to remove the window and replace the butyl caulk tape. You can find that at most RV supply stores or from Amazon.

[skp51443]

Looking at that roof I'd peel it off and put down a new rubber sheet. Not fun or cheap but far more fun and cheaper than dealing with mold and rot in your walls or floor from a leak.

 

While you have it off you could get a better idea of what you have to mount your stuff to.

[MoonTimber]

http://www.irv2.com/forums/f56/solar-systems-236174.html

 

Here is the post where BatteryPro Larry shared pictures of his solar panel bracket mounts to the roof, and how he does it. My thought was using the metal 12" square (or whatever size the came in, could have been 10") to distribute the load around some. The kayaks, will have more wind catching applied force to whatever you use to mount them to the roof:)!

 

I feel for sure it is doable.

 

And yes, that roof has seen better days:)! If it has ever leaded before, you could have soft ares underneath, which will make getting a solid mount more difficult. Good inspection and making the roof covering sound is good input.

 

Best,

Smitty

 

I followed your link and saw what BatteryPro did. I'm a halfway decent carpenter, but I don't trust myself to do that and be confident it's right. I would certainly trust someone who knows their way around an RV to do that for me though.

 

I found a link on that page to the 3M infommercial on the VHB everyone here has been talking about. That's some pretty impressive stuff. I can't apply it to my roof, but couldn't I apply that to the sides of my vehicle the way we were talking about? I could get some 10x10 aluminum squares, screw my anchor points to the squares, then tape the squares to the sides of the RV. Does that sound like it would work?

[MoonTimber]

I would make the roofing a fairly high priority as you don't want to have to undo whatever you put up permanently as mountings for your kayaks. On the windows, is there some sign of leaks there to make you suspicious? If so the best fix for most window leaks is to remove the window and replace the butyl caulk tape. You can find that at most RV supply stores or from Amazon.

 

I sat in the RV during a rainstorm for about twenty minutes three or four weeks ago and couldn't see any leaks, but a day later I noticed a light "rain trail" on the paint running from the edge of two windows that almost went down to the floor. It was barely visible, but there was enough to make me think the seals aren't doing their job. I figured I would have to pop the windows out or buy some kind of caulk. That tape is very inexpensive and the end result would look a lot better than blobs of caulk, so if I can figure out how to pop out the windows I will to follow your advice on this. The roof is another matter. I'll talk about that while responding to Stanley's post.

[wa_desert_rat]

I had thought that you had mentioned that your rooftop was fiberglass and that was why I mentioned VHB tape. It will not work on other roof types; and that roof type looks pretty nasty.

 

On the bright side, VHB tape *will* work on fiberglass that's well bonded. If the sides of your RV are fiberglass then that still might be an option.

 

Oh... and a leaky roof seldom shows itself by drops directly inside. A leaky roof allows water in and then the water simply follows the least resistance path; often pooling up in spots until it leaks out of that. And 'that" could be quite a way from the actual rooftop leak.

 

WDR

[MoonTimber]

Looking at that roof I'd peel it off and put down a new rubber sheet. Not fun or cheap but far more fun and cheaper than dealing with mold and rot in your walls or floor from a leak.

 

While you have it off you could get a better idea of what you have to mount your stuff to.

 

There is some damage to the roof from an old or current leak. There is a soft spot in the ceiling that's about 9 inches wide by 18 inches long. Everything else feels solid. So you are right, the proper thing to do is tear up the entire roof, inspect and repair.

 

The thing is, this is an RV we paid $4500 for. It's not the one we really wanted, it's the one we could afford. We were hit between the eyes after I got it home and had my mechanic go through it with a fine tooth comb. I need to spend about $1200 in mechanical repairs and another $800 in tires before we can go anywhere. We want to spend another $500 on the interior. Maybe I'm wrong but I think that after we put time and money into repairs we'll be fortunate if we can sell it for $6000. Our plan was to use it for one year and sell it. Then we would take our next tax return and a little bit of savings to look for another RV between 10,000 and $14,000. Hopefully, for $10,000 we could find something configured the way we really want it that doesn't need a bunch of mechanical and structural repairs. A year from now we'll have learned a lot of lessons about what features are important to us as a family, what to look for in an RV, and what to avoid at all costs.

