Project Notes
Over two decades of roofing work teaches you things you can't read in a catalog. Not every failure is obvious, and some of the most instructive failures take years to announce themselves. You finish a job, the owner is satisfied, the inspections pass — and then ten winters in, a pattern appears that tells you something about your choice that the first-year performance never hinted at. These notes come from that experience: projects where materials behaved exactly as expected, installations where a single decision still looks right from the ground, and a few choices we'd unhesitatingly redo if we had the chance. They're not gospel. They're the kind of ground truth a contractor or serious DIYer might actually find useful before committing weeks of work and five figures to their own roof.
The best education in roofing doesn't come from manufacturers' spec sheets. It comes from talking to the roofer who repaired the job another roofer botched, from standing in an attic with fresh water damage and a structural engineer explaining what went wrong, and from watching how different materials and installation approaches perform over actual seasons. We've learned as much from failures we fixed as from the jobs that stayed dry. A roof that lasts thirty years teaches you less than one that failed in year five — because a failure narrows down the problem. When nothing goes wrong, you never know which of your choices actually mattered.
The evidence, laid out
Drip edge and metal flashing failures almost never stem from fastener failure or material degradation the way homeowners often assume. They stem from one source: water that should move away from the structure gets trapped instead. We've pulled off roofing where the fasteners held perfectly sound, where the shingles showed no deterioration, but where the underlayment had become a pond. The fix isn't arcane — it's always about slope, overlap, and crucially, making sure water can reach open air without pooling at a corner or getting held under a lip. One project that shaped how we think about this was a 1970s addition where the original builders had run the roof edge parallel to the ground instead of sloping it toward a gutter. The main roof had slope, but the last six inches leading to the addition's gable didn't know where to go. Water would reach the edge and sit there, finding its way under flashings that were perfectly installed otherwise. We added a return lip and the problem dissolved. It sounds trivial until you're standing in an attic with fresh water damage, looking at a contractor's explanation that amounts to "sometimes roofs leak."
That experience repeated itself across different projects with different materials. The constant was always the path water takes. A 2003 metal roof we installed with a standing seam and proper purlin returns has never leaked despite a valley that concentrates water from two directions. A 1998 comp shingle roof we fixed by addressing slope but not installing proper cricket flashing behind a chimney started leaking again five years later because we'd only solved half the puzzle. These aren't random outcomes. They're consequences of whether the water's exit strategy was clear.
The takeaway
Your roofing materials — drip edge gauge, metal coating, flashing profile, fastener type — are only as good as the path you give water to take. They're not the first line of defense. The first line is making sure water reaches open air instead of pooling or getting trapped. Drip edge, gutter slope, flashing returns, cricket systems — they exist to answer one question: where does this water go next? If you answer that clearly before you start, ninety percent of the problems people call roofers about become preventable. The metal itself matters, but it matters second. You can buy premium gauge and premium coating and still watch a roof fail if the water's exit strategy was unclear. We look at every building addition and odd roof corner the way we looked at that 1970s addition: with an eye toward where water wants to go and what we need to build to ensure it goes toward the gutter instead of into the walls. That perspective has outlasted every material choice we've made.