Field data
  • Janka hardness 830 lbfred oak ≈ 1,290 lbf
  • Density ≈ 36 lb/ft³specific gravity 0.52 at 12% MC
  • Shrinkage — tangential 9.1%flatsawn width, green → ovendry
  • Shrinkage — radial 4.5%quartersawn width
  • T/R ratio 2.0 : 1higher = more cupping in flatsawn stock

Shop notes Hard, resinous, and rot-resistant — decking and timber-frame stock that out-muscles most softwoods and moves like a hardwood.

Seasonal movement at a glance

Width change for western larch across a typical indoor year — 6% moisture content in the heated winter to 12% in a humid summer:

Board widthFlatsawnQuartersawn
6″ 1/8″ (0.117″) 1/16″ (0.058″)
12″ 7/32″ (0.234″) 1/8″ (0.116″)
24″ 15/32″ (0.468″) 7/32″ (0.231″)
36″ 11/16″ (0.702″) 11/32″ (0.347″)

Run your own numbers

Different width, different climate swing — the calculator below is preset to western larch:

Board & conditions
Grain
Conditions given as

Typical swings:

Western Larch questions

How much does western larch move with the seasons?

A 12″-wide flatsawn western larch board moves about 7/32″ across a typical indoor swing from 6% to 12% moisture content; quartersawn, about 1/8″. Its tangential shrinkage is 9.1% and radial 4.5% (green to ovendry) — a high-movement wood.

How hard is western larch?

Western Larch rates about 830 lbf on the Janka scale — softer than red oak but sturdy (red oak is roughly 1,290 lbf). Density runs about 36 lb/ft³ at indoor moisture levels.

Is western larch good for wide panels and tabletops?

Carefully. Its tangential-to-radial ratio of 2.0:1 makes flatsawn boards prone to cupping — choose quartersawn stock for wide glue-ups, alternate growth rings, and fasten tops so they can slide.

Similar species

Longleaf Pine (Heart Pine) · Eastern Redcedar (Aromatic) · Slash Pine · Port-Orford-Cedar · Loblolly Pine (Southern Yellow) · Shortleaf Pine

Shrinkage, specific gravity, and hardness from the Wood Handbook, FPL-GTR-282 (2021 edition), USDA Forest Products Laboratory (public domain). Values are species averages — individual boards vary with growth conditions and how they were dried.