 

I know you're right about the roof. There's probably a lot of things you could teach me to fix. I certainly don't want the roof leaking and getting worse than it is. But there is a limit to how much work I can put into this thing. I want to buy some more goop, or whatever the least expensive method is for patching leaks, and spend a day covering up anything that looks like a potential leak.

 

I like the kayak foam pads and the removable racks because those parts can be easily moved to our next RV. I will not see a return on any anchor points I install but that's the price I need to pay so that my kayaks don't blow away on the road.

[MoonTimber]

I had thought that you had mentioned that your rooftop was fiberglass and that was why I mentioned VHB tape. It will not work on other roof types; and that roof type looks pretty nasty.

 

On the bright side, VHB tape *will* work on fiberglass that's well bonded. If the sides of your RV are fiberglass then that still might be an option.

 

Oh... and a leaky roof seldom shows itself by drops directly inside. A leaky roof allows water in and then the water simply follows the least resistance path; often pooling up in spots until it leaks out of that. And 'that" could be quite a way from the actual rooftop leak.

 

WDR

 

I had to go find a photo of the side of our clunker. I couldn't remember what it looked like! I'm pretty sure this is not fiberglass. It reminds me of vinyl siding. I don't know if I can use that tape with these ridges involved:

 

[wa_desert_rat]

It doesn't take much tape. Buy a roll (Amazon sells it) and clean up a spot and test it. If it works then you're good. If not, then you're out about $25. Those "ridges" are not an issue; in fact if the tape adheres well to that siding then the ridges would reduce the angle from 180-degrees to maybe 150-degrees.

 

I wonder how many cans of that spray-on white sealant that guy on TV uses to make a boat with a screen-door bottom float will cover your rooftop. I used the stuff on a shed and it's been on there for a long time and no leaks (any more).

 

WDR

[Kirk W]

That corrugated siding could be either fiberglass or aluminum. But either way it probably isn't sufficient to attach much to, other than at locations where there is some sort of structural member. The siding looks to be in sheets, 2' or so wide and the length of the RV. The fiberglass that is flat laminated into the walls common today would probably hold using the plates double stick taped to the sides but with that you could possible pull it loose from the sides if you put too much tension on the tie-downs. I would not do that.

 

Looking at your windows, I'm sure that you will find that there is a frame on the inside that is removable. Once that is off you need someone inside to push the window loose from the existing tape and someone outside to prevent the window from falling to the ground. It isn't difficult but is a two person job.

[MoonTimber]

That corrugated siding could be either fiberglass or aluminum . . .

 

. . . Looking at your windows, I'm sure that you will find that there is a frame on the inside that is removable. . .

 

I went out and had a closer look. I'd say it's probably fiberglass. It looks like it's in sheets that are roughly four foot wide running front to back. It feels really solid, but I don't know if it's safe to use the tape on. I might call Fleetwood this week and see if anyone there remembers how this was built and whether or not I should use that tape or just bolt things on. Now that I've had a close look at the side I'm inclined to think I can just put some screws in there and seal them up with something rubbery.

 

I'll take a closer look at the windows this weekend. If it's not obvious I'll take a picture and post it.

[MoonTimber]

. . . I wonder how many cans of that spray-on white sealant that guy on TV uses to make a boat with a screen-door bottom float will cover your rooftop. I used the stuff on a shed and it's been on there for a long time and no leaks (any more).

 

WDR

 

I don't watch very much TV. What stuff are you talking about? Is it something I should try on the roof?

