Luan Buckling Underneath Roof Membrane...

[Leaf-Peeper]

There is an area near the side of our roof where the luan plywood is buckling/delaminating just underneath the roofing membrane (it's buckling is pushing upward underneath the membrane). I assume there is a leak that is causing this to happen. There are no signs of water leaking inside the trailer. I'd like to find where the leak is before I perform surgery to repair or replace the damaged area, but I can't find it. I've even done a pressure test with soapy bubbles using a leaf-blower, but still can't find it. On a side note, Eternabond had already been used over most of the roof already and will be used again to seal up the repaired area.

Anyone have any ideas on how to locate the source of this leak?

[martipr]

Almot wrote:
Can't help with locating the leak, but I am puzzled. Luan is not a common material on a trailer roof. Usually it's a particle board covered with rubber-ish EPDM coat. When EPDM is bubbling and separating from the particle board, chances are it is not caused by leaks.

Not quite true, it is usually plywood covered with Luan covered with rubber. There may well be exceptions.

[Bleugoat]

Ted, I would be very interested to know if you find exposed screws under your A/C and if they have caused any leaks. I am subscribed to this topic or if you start a new thread I will try to catch it.

My roof is aluminum frame with foam sandwiched between Luan and is buckling over a large area (I neglected my leak too long) so I am looking at a similar repair to yours next spring.

Bill

[Leaf-Peeper]

Thanks for the responses...

dougrainer: It appears the upper layer(s) of the luan has delaminated from the ones below, creating some wrinkles or buckling effect that is pushing upward. I think the lower surface of the luan is probably still secured to the foam core below.

Bleugoat: We'll have to pull our AC unit and see if we have a similar situation like you experienced. We have a new AC roof gasket is on order. I like your repair..., nice idea building up a raised curbing and spacers.

Almot: With the inside AC grill removed, I can see it's definitely a multi-layered, 1/4" luan product. I think is/was typical of an ultra-light built unit, constructed similar to the way the floors and walls are built.

[Almot]

Can't help with locating the leak, but I am puzzled. Luan is not a common material on a trailer roof. Usually it's a particle board covered with rubber-ish EPDM coat. When EPDM is bubbling and separating from the particle board, chances are it is not caused by leaks.

[Bleugoat]

Your problem may be different than mine described in this post:

Roof Repair

Hope it helps.

Bill

[dougrainer]

It is rare(I have never seen it) for water damaged Luan to actually put upward pressure on the membrane. I HAVE seen incorrectly secured Luan (staples too short or no mount hardware at the area) that has lifted up. If water damaged, the luan has NO strength at all to do anything. I will bet you just need to peel the rubber back and secure the Luan. Doug