water collecting on high top causing leaks

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decodancer

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rooftop.jpginterior roof.jpg My high top ford used to be an ice cream truck. My guess is it also had a roof air installed at some point. There is an indent of about 3/4 inch where the ac used to be and where the roof vent is now. Every time it rains, water collects in the area and leaks in through the vent. I've tried everything to seal it but it still drips. When I move the van a wall of water runs down the windshield. If I forget that it rained and roll my drivers side window down I get soaked. I tried building an interior wall to see if I could push the indent up but it didn't work. I thought I might take the vent out and fiberglass over the 14x14 hole or could install a larger escape hatch. I thought maybe a larger vent might help but it might make it worse. Do any of you have any ideas? I left my clean laundry in the van the other day and snow melt from the roof soaked everything. I added pictures, the vent is broken from a mechanic who was sure the van would fit but it leaked before it was broken .
 

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I don't know if this is the CORRECT way to deal with it or not, but this is what I'D probably try . . .

Remove the roof vent. THOROUGHLY clean that area of the roof. Not just soap and water, use something that will remove every trace of car wax. Maybe acetone. Talk to somebody at a store that sells automotive paint and body supplies for a recommendation.

Lay a straightedge across from side to side and measure to see how much the roof is depressed. Build a square wooden frame to raise the vent the necessary amount. I believe the standard opening for roof vents is 14 x 14 inches, (check your current hole) so you'll want the inside of your frame to be 14 x 14. The outside will of course be bigger, so you'll have to enlarge the hole slightly to accommodate the outside of the frame.

Attach the new frame solidly to the roof so it sticks up far enough to be slightly above the straightedge.

Using thin coats, fill in the depression around the frame with Bondo or other auto body filler - again, check with the supply house to get something ok to use over fiberglass - untile eliminated any low spot where water can pool.

Attach the roof vent solidly to the new wooden frame.

Good luck

Regards
John
 
Greetings!

This is a very common problem with roof vents, makes me glad I don't have any in my current van. Instead I have sliders in the sides of the roof.

I've helped a lot of friends with this same problem, here's my solution:

a) Take out the current roof vent and discard.

b) Buy a new roof vent, make sure it includes the mounting kit. If not purchase the mounting kit separately.

c) Measure the OUTSIDE edges of your new vent.

d) Build yourself a flat window frame large enough to go from the side of the opening, to 3" wider than the outside of your new vent. At least 1/2" thick. If you can make them out of marine plywood, and make them a single piece. You will need 2 of them, one for the inside and one for the outside. Paint them with good oil based primer followed by gloss white oil based paint.

e) Pick up 2 sheets of closed cell foam gasket material the size of these frames, and 8 sets of carriage bolts, nuts, lock washers, and rubber washers, to bolt this frame together.

f) Place the gaskets between the top and your new frames, and clamp this whole assembly in place so you can drill holes for the bolts.

g) Mark a line one inch in all the way around your frame. This will be your bolt line, and it should not interfere with the installation of your new roof vent. Double check it just to make sure.

h) Drill your holes. One at each corner of your bolt line, and one midway between on each side.

i) Insert you bolts from the top side, using a rubber washer on the top side.

j) From the inside, install a lock washer and a nut onto each bolt. Now tighten them all up good and snug but not too forcefully because we don't want to crack the fiberglass top. It should be snug enough to totally flatten out the top though so the gaskets and rubber washers will make a good seal.

k) If your bolts inside are too long you can cut them off if desired.

l) You should now be ready to install your new vent as per their instructions, and it shouldn't leak for at least 5 years. If you ever discover a leak, simply replace the appropriate gasket.

Hope this helps...

The CamperVan_Man
 
Thanks guys! I never thought of building up the height where I attach the vent. Adding the piece inside will definitely give it more strength to bolt in. Is there any reason why I could not bolt in from the inside just because I like the look of a flat top instead of a nut showing. I may try building up the area around but worried about the weight and cost of that much Bondo. That may be the only way to keep it from running off the front though. Now if we could just get a sunny day with temps above freezing... Where did you find the sliding windows, I'd love to add those as well.
 
Instead of gasket material, I would use butyl sealing tape.
 
I've seen this problem before and wondered if rib/support were rotted.
Are you able to push the roof up from the inside by hand??

Having never dealt with it, I wonder about the possibility of creating some kind of new supports to push it back up.
I might even be inclined to make a few shaped ribs and actually bolt them thru the roof. To seal the bolted areas I'm thinking a roofing membrane and white roof coating.

If that won't work for you, try some (white) rubber roofing build-up material with the white roof coating. I did this on an RV that had a small area that puddled.

A build up with Bondo that large would get heavy and probably break loose with the flexing if the old ribs are shot.
 
decodancer said:
Thanks guys! I never thought of building up the height where I attach the vent. Adding the piece inside will definitely give it more strength to bolt in. Is there any reason why I could not bolt in from the inside just because I like the look of a flat top instead of a nut showing. I may try building up the area around but worried about the weight and cost of that much Bondo. That may be the only way to keep it from running off the front though. Now if we could just get a sunny day with temps above freezing... Where did you find the sliding windows, I'd love to add those as well.

