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.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
Roofer used zinc-coated screws instead of stainless on metal roof
- 1Relying on the fact that clips or fasteners are not exposed to the elements.Did this help you?
- 2Waiting to see if an inspector certifying the watertight warranty raises the issue.Did this help you?
- 3Comparing fasteners to manufacturer recommendations and hoping for the bestDid this help you?
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
- 7How to fix loose metal roof trim that won't stay in
- 54How to tell if roof flashing is installed wrong
- 2How to fix a large hole in metal siding
- 2Can you install metal roofing over an uneven or messed up roof?
- 2Where to buy DIY metal roofing materials and matching parts
- 4Why does my metal roof keep leaking around the screws?