Oregon is two climate zones split by the Cascades, and the western half gets the rainiest weather of any major US market. Portland, Eugene, Salem, Corvallis, and Hillsboro average 40-45 inches of annual rainfall spread over 150+ rain days per year. The Oregon coast — Astoria, Tillamook, Newport, Coos Bay, Brookings — gets 70-90 inches. That combination of constant moisture plus mild year-round temperatures (rarely below freezing west of the Cascades, rarely above 85°F) creates a year-round mold and mildew environment that attacks stairlift motor housings in ways standard equipment isn't designed for. Every Oregon install west of I-5 ships with IP54-sealed motor housings, anti-mold gaskets, and 316-stainless fasteners as a baseline. Not an upcharge.
The dominant Portland housing type is the 1905-1925 craftsman bungalow with a straight 13-tread main staircase off the front parlor. These are found in Ladd's Addition, Laurelhurst, Irvington, Sellwood-Moreland, and Alameda — and they're the most stairlift-friendly stock in the state because the staircase is straight, wide (36-38 inches), and structurally sound. A standard straight rail bolts into the original Douglas fir treads with no modification. The problem is tread finish: many Portland craftsman owners have refinished original fir with thin modern polyurethane, which is too slippery for some rail mounting feet. We use a 40-grit prep sand under each mounting foot — standard.
The Willamette Valley also has a large population of 1960s-1980s split-level and ranch homes in Beaverton, Tigard, Hillsboro, Gresham, Eugene, and Salem. Split-levels need curved rails with a half-landing bend. Ranches with daylight basements on sloped Willamette Valley lots need a short interior rail from garage to main floor. The Oregon coast has its own housing story: 1940s-1970s beach cottages in Lincoln City, Cannon Beach, Gearhart, and Seaside that have exterior wood stairs facing constant salt spray and horizontal rain.
Built for the Oregon climate
Oregon's climate splits three ways. West of the Cascades — Portland, Eugene, Salem, Corvallis, Hillsboro, Beaverton — the issue is chronic moisture: 40-45 inches of rain over 150+ rain days per year, combined with mild temperatures that never dry out the ambient humidity. Standard stairlift motor housings grow mildew on the internal ventilation plates within 3-5 years. Our Willamette Valley spec uses IP54-sealed housings with anti-mold silicone gaskets and treated motor windings. The Oregon coast (Astoria to Brookings) gets 70-90 inches of rain plus constant salt spray — coastal installs get marine-grade epoxy rail coating and 316-stainless fasteners standard. East of the Cascades — Bend, Redmond, Klamath Falls, La Grande, Baker City — the issue flips to cold and dry: winter lows hit -5°F to -15°F in the higher elevations, so Eastern Oregon installs get the cold-weather battery variant rated to -20°F. All three upgrades are baseline, not upcharges.