Greetings!

You could put the bolts through in reverse fashion, but it makes it harder to seal, and if they ever need a little tightening, it would have to be done from the outside and probably in the rain.

Bondo doesn't really work well with fiberglass, you would basically have to do a re-fiberglass job, like repairing a boat, then re-gelcoat everything, and you're talking a major and very expensive job.

You want to be careful about trying to force the whole roof back into it's original position too. It might be brittle enough to crack and/or break, and then you've opened up a whole new can of worms.

I didn't go into it, but what I do is make an interior molding of coroplast (plastic cardboard), it's light weight, durable, and water proof. It will be made just like one of the plywood pieces, just slightly larger, so that the outer most edge will fit flush up against your ceiling, totally hiding the plywood and bolts. You make it out of multiple layers of coroplast. The first layer(s) the center whole will actually fit around the outside of the interior plywood, flush against the ceiling, This outer diameter will be the same size the new layers you will be adding will be.

Your next layers, will be basically the same design as the plywood, with the bolt holes. This will cover up the interior nuts and bolts. Your final layer will not have the bolt holes, so they will now be hidden.

Once this is all put together, you can either upholster it, or what I do is get some woodgrain self stick vinyl shelf paper, and cover it with that. I try to pick something that will look nice and lend itself to the existing interior.

Once completed, you can attach it to the plywood with finishing screws and finishing upholstery washers, and you will have a totally professional and gorgeous installation that nobody will ever know was a repair job.

I have done this on half a million dollar motorhomes, and nobody ever knew it was a repair job from either inside or outside.

Holler if my directions aren't clear enough.

My side windows came that way, I didn't install them.

Water pooling on the roofs happens a lot and is basically just something that we have to live with, because repairing it CORRECTLY would basically require redesigning and replacing the whole roof which would probably cost more than what most rigs are worth. So simply repairing the leaks is the most cost effective way to go.

To solve the problem of water coming into the cab, get you a pair of those plastic rain visors that attach to your doors. They will give you the added benefit of being able to leave your front windows cracked, even in the rain.

And always remember: If you're not a Happy Camper, it CAN be fixed!

Cheers!

The CamperVan_Man
 
Thanks again for all the good advise and detailed instructions. I can't wait to get started on this repair! The rain visors are a great idea too.
 
I have a magical solution that's called Henry's Roof patch #208. I've used it on every type of application and 100% of the time it has worked. I've put it on under 3 inches of standing water-- no more leak!! Here's a link to it on Amazon so you can see what it looks like, but buy a gallon of it at Home Depot.
http://www.amazon.com/Henry-HE208030-Patch-Repair-Cement/

It's like a heavy black tar but on a high top no one should be able to see it. If that is a problem they are now making a white version but I've never used it.
Bob
 
Lots of great advice on here.

Looks like there musta been a rooftop airconditioner on there originally, and the roof couldn't handle the weight, so this is structural damage.

I'm with B&U and think new roof supports are in order to redome the roof back up into it's original position. With a good dome to the roof, there's no where for the water to pool up, and therefore, no more leaks. Once built back up, I'd snow-coat it to reseal it.

It's not an intimidating project to me at all, but I build custom stuff for a living.
 
Patrick46 said:
Lots of great advice on here.

Looks like there musta been a rooftop airconditioner on there originally, and the roof couldn't handle the weight, so this is structural damage.

I'm with B&U and think new roof supports are in order to redome the roof back up into it's original position. With a good dome to the roof, there's no where for the water to pool up, and therefore, no more leaks. Once built back up, I'd snow-coat it to reseal it.

It's not an intimidating project to me at all, but I build custom stuff for a living.

Greetings!

There was a whole lot of inferior tops put out, that were typically less than 1/8" and frequently less than 1/16" in thickness. By now they are old and brittle, and trying to straighten those out back to original will usually cause them to either crack or break.

My guess is that it was one of these inferior ribless tops to start with...

Cheers!

The CamperVan_Man
 
I'm afraid that CamperVan_Man is right as it does not seem to be a good quality top compared to others I've had. I may put a truss or two across the interior just to prevent the problem from getting worse. It will give me something solid to attach my ceiling panels to. I've seen laminate wood flooring used to finish but I don't know about the weight factor. I'll probably stick to 1/4 inch thick paneling. I like the stuff that looks like wallpaper. Very girlie.
 
The CamperVan_Man said:
There was a whole lot of inferior tops put out, that were typically less than 1/8" and frequently less than 1/16" in thickness. By now they are old and brittle, and trying to straighten those out back to original will usually cause them to either crack or break.

