Pressure-Treated vs Cedar Lumber for Outdoor Builds

Both will last in Pacific Northwest weather — but they age differently and cost very different amounts. Here's how I choose.

Pressure-treated pine is cheaper (often half the cost of cedar), structurally stronger, and rated for ground contact. It's the right choice for anything structural: deck framing, posts, sill plates, retaining-wall bracing.

Cedar is naturally rot- and insect-resistant, lighter, and visually warmer. It weathers to a silver-gray you actually want to look at. Use it for the parts that show — deck boards, fence pickets, trim, planter boxes, exposed beams.

In the Pacific Northwest, PT lumber needs to fully dry before you stain or seal it (often 4–6 weeks after delivery). Skip that step and the stain peels because the wood is still wet from the treatment process. Cedar can be stained immediately.

Cost-wise on a typical deck: framing in PT, deck boards in cedar (or composite). Splitting the materials this way gets you a good-looking deck for less money than going all-cedar without sacrificing structure. For raised garden beds touching food, use cedar — modern PT chemistry is safer than the old CCA but cedar removes the question entirely.