Pressure treated vs cedar for deck and fence repairs
By Jeff Rabkin, JustFix Wood · Published September 25, 2026
When I replace a board or post, the first question is what to replace it with. For most repairs around here, it comes down to pressure-treated pine or cedar.
Pressure-treated lumber
Treated pine is soaked with preservatives that resist rot and insects. It's strong and less expensive, which makes it the standard for framing: posts, joists and beams. Anything touching the ground should be lumber rated for ground contact.
It can shrink, twist and check as it dries, and it needs to be sealed or stained to look good over time. Treated lumber is also corrosive to ordinary steel, so it needs fasteners and hangers rated for it.
Cedar
Cedar has natural rot resistance, stays straighter, and looks better. It's common for deck boards, railings, fence pickets and trim. It's softer and costs more, and it isn't the right choice for structural posts in the ground.
Matching what's there
For repairs, matching the existing material usually matters more than which one is "better." A new cedar board in an old cedar deck will weather in. A mix of materials can look patchy for a season or two.
What about composite? It's a good material, but it's hard to patch into a wood deck, and it doesn't replace structural wood underneath.
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