If it cracks, then it's most certaintly a thin skinned model, in which case I'd put acouple more layers of fiberglass over the top of that...(after rebuilding the inner framework.)
...so that now it would have the proper dome to it, it'd have all new inner structure for strength and a nice new thicker skin...which in turn would seal it out for years to come.
If you'd ever wanna put solar panels up there, then now you'd have something ready to handle the load too.

but like I also said...this kinda job wouldn't intimidate me in the least. Heck...I'd be inclined to do something really custom to it once I had it apart! :D
 
Patrick46 said:
If it cracks, then it's most certaintly a thin skinned model, in which case I'd put acouple more layers of fiberglass over the top of that...(after rebuilding the inner framework.)
...so that now it would have the proper dome to it, it'd have all new inner structure for strength and a nice new thicker skin...which in turn would seal it out for years to come.
If you'd ever wanna put solar panels up there, then now you'd have something ready to handle the load too.

but like I also said...this kinda job wouldn't intimidate me in the least. Heck...I'd be inclined to do something really custom to it once I had it apart! :D

Greetings!

Through a lot of experience with these inferior tops, we have come to the conclusion that trying to re-fiberglass them etc. just isn't worth the time or effort since your base is faulty to start with.

Instead, we just tear them off and build an entirely new roof from foam insulation board sandwiched between coroplast on the inside and either coroplast or masonite on the outside. We build new aluminum ribs to give it superior strength. We leave these ribs exposed on the inside, they are inverted U shaped with holes in the legs. Leaving them exposed was my idea, because I figured that this would give lots of good places to hang clothes, lights, etc. and that function was more important than beauty in this case. Total cost is usually under $300.

If you go to make one of these, due to the materials used, the surfaces are all flat, however, if you make the back several inches lower than the front, the water will auto drain off the back.

We only do this if the tops are too far gone to salvage.

Cheers!

The CamperVan_Man


Greetings!

For those of you with pooling problems that you just can't live with...

Take a cotton rope, or probably any type of wicking material. Tape the center down at the lowest spots where the pooling occurs. Then run the ends of the rope over the sides and down far enough that it is at least 3 inches below the lowest spot on top. The longer the better though. For aesthetics you can enclose the wicks in molding or tubing etc. as long as it is not blocked from absorbing the water in the low spots. Natural capillary action will now drain those pools off with no energy or further work required.

We have actually ran rope nets over the entire roofs of a number of very expensive Allegro and Tiffen Motorhomes, because they had horrendous pooling and consequently leaking problems. You would think that on rigs costing upwards of half a million dollars they would have had the good sense to put slightly rounded roofs on them...

Anyway, that's a relatively cheap and easy, down and dirty, trick that can be implemented almost instantly if the need arises, with a little rope and duct tape. If you're out in the boondocks, and a roof vent starts leaking, run a square of rope around where the roof vent connects to the roof, then over the sides. Your leak should stop shortly thereafter and remain dry until proper repairs can be made.

Hope this helps...

Cheers!

The CamperVan_Man
 
I love the rope trick and will implement that tomorrow. Many of the other repairs are a bit beyond my capabilities though. I'm afraid of heights and just getting me on the roof is a challenge. I do have a great neighbor who is a handyman extraordinaire to help me with mounting the new vent once I build the frames. I don't think the roof is unsalvageable. It doesn't leak and seems solid except where the ac used to be. I often wonder if it was an owner install though. I had this annoying squeak that used to drive me batty when I got on the highway. I finally realized that the roof was coming loose at the front. A dozen self tapping screws and no more squeak.
 
decodancer said:
I love the rope trick and will implement that tomorrow. Many of the other repairs are a bit beyond my capabilities though. I'm afraid of heights and just getting me on the roof is a challenge. I do have a great neighbor who is a handyman extraordinaire to help me with mounting the new vent once I build the frames. I don't think the roof is unsalvageable. It doesn't leak and seems solid except where the ac used to be. I often wonder if it was an owner install though. I had this annoying squeak that used to drive me batty when I got on the highway. I finally realized that the roof was coming loose at the front. A dozen self tapping screws and no more squeak.

Greetings!

<b><u>DO NOT</u></b> under any circumstances let anybody get on top of that roof. Please use a ladder and do all of the work from the side just to be safe.

Cheers!

The CamperVan_Man


bindi&us said:
Damn, I had forgotten all about that trick.

Greetings!

It always amuses me just a little bit when good old fashioned boondock survival techniques can crash head on to solve the problems of very expensive rigs that wouldn't be caught dead in anything less than a first class resort... hehe...

Cheers!

The CamperVan_Man
 
Just a quick update. One of the seasonals has a new vent that I can have. It was taken off of his new rv and replaced with a fantastic fan. I need to wait till next week but money is so tight, it's worth the wait. It's been raining nonstop for three days now. I used one of my plastic storage drawers to catch water under the vent and it was filled to the brim and overflowing overnight. I had to use a bucket to empty it enough to lift. Last night I got a Max Air vent cover from the camp store for $16 with my discount and just sat it over the vent. I plan on screwing it down once I get the new vent. I checked this morning and the drawer had only about one inch of water in it. Quite an improvement.
 
Greetings!

I'm a huge fan of those vent covers, they do add height, but it's sure nice to be able to leave your vent open without having to worry about rain, or while driving.

Cheers!

The CamperVan_Man
 
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