Tillamook sits in a broad valley at the head of Tillamook Bay, where five rivers — the Wilson, Trask, Tillamook, Kilchis, and Miami — converge before emptying into the Pacific. This geography creates one of the wettest locations in Oregon, with annual rainfall regularly exceeding 90 inches. The surrounding Coast Range mountains force marine air upward, wringing out moisture as orographic rain that falls on the valley floor and everything on it.
For roofs, this means water — relentless, persistent, gravity-defying water driven by wind from every direction. The flat valley floor also traps moisture and fog, creating conditions where roofs can stay wet for weeks during the rainy season. Moss growth is aggressive, gutters overflow constantly, and any weakness in flashing, valleys, or underlayment gets exploited quickly. The Tillamook Creamery building itself is a testament to the challenge — massive, industrial-grade roofing designed to handle conditions that break lesser systems.
From the residential neighborhoods around Tillamook High School to the farms along Long Prairie Road, from the commercial strip along Highway 101 to the homes on the hillsides above town — Tillamook roofs need to be built for water, first and foremost. Everything else is secondary.
