Cedar vs redwood
Western redcedar and redwood are the West Coast woods sold for decks, siding and fences. Redwood is the harder and heavier of the two; the cedar moves a little more across a flatsawn board.
- Old-growth redwood is about 37% harder than western redcedar.
- Old-growth redwood is about 25% heavier than western redcedar.
- Western redcedar has about 14% more movement across a flatsawn board than old-growth redwood.
Each column is the species its page leads with: western redcedar for western red cedar, old-growth redwood for redwood.
Side by side
| Property | Western red cedar | Redwood |
|---|---|---|
| Janka hardness, 12% MC | 350 lbf | 480 lbf |
| Weight, 12% MC | 22.4 lb/ft³ (358 kg/m³) | 28 lb/ft³ (448 kg/m³) |
| Specific gravity, 12% MC | 0.32 | 0.40 |
| Tangential shrinkage | 5.0% | 4.4% |
| Radial shrinkage | 2.4% | 2.6% |
| 12 in flatsawn board, 6% → 12% MC | 0.168 in | 0.148 in |
| 12 in quartersawn board, 6% → 12% MC | 0.08 in | 0.086 in |
| Bending strength (MOR), 12% MC | 7,500 psi | 10,000 psi |
| Stiffness (MOE), 12% MC | 1.11 million psi | 1.34 million psi |
| Crushing strength, 12% MC | 4,560 psi | 6,150 psi |
One source: USDA Forest Products Laboratory, the authority for species properties it measured
Wood Handbook Tables 5-3b, 4-3 and 13-5; weight and movement worked with its Eqs. 4-14 and 13-3. A dash means the Handbook prints no value.
What sets them apart
- Decay
- Western redcedar heartwood is very resistant to decay. Old-growth redwood heartwood has high decay resistance, but heartwood from second-growth trees generally has only low to moderate resistance. (Wood Handbook, p. 2-17)
- Shrinkage
- The Handbook gives western redcedar very low shrinkage and says redwood shrinks and swells comparatively little. Its Table 13-5 coefficients still put the cedar ahead across a flatsawn board: 0.00234 per 1% moisture change against 0.00205 for old-growth redwood. (Wood Handbook, p. 2-17 and 13-17)
- Strength
- Western redcedar is lightweight, moderately soft and low in strength as a beam or post. Old-growth redwood is moderately lightweight, moderately strong and stiff, and moderately hard. (Wood Handbook, p. 2-17)
- Uses
- Western redcedar goes into shingles, siding, decking, greenhouses, boats, sashes and doors. Redwood goes into siding, millwork and, because of its durability, decking, tanks, cooling towers and outdoor furniture. (Wood Handbook, p. 2-17)
For any other pair, open each species page from the wood hub; every page uses the same layout and the same sources.