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Topic: roof crack with picture (Read 724 times) previous topic - next topic

roof crack with picture

good morning all,

this is a crack on the roof that i ground down today to see how bad it is.
I have a roof coating that was applied by FOT back in 2013 if i remember correctly. I used a dremel with a round tip to work my way down.
I could not tell when i was past the roof coating or gel coat until i got to this gray part which i don't know what it is.
the crack is still visible in the gray part which is about 1" long. the total length of the crack is about 1 foot.

what section of the roof have a reached?
Do not want to continue working my way down into something I'm making worse. i was hoping it would not be so deep
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: roof crack with picture

Reply #1 –
It's hard to tell without touching/seeing. Don't cut a V into the crack, that will only localize stress more in the crack. To repair the crack must be removed and I generally stay at about 12-1 ratio. 12 wide 1 deep. Yes it ends up getting big quick. West marine and filler to repair. Can be applied with bidirectional cloth. Epoxy has hi adhesion rate compared to polyester vinyl resin and zero shrinkage. Until the crack is removed it still exists and stands to recrack in same position. Bridging over may be a permanent repair but is not aesthetically acceptable most places. Would be fine on my roof.
Scott

Re: roof crack with picture

Reply #2 –
Coating
Gel Coat
Fiberglass
Plywood

It looks like you are into the fiberglass. Look to see if the crack has been completely ground out. If you hit the plywood it is not a problem. As Scott indicated, if you go down 1/8 inch deep you should be roughly an inch and 1/2 wide. On my own cracks, I've used epoxy mixed with powdered filler and chopped strand mat on individual cracks. I may ultimately put a layer of fiberglass cloth over the entire top.

I would also look to see if there is some source of water that caused the crack. The source can be several feet away at one of the A/Cs or other roof penetrations. The water can migrate several feet either between the fiberglass and the plywood or even between the gel coat and the fiberglass, ultimately surfacing in a crack. I'm sure cracks may form from other causes as well. If you've only got a single crack, it's pretty minor to fix.
Bruce & Linda
2004 U295, Build # 6268, ISL400 CAPS
2016 Ford Explorer Sport or 1985 Jeep CJ7

Re: roof crack with picture

Reply #3 –
Frank, another possiblity for you is this:
Waterproof Plastic Repair Kits Fixes cracked ABS PVC Acrylic Wood More
This stuff is amazing.  I used it on my roof to patch some holes left from a Sat. Dish that was removed. It adheres to the fiberglass and has great strength in bonding the cracks.  It may be worth taking a look at.  Without color additives, it is an off white color, but you can get the color kit and color match if needed.
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: roof crack with picture

Reply #4 –
I believe I'd strongly consider using the plast aid, (preferred),or alternatively Marine Tex epoxy to repair the crack without much further grinding.  Keep an eye on it occasionally thereafter.  If it comes down to it then a reinforced patch with lots of grrinding, scarfing back might be required as others have recommended.  Wouldnt jump right into this unless you have some 'glass experience. Try simple first.
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: roof crack with picture

Reply #5 –
I think you have already received some good advice but if you wish to put your mind at ease, put in a call to Extreme in Nac and get their advice..... Might sleep better.
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Lynn & Marilyn Sickel
Tollville, AR
1997  U320  40'
2021 Chevrolet Silverado pickup
Motorcader  17257

Re: roof crack with picture

Reply #6 –
Thanks everyone
I'll be in Nac in a week or two. I'll see whether they say
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH
 

Re: roof crack with picture

Reply #7 –
I have a couple of those.  I have the same armorcoat coating.  The crack is (at least on mine) emanating from the fiberglass through the armorcoat.  The armorcoat ironically isn't all that strong and it's more like a paint.  On mine I cleaned it with acetone and put a fat bead of polyurethane sealant over it and it never expanded or got worse.  Wise advice to all would be to (gently) pressure wash your roofs and then get down on your hands and knees and inspect them front to back.  We had fairly horrible cracking where the anti-slip strips were at the ladder and that was fixed by the dealer we bought our motorhome from with 3m 5200.  Let me tell you - that isn't going *anywhere*.