What Makes a Good Roofing System for Pacific Northwest Weather?

Roofs in Arizona fail from UV and heat. Roofs in the Midwest fail from hail and freeze-thaw. Roofs in the Willamette Valley and the Mt. Hood corridor fail from something less dramatic and more relentless: sustained moisture, organic growth, and wind-driven rain over a long wet season.

1. Flexibility over brittleness

Months of damp, then a cold snap, then damp again. Standard asphalt shingles get brittle and crack. A polymer-modified (rubberized) shingle like Malarkey's NEX product stays more flexible, and Malarkey publishes tear strength well above the industry standard.

2. Granules that stay put

Granules are the shingle's shield. Once they wash into the gutter, the asphalt underneath is exposed and the clock speeds up. Granule adhesion is one of the least discussed and most important specs for a wet climate.

3. Sealing against sideways rain

Rain here does not always fall straight down, so sealing details matter — and correct flashing at chimneys, skylights, walls, and dormers matters just as much as the shingle itself.

4. Ventilation

A roof can also fail from underneath. Trapped heat and moisture in an under-ventilated attic degrade decking and shorten shingle life. When we replace a roof we review ventilation and update it if it is inadequate — see our roof replacement page for how that fits into the process.

5. Drainage and maintenance

No system survives a valley packed with fir needles or a gutter that has not drained in three years. Roof maintenance and gutter cleaning are not upsells here; they are the difference between getting 30 years out of a roof and getting 18.

6. Algae and moss resistance, with realistic expectations

Algae-resistant granule options help reduce streaking, and they are available on certain Malarkey lines. No shingle stops moss on its own in this climate — that still takes moss removal before growth thickens and lifts shingle edges.