A Missing Screw Was Causing This North St. Paul School Roof Leak

Sometimes the culprit behind a nasty ceiling leak is something surprisingly small. We got called out to a school in North St. Paul, MN to track down a flat roof leak - and what we found was a single missing screw in the skylight framing assembly.

Here's what makes this tricky. When the entry point for water sits higher than where the TPO membrane terminates, water doesn't just drip straight down. It travels. It follows the path of least resistance through the assembly, and by the time it shows up inside as a ceiling stain, it can look like the problem is coming from somewhere completely different. That throws a lot of people off.

We've seen this scenario play out on commercial flat roofs more times than we can count - especially on school buildings with skylights. The skylight curb flashing and metal trim components have to be fully fastened and properly integrated with the TPO membrane below. One gap, one missing fastener, and you've got a water entry point that gets worse every time it rains.

The reason we point this out isn't to make a simple fix sound complicated. It's actually the opposite - we want building managers and facility teams to understand that small roof issues don't stay small. A missing screw today can mean saturated insulation, damaged decking, and interior finishes that need full replacement if it's left alone long enough.

We work with schools and commercial properties across the North St. Paul area on exactly this kind of repair work - TPO flat roofs, skylight details, flashing, you name it. Getting eyes on the roof early almost always saves significant money down the road.