Cedar vs Trex Decking: Which Is Better for Seattle?

Seattle gets 37 inches of rain per year — more than Seattle's reputation suggests. That constant moisture is the enemy of cedar decking and the reason Trex composite has become the dominant choice in the Pacific Northwest. Cedar in Seattle's rain: • Absorbs moisture → warps, checks (surface cracks), and eventually rots • Requires complete staining or sealing every 2–3 years or it deteriorates • End-grain at board ends is most vulnerable — capillary absorption pulls water in • Moss grows readily on horizontal cedar in shaded Seattle yards Trex in Seattle's rain: • Engineered to repel water — the composite material doesn't absorb moisture • No warping, no checking, no rot • Moss cannot penetrate composite — nothing to grip on the surface • Fade and stain warranty backed by 25+ years of field performance in wet climates

Trex isn't automatically the right answer for every project. Cedar is still a legitimate choice in specific situations: Cedar is better when: • Budget requires the lowest possible upfront cost • You genuinely enjoy deck maintenance (some homeowners do) • You strongly prefer natural wood aesthetics at close range • The deck is covered or under a roof structure (reduces weather exposure dramatically) • Short ownership timeline (under 7 years) — cedar's lower initial cost is an advantage For most Seattle homeowners planning to stay 10+ years who want outdoor living space they can actually enjoy without weekend maintenance chores: Trex wins.