Holes in Unvented Metal Roof
Posted this on FHB, but thought I might as well here as well. We are doing a 2nd story addition + finished attic with a standing seam metal roof (White galvalume preformed sheets). Open cell foam is to be sprayed between the roof rafters for insulation. Located in Va. Roofers left 12 3×4 inch holes at the ridge truss juncture to tie their safety harnesses. Holes were made with a hammer and went through the OSB and underlayment. In some cases metal was bent into the hole. In others, they were covered with metal sheet. Due to COVID, inspections are being done via camera phone. Inspection passed. I don’t think the inspectors saw this. Some of the flashing is questionable as well.
Contractor has said the following:
1) Don’t worry. They under the ridge cover. Cover appears to be 3-4 in on each side so it’s close.
2) Will patch with metal below ridge cover and Bondo and wood below before foam.
3) It “passed inspection”.
To go back to square one would involve removing the roof, replacing the sheathing and underlayment and reroofing which is an expensive proposition and time consuming.
My main concern is:
1. Will this patch work?
2. Will it last for the life of the roof? It will be between foam and metal.
3. Will open cell foam be ok?
Pictures show holes before any patch(2)
After metal only patch and pre-Bondo + wood (2).
Sidewall flashing juncture for different roof levels. Board is Hardy Plank.
Contractor wants to patch and foam now. I’ve not agreed pending verdict on holes patches. I’m calling in roofers to get some additional opinions but it’s a slow process given how busy they are these days and this type of roof is now common.
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That is incredibly sad but not surprising given your contractor's response.
Ugh, another casualty of the "Git 'er done!" mentality. It didn't need to be done that way, but the crew was more concerned with speed and getting out of there than anything else.
There are two issues.
The first is why the crew thought they needed to cut any holes in the sheathing to anchor their safety harness. All the crews I work with, and my own fall protection, is attached through the sheathing into solid framing below by several screws. What they did was just bush-league.
The second is how important the holes are. That depends on how the ridge is detailed. If they are above the closure strips, or bent-up ends of the roofing panels, I wouldn't worry. If they aren't then something more than cramming bits of flashing onto them needs doing - and if your contractor can't come up with anything better, then yes, he needs to redo that section of roof.
Thanks for your reply.
+1 for redoing that section of the roof. I would likely make them replace the trashed sheet of OSB where the hole is. Weak spots in a roof like that are a recipe for disaster when the next contractor unknowingly steps in the weak spot.
Don't except "it passed inspection" as an answer here. The contractor might have been crossing his fingers the inspector would miss that hole, than thought "YAY!" when the inspector missed it. Inspectors often don't find everything, and there are many horror stories out there of catastrophes (in some cases people have died when things collapsed) that could have been prevented by a proper inspection.
Your issue is unlikely to cause a major safety problem, but it's very amateurish and a hasty patch job of a "repair". I wouldn't except that with new construction.
Thanks for your reply.