 

Perhaps I should start another thread on the cheapest way to seal my roof? I have at least three weeks of other repairs to work on first, but it helps to get an early start on suggestions. Especially since I am in the dark about what's currently available. I want to figure out the least labor intensive way to seal the roof that I can afford.

[skp51443]

On the roof, at least get a couple tubes of Dichor sealant and plug up anything that looks iffy.

 

http://www.dicor.com/

 

Maybe another whole approach to mounting the boats. Give up on a roof or sidewall mount and instead get a couple heavy duty cargo straps and circle the whole trailer and boats. That is going to secure them without fail and hopefully you can get two of them on and still open the entry door. Putting them on or off should be easy enough if you just toss the buckle over the top and leave it at a reachable height on the side of the trailer.

[MoonTimber]

On the roof, at least get a couple tubes of Dichor sealant and plug up anything that looks iffy.

 

http://www.dicor.com/

 

Maybe another whole approach to mounting the boats. Give up on a roof or sidewall mount and instead get a couple heavy duty cargo straps and circle the whole trailer and boats. That is going to secure them without fail and hopefully you can get two of them on and still open the entry door. Putting them on or off should be easy enough if you just toss the buckle over the top and leave it at a reachable height on the side of the trailer.

 

Woah, they have a lot of products! Which one were you recommending?

 

And do you mean go around the RV by running the straps under the chassis? Won't I get caught up on the chassis drive shaft?

[wa_desert_rat]

The only way to find out if VHB tape works is to try it yourself. Get some, put something on the sides of your RV with it, and after a few days see if it comes off easily.

 

WDR

[MoonTimber]

The only way to find out if VHB tape works is to try it yourself. Get some, put something on the sides of your RV with it, and after a few days see if it comes off easily.

 

WDR

 

The only problem is that the tape could pull the siding off. I don't know how they mounted the siding, so if I apply tape then add live weight, it's possible it could rip the siding away from whatever is behind it. It feels solid, so my guess is you're right and it'll work, but I'll try and call Fleetwood first.

[Pat & Pete]

I still think a trailer is a much better idea , but ...

[MoonTimber]

I still think a trailer is a much better idea , but ...

 

 

Hahaha! Maybe with our next camper!

 

I called Fleetwood. That wavy stuff on the sides of the camper IS fiberglass, and it's glued down firmly enough that they are confident it won't get pulled off. I told him I wanted to us the 3M sticky tape (I couldn't remember what VHB was called) to fasten some mounting points to the sides, so I can strap my kayak to the top. He said it should be just fine. But then I called 3M to see how small a piece of VHB I could use.

 

I got transferred around a few times and had to wait a total of twenty minutes on hold, but eventually they passed me to a woman who seemed to really know the product. She said it really wasn't a good idea to use VHB this way. If I understood her, a 4 inch square will only hold 1 pound of shear. She said if I had a bunch of 10 x 10 squares on the sides for mounting points it might work, but that it would be really tough to calculate it with any confidence because the force would be applied in a direction that the tape wasn't intended for -- it would be pulling out and to the side at the same time. Apparently it's designed to hold in a straight line perpendicular to the surface. I think that's what she meant by shear. She gave me the number to the automotive adhesive division which was closed for the day. She felt confident they would have a two part epoxy that would do exactly what I wanted without needing the 10X10 sheet. I could just glue the anchor points to the side of the RV.

 

I'll give them a call tomorow, but now that I know the sides are fiberglass glued to the wood behind them, I'm less afraid of using small toggle bolts and some sealant to mount inexpensive anchors points to the sides. In theory I could drill into the space behind a cabinet and put a washer and nut in there. I think if I make a serious effort to keep it clean looking it won't hurt me when I go to sell it, and it won't leak while I own it.

[Kirk W]

 

Apparently it's designed to hold in a straight line perpendicular to the surface. I think that's what she meant by shear.

That is exactly right. Shear is a side movement which could break the material that the tape is made of even without the sticky letting go on either side.