Coast guide · Oregon Coast
Metal roofs on the Oregon Coast
An aluminum roof is the best fit for most Oregon Coast homes: it has no iron for salt air to rust, and Interlock® panels lock on all four sides against winter storms. Here is how the material, the wind figures and the warranty work at the coast, and where we have already installed.
150 completed Interlock® roofs in coast towns in our Job Book, since 1998.
What does salt air do to a roof?
Salt air speeds up corrosion on any roof that relies on a coating to protect iron. On the coast, wind carries salt spray inland and leaves a film on every roof surface, and the damp months keep that film wet. On a steel roof, the cut edges, scratches and fastener holes are where rust starts. Asphalt shingles lose granules to wind and rain, and cedar grows moss and needs regular treatment in the marine humidity. So pick the material for the salt and the weather first, then choose the look.
Why is aluminum the material answer at the coast?
Aluminum has no iron in it, so there is nothing for salt air to rust. It forms its own thin oxide layer that protects the metal. What does corrode aluminum near salt water is contact with a different metal, so the details matter as much as the panels. ICC-ES ESR-1790 specifies aluminum ring-shank nails for the aluminum shingle and shake panels and stainless steel screws for the tile, all supplied by the manufacturer with the system's own trims, and the Guardian warranty excludes damage from dissimilar metals and dissimilar metal fasteners. The finish is the Alunar® coating, a 70% PVDF system designed and tested to meet AAMA 2605 and warranted for 30 years.
How does an interlocking roof handle coast storms?
Every Interlock® panel locks to its neighbors on all four sides and the fasteners are concealed, so wind has no free edge to lift and no exposed screw head to work loose. The manufacturer warrants the panels to resist winds of up to 120 mph when installed to manufacturer specification, and ICC-ES ESR-1790 lists allowable uplift loads of up to 177.5 psf for the shingle panels (Slate and Cedar Shingle patterns). Coast jobs are scheduled around the winter storm season, and we do not leave a roof open with weather coming in.
Which Interlock profile suits a coast house?
Match the profile to the house. Cedar Shingle and Shake keep the weathered-shingle look of a Cannon Beach or Manzanita cottage without the moss and splitting of real cedar. Slate suits the older two-story homes in Astoria, and Standing Seam suits a modern beach house with long, simple roof planes. If your home is in a historic district, check with your local historic landmarks commission before you choose a profile and color; we bring samples to the roof consultation so you can see them against your siding in coastal light.
What about rain and moss on the coast?
The coast is the wettest part of Oregon we roof, and moss is the result on asphalt and cedar. Moss needs something to root in: the granules of an asphalt shingle or the fibers of a cedar shake. A smooth, coated aluminum panel gives it far less to hold, and rain rinses the surface. Keep gutters and valleys clear of needles and debris, which is ordinary care for any roof.
Is the warranty valid near salt water?
The Guardian Lifetime Limited Material Warranty applies on the coast on the same terms as inland, and its certificate has no clause about distance from salt water. It covers the original purchaser for as long as they own the home and transfers once; the second owner is covered to 50 years from substantial completion, and the Alunar® coating is warranted for 30 years. Read the exclusions before you sign: the coating warranty excludes corrosive, aggressive or industrial atmospheres such as those contaminated with acidic or chemical fumes, and the material warranty excludes dissimilar metals and ice damming, among others. Read the Guardian certificate (PDF).
Where we have installed on the Oregon Coast
Completed Interlock® roofs published in our Job Book, north to south. Each town page shows the profiles, colors and install years.
- Astoria47 roofs since 1998
- Warrenton5 roofs since 1999
- Seaside10 roofs since 1999
- Manzanita6 roofs since 2020
- Nehalem3 roofs since 2001
- Rockaway Beach5 roofs since 2008
- Tillamook17 roofs since 1999
- Pacific City3 roofs since 2016
- Neskowin3 roofs since 2018
- Lincoln City17 roofs since 1998
- Depoe Bay6 roofs since 1999
- Newport7 roofs since 1999
- Waldport4 roofs since 1999
- Florence9 roofs since 1998
- Coos Bay8 roofs since 1998
Oregon Coast metal roof questions
What is the best roof for a house on the Oregon Coast?
For most coast homes it is an aluminum roof. Aluminum contains no iron, so salt air has nothing to rust, while a steel roof depends on its coating and starts to corrode wherever that coating is cut or scratched. The Interlock® system adds four-way interlocking panels with concealed fasteners for the winter storms, and a finish designed and tested to meet AAMA 2605.
Will a steel roof rust at the coast?
It can, and it usually starts at the edges. Steel roofing is protected by a metallic coating and paint; salt spray finds every cut edge, scratch and fastener hole where that protection is broken. Stone-coated steel is still steel under the granules. Aluminum has no iron to rust, which is why we recommend it within reach of the salt.
Is the Interlock warranty valid this close to the ocean?
The Guardian Lifetime Limited Material Warranty certificate has no clause about distance from salt water. Read its exclusions yourself before you sign anything: the coating warranty excludes corrosive, aggressive or industrial atmospheres such as those contaminated with acidic or chemical fumes, and the material warranty excludes dissimilar metals, including dissimilar metal fasteners. Ask every contractor you compare to show you the same clauses in their warranty.
How much wind can an Interlock roof take?
The manufacturer warrants the panels to resist winds of up to 120 mph when installed to manufacturer specification. Separately, ICC-ES evaluation report ESR-1790 lists allowable uplift loads by panel and fastening pattern: up to 177.5 psf for the shingle panels (Slate and Cedar Shingle patterns), 142.5 psf for the hidden-fastener tile and 115 psf for the shake.
Do you install metal roofs on the southern Oregon Coast?
Yes. We install along the whole Oregon Coast from our Portland office, and the same crews, system and warranties apply from Astoria to Brookings. Call (503) 966-2948 to book a roof consultation.
A written price after your roof consultation, from the crew that roofs the coast.
