Can Douglas Fir be used for deck boards?

Yes, but it requires pressure treatment or thorough sealing for outdoor use. Without protection, Douglas Fir is susceptible to rot and will deteriorate much faster than cedar deck boards.

Is cedar strong enough for deck framing?

Cedar is generally not recommended for structural deck framing. Its lower density and strength make it better suited for non-structural applications like deck boards, railings, and trim.

Should I use both woods on my deck?

Yes, many professional deck builders use Douglas Fir or pressure-treated lumber for the structural frame (posts, beams, joists) and cedar for the visible deck boards and railings.

Douglas Fir vs Cedar wood grain comparison

decking

Douglas Fir vs Cedar for Decking: Which Is Better? (2026)

Prepared by Lumberama's Wood Comparison Team

|Last updated June 2, 2026|Sources & methodology

Douglas Fir and cedar are both popular domestic softwoods for deck construction, but they serve different roles. Douglas Fir brings superior structural strength, while cedar offers better natural weather resistance. Understanding their complementary strengths helps you choose the right wood, or use both strategically in your deck build.

Douglas Fir

Cedar

Key Takeaways

Douglas Fir and cedar are both popular domestic softwoods for deck construction, but they serve different roles.
Douglas Fir brings superior structural strength, while cedar offers better natural weather resistance.
Understanding their complementary strengths helps you choose the right wood, or use both strategically in your deck build.
These woods complement each other perfectly.
Douglas Fir is the superior structural wood; cedar is the superior decking surface.

Property	Douglas Fir	Cedar
Price/Board Ft	$2-$4	$3-$7
Janka Hardness	660 lbf	350 lbf
Structural Strength	Excellent	Moderate
Rot Resistance	Low without treatment	Good naturally
Weight	Moderate-heavy	Light
Appearance	Warm pinkish-tan	Reddish to light brown
Stain Absorption	Moderate	Excellent

Douglas Fir

Pros

Superior structural strength, Harder surface resists wear, More affordable, Excellent for framing and joists

Cons

Poor natural rot resistance, Requires treatment for outdoor use, Splinters more than cedar, Heavier to work with

Cedar

Pros

Natural rot and insect resistance, Beautiful aromatic wood, Lightweight and workable, Excellent dimensional stability

Cons

Weak structural strength, Softer surface dents easily, More expensive, Not suitable for structural framing

Best Use Cases

Choose Douglas Fir for deck framing, joists, and structural components. Choose cedar for deck boards, railings, and visible surfaces. Many builders use both: Fir for structure, cedar for surface.

Verdict

These woods complement each other perfectly. Douglas Fir is the superior structural wood; cedar is the superior decking surface. The best decks often use both materials strategically.