Roofer used zinc-coated screws instead of stainless on metal roof
Using zinc-coated carbon steel screws instead of stainless steel on aluminum PVDF-coated panels creates a severe risk of galvanic corrosion that can cause premature panel attachment failure and void the roof warranty. Homeowners are left dealing with widespread installation defects, including over-torqued, under-torqued, and crooked fasteners across the majority of the roof.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Relying on the fact that clips or fasteners are not exposed to the elements.
- 2Waiting to see if an inspector certifying the watertight warranty raises the issue.
- 3Comparing fasteners to manufacturer recommendations and hoping for the best
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“These were only a representative "handful" of the installed screws/fasteners - a majority were like this.”source ↗
“Look overtightened.”source ↗
“A refreshingly delightful mix of over and under torqued with a sprinkling of sideways. Not good”source ↗
“Roofer used zinc coated carbon steel instead of stainless screws on aluminum pvdf coated panels. I realize this voids the warranty, but considering this is a snap lock metal roof, do I need to worry about failure of the panel attachment?”source ↗
“Just found out this info this morning, very frustrating.”source ↗
Where this came up
People with this problem also raised
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