94 Toyota Seabreeze, Aluminum roof.Have a tiny leak on the sidewall in the bed area over the cab. A bit of time spent with a friend, soap and water solution and a leaf blower isolates it to the roof seam under the extruded aluminum trim.I do not see an issue fixing the leak, but noticed that the roof seam (where the front aluminum and the aluminum roof meet) is free floating and not attached to the frame. There is a good 3/8" of give in the seam area, but not at the edge. There is no evidence of water damage inside under the seam, so unlikely caused by rot. So should this seam be free floating or attached?I was going to use tape to seal this seam but am now thinking a lap sealant like Dicor would be better, any thoughts on that?Any input, thoughts, ideas, suggestions, opinions or wisecracks greatly appreciated. Jim

I would use the Dicor self leveling lap sealant right on the line, let it dry, and then apply 4 or 6 inch wide Eternabond tape. This should give you a long lasting, non leaking seal.This thread belongs in the Tech Issues forum rather than in the DIY forum so I will move it there.Barney

BarneyS wrote:I would use the Dicor self leveling lap sealant right on the line, let it dry, and then apply 4 or 6 inch wide Eternabond tape. This should give you a long lasting, non leaking seal.This thread belongs in the Tech Issues forum rather than in the DIY forum so I will move it there.BarneyExactly what I was thinking that I would do. Double seal it against future problems.

Does not seem very technical and I am going to Do It Myself. But Thanks : ) Jim

agesilaus wrote:BarneyS wrote:I would use the Dicor self leveling lap sealant right on the line, let it dry, and then apply 4 or 6 inch wide Eternabond tape. This should give you a long lasting, non leaking seal.This thread belongs in the Tech Issues forum rather than in the DIY forum so I will move it there.BarneyExactly what I was thinking that I would do. Double seal it against future problems.X2. Eternabond will take care of your problem. The Dicor is extra protection.

I used conventional tube sealant on my aluminum roof and still had a tiny leak. I covered everything with Eternabond, including the seams and no more leaks. You don't need 4"-6" of tape to seal seams or other. IIRC, I cut the tape down to 1" for the standing seams. A front or back cap seam deserves the full 4".Get everything surgical clean before applying the tapes. That means no silicone residue whatsoever.

Roof seam and leak | Good Sam Community

jjrbus
Explorer
Jan 23, 2016
Thanks for the response. But what kind of caulk did the manufacturer use? Jim
westend
Explorer
Jan 23, 2016
The aluminum roof on my trailer is free floating, no fasteners in it except for the vents.
jjrbus
Explorer
Jan 22, 2016
Thanks for all the input. Having a thought on the seam. There are no visible fasteners. The edge of the roof is rolled over the siding, so roof and front piece likely put on as one. Not one piece installed, fastened than second piece installed.

If I fasten along seam might cause a depression allowing water to pool.

Other than vents and such there are no visible fasteners on roof. I have not found another to look at so am going to leave it the way it is. Don't seem right?

Ordered some Dicor self leveling sealant and butyl putty today from Amazon for seam and to redo extruded trim.

The caulk appears to be OE which is 22 years old and in great condition. What is that stuff? I'd like to get another 22 years on one application!

Jim
Gjac
Explorer III
Jan 22, 2016
jjrbus wrote:
This is the front seam, it is not a cap, more of a joint, looks like a grooved lock seam.

OK, surgically clean, Check. Coat with Dicor, Check. Cover Dicor with Eternabond, Check.

How about the seam is not secured to the frame? Just does not seem right. Jim
I think I would drill a few small holes in the Al next to the gap then insert a stiff piece of wire and see if you can feel a frame member underneath. You may have to angle the wire to reach the frame. If you find the frame the wire will give you the length of the screws you need. I would drill and screw every 6 -12 ins along the seam on an angle and see if you can close the gap. Then caulk and cover with the tape. Good luck with your repair.
RVcircus
Explorer II
Jan 20, 2016
+1 on the Eternabond. I'd also consider resealing that side trim while you're at it.

I'm not sure about the free floating roof and agree it doesn't seem right, but it doesn't look to have any fasteners. I'll have to plead ignorant on that one.
jjrbus
Explorer
Jan 20, 2016
This is the front seam, it is not a cap, more of a joint, looks like a grooved lock seam.

OK, surgically clean, Check. Coat with Dicor, Check. Cover Dicor with Eternabond, Check.

How about the seam is not secured to the frame? Just does not seem right. Jim
BarneyS
Explorer III
Jan 19, 2016
It will bond just fine to the Dicor sealant. I, and many others here have done just that with no problems. Mine is going on 9 years and still holding just fine. :)
Barney
Cloud_Dancer
Explorer II
Jan 19, 2016
Call Eternabond, ask them if their tape will bond to Dicor. If it doesn't, you'll have a bigger mess.
BarneyS
Explorer III
Jan 19, 2016
westend wrote:
Snip... You don't need 4"-6" of tape to seal seams or other. IIRC, I cut the tape down to 1" for the standing seams. A front or back cap seam deserves the full 4".

Get everything surgical clean before applying the tapes. That means no silicone residue whatsoever.

I believe he was talking about the front cap/roof intersection of his camper - hence my recommendation of 4" or 6" Eternabond.
westend
Explorer
Jan 19, 2016
I used conventional tube sealant on my aluminum roof and still had a tiny leak. I covered everything with Eternabond, including the seams and no more leaks. You don't need 4"-6" of tape to seal seams or other. IIRC, I cut the tape down to 1" for the standing seams. A front or back cap seam deserves the full 4".

Get everything surgical clean before applying the tapes. That means no silicone residue whatsoever.

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