Deck Cost in the Mid Willamette Valley

Updated 2026-08 ยท Corvallis Home Pros

Quick answer

A new deck in the mid Willamette Valley costs about 28 to 55 dollars per square foot installed, so a 12 by 16 foot deck runs roughly 5,500 to 10,000 dollars and a 16 by 20 foot deck about 9,000 to 17,000 dollars. In the wet valley, composite and sealed wood hold up better than untreated softwood, which can grow moss and rot in the shade.

Deck cost by size

Decks are priced per square foot installed, including framing and railings.

Deck sizePressure treated woodComposite
12 x 16 (192 sq ft)5,500 to 9,000 dollars8,000 to 13,000 dollars
14 x 20 (280 sq ft)8,000 to 12,000 dollars11,000 to 17,000 dollars
16 x 20 (320 sq ft)9,000 to 14,000 dollars13,000 to 20,000 dollars

Decking for the wet valley

The mid valley's wet winters and tree shade are hard on a deck. Untreated softwood grows moss and can rot in damp shade, while pressure treated wood needs regular sealing to hold up. Composite costs more upfront but resists moss, moisture, and rot with little upkeep, which makes it a popular choice for shaded valley decks that see a lot of rain.

Frequently asked questions

How much does a deck cost in the mid valley?

About 28 to 55 dollars per square foot installed, so a 12 by 16 foot deck runs roughly 5,500 to 13,000 dollars depending on material.

Is composite decking worth it in the wet valley?

For many homeowners yes. Composite resists moss, moisture, and rot with little upkeep, which suits shaded, rainy valley decks better than untreated wood.

What decking holds up best in the rain?

Composite and properly sealed pressure treated wood hold up best in the wet valley, while untreated softwood grows moss and can rot in shade.

How much would a 16x20 deck cost?

Roughly 9,000 to 20,000 dollars installed depending on whether you choose pressure treated wood or composite, plus railings and stairs.

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