Western Redcedar wood movement, board-foot & weight calculator

softwood

Handbook listing: Cedar, western redcedar

Janka
350lbf
Density
22.4lb/ft³
T/R ratio
2.1
Spec. gravity
0.32

Western Redcedar is a North American softwood. It has a Janka side hardness of 350 lbf, a specific gravity of 0.32, and an air-dry density near 22 lb/ft³ (359 kg/m³) (mechanical values at 12% moisture content). It shrinks 5% tangentially and 2.4% radially from green to oven-dry (T/R ratio 2.1), so a 12-inch flatsawn board moves about 0.12 in (≈ 1/8 in) across a 6-point moisture swing (about 6%→12% MC).

Compute Western Redcedar: movement, weight & board footage

Every number below is worked from Western Redcedar's own shrinkage and density figures, not looked up from a table — change the width, moisture swing, or board size in the calculators linked alongside.

Cross-grain movement by board width

Cross-grain change for a 6-point moisture swing (≈ 6%→12% MC), using ΔD = D × (S ÷ 30 ÷ 100) × ΔMC.
Board width Flatsawn (tangential) Quartersawn (radial)
2″ 0.02″ (≈ 1/32 in) 0.01″ (≈ 0 in)
3″ 0.03″ (≈ 1/32 in) 0.014″ (≈ 0 in)
4″ 0.04″ (≈ 1/32 in) 0.019″ (≈ 1/32 in)
6″ 0.06″ (≈ 1/16 in) 0.029″ (≈ 1/32 in)
8″ 0.08″ (≈ 3/32 in) 0.038″ (≈ 1/32 in)
10″ 0.1″ (≈ 3/32 in) 0.048″ (≈ 1/16 in)
12″ 0.12″ (≈ 1/8 in) 0.058″ (≈ 1/16 in)
16″ 0.16″ (≈ 5/32 in) 0.077″ (≈ 1/16 in)

Need a different width or moisture swing? Run the movement calculator preloaded with Western Redcedar. At a T/R ratio of 2.08, Western Redcedar is moderately unstable — it moves substantially more tangentially than radially, so flatsawn stock is noticeably cup-prone and quartersawn stock is worth the extra cost in wide panels.

Board footage & weight, standard sizes

8-foot lengths at Western Redcedar's air-dry density of 22.4 lb/ft³ (12% MC).
Nominal size × length Board feet Weight
1×4 × 8′ 2.67 bd ft 5 lb
1×6 × 8′ 4 bd ft 7.5 lb
1×8 × 8′ 5.33 bd ft 10 lb
1×10 × 8′ 6.67 bd ft 12.4 lb
1×12 × 8′ 8 bd ft 14.9 lb
2×4 × 8′ 5.33 bd ft 10 lb
2×6 × 8′ 8 bd ft 14.9 lb
2×8 × 8′ 10.67 bd ft 19.9 lb

Different length or size? Run the board foot calculator or the weight calculator, both preloaded with Western Redcedar.

Seasonal movement by city

Width change of a 12″ flatsawn board between each city's driest and most-humid month, from USDA equilibrium-moisture-content data.
City Driest month (EMC) Most-humid month (EMC) EMC swing 12″ board movement
Phoenix, AZ Jun · 4.4% Dec · 9% 4.6 pts 0.092″ (≈ 3/32 in)
Chicago, IL May · 12.3% Dec · 15.1% 2.8 pts 0.056″ (≈ 1/16 in)
Miami, FL Apr · 12.2% Sep · 14.4% 2.2 pts 0.044″ (≈ 1/32 in)
Boston, MA Apr · 11.5% Sep · 12.8% 1.3 pts 0.026″ (≈ 1/32 in)
Denver, CO Jul · 8% Dec · 10.5% 2.5 pts 0.05″ (≈ 1/16 in)
Seattle, WA Jul · 12% Dec · 16.9% 4.9 pts 0.098″ (≈ 3/32 in)

Driven by Western Redcedar's tangential shrinkage of 5%. These are outdoor equilibrium-moisture figures, so they are an upper bound — a climate-controlled interior swings less. How this is calculated.

How Western Redcedar compares

Ranked against the 196 species in the Wood Handbook tables this site carries.

See Western Redcedar plotted against every species we carry: the full Janka hardness chart and the full density chart .

Species with a similar working profile

Closest matches on hardness, weight and stability together — useful when Western Redcedar is unavailable or priced out.

Species Janka Density T/R
Butternut 490 lbf 26.6 1.88
Obeche 430 lbf 21 1.8
American Chestnut 540 lbf 30.1 1.97

About Western Redcedar

Western redcedar (Thuja plicata) grows in the Pacific Northwest and along the Pacific Coast to Alaska. It is also called canoe cedar, giant arborvitae, shinglewood, and Pacific redcedar. Western redcedar lumber is produced principally in Washington, followed by Oregon, Idaho, and Montana. The heartwood of western redcedar is reddish or pinkish brown to dull brown, and the sapwood is nearly white. The sapwood is narrow, often not more than 3 cm (1 in.) wide. The wood is generally straight grained and has a uniform but rather coarse texture. It has very low shrinkage. This species is lightweight, moderately soft, low in strength when used as a beam or posts, and low in shock resistance. The heartwood is very resistant to decay. Western redcedar is used principally for shingles, lumber, poles, posts, and piles. The lumber is used for exterior siding, decking, interior woodwork, greenhouse construction, ship and boat building, boxes and crates, sashes, and doors.

Wood Handbook, Chapter 2: Characteristics and Availability of Commercially Important Woods (M.C. Wiemann), USDA Forest Products Laboratory, FPL-GTR-282 (2021), p. 17. Public domain.

Durability & sustainability

Decay resistance: the Wood Handbook rates Western Redcedar heartwood resistant to fungal decay . Ratings are for heartwood only and the table's own note cautions that resistance varies substantially within a species; treat this as a general indicator, not a guarantee, especially for ground contact. Wood Handbook, Chapter 14: Biodeterioration of Wood (Arango, Lebow, Glaeser), USDA Forest Products Laboratory, FPL-GTR-282 (2021), Table 14-1. Public domain.

CITES status: not listed on any CITES Appendix — no international-trade restriction applies to Western Redcedar.

Properties

At 12% moisture content unless noted.
Specific gravity 0.32
Janka hardness (side) 350 lbf
Density (air-dry, 12% MC) 22.4 lb/ft³ (359 kg/m³) ovendry-weight basis: 20 lb/ft³
Weight per board foot (air-dry) 1.87 lb
Radial shrinkage (green→oven-dry) 2.4%
Tangential shrinkage (green→oven-dry) 5%
Volumetric shrinkage (green→oven-dry) 6.8%
T/R ratio (stability indicator) 2.1

Shrinkage is total green-to-oven-dry (Table 4-3); strength values are at 12% MC. Full bases and the derivation formulas are on the methodology page.

Data: USDA Forest Products Laboratory, Wood Handbook FPL-GTR-282 (2021), public domain.