Species data
Red Spruce
Picea rubens - a softwood from eastern North America. Also sold as adirondack spruce.
Properties at a glance
| Janka hardness | 490 lbf |
| Stiffness (MOE) | 1,560,000 psi |
| Specific gravity | 0.43 |
| Density | 26.8 lb/ft3 (430 kg/m3) |
| Weight per board foot | 2.24 lb |
| Shrinkage, green to oven-dry | 7.8% tangential / 3.8% radial |
| Indicative price | $4.00 per board foot (estimated) |
Values are at about 12% moisture content. Density is specific gravity times 62.4; a board foot is one twelfth of a cubic foot, so weight per board foot is that density divided by twelve. Anything marked estimated is our own figure, not a measured one.
How Red Spruce compares
Measured against the 113 solid woods in this database: it is harder than 17% of them, heavier than 15%, and stiffer than 40%. Soft enough to dent in service - worth knowing before using it for a worktop or a floor.
What that means in the shop
A 4/4 board 8 inches wide and 8 feet long is 5.33 board feet, so in Red Spruce it weighs about 11.9 lb. A stack of ten is 119 lb - worth knowing before you load a rack or a car.
Against red oak, the trade's usual yardstick at 1,220 lbf, Red Spruce is about 40% as hard and 61% as heavy.
Its shrinkage is 7.8% tangential against 3.8% radial, a ratio of 2.1 to 1. The wider that ratio, the more unevenly a flatsawn board moves across its width as humidity changes, and the more it wants to cup; anything near or above 2 to 1 is worth quartersawing or restraining for panels and wide tops. This one sits in that range.
Woods of similar hardness
Closest to Red Spruce on hardness in this database: Butternut (490 lbf), Eastern Hemlock (500 lbf), Lodgepole Pine (480 lbf), White Fir (480 lbf). Similar hardness does not mean similar behaviour - check density and movement before substituting one for another.
Working with it
Workability. Clear pieces are simple to mill and bond, but stain tends to absorb unevenly and blotch
Durability. Low decay resistance overall, limiting its use to interior or otherwise protected locations
Typical uses. pulpwood, construction lumber, millwork, crates, musical instrument soundboards.
Related calculators
Sources
MOE (1,560,000 lbf/in2), Janka (490 lbf) and shrinkage (T 7.8%, R 3.8%) from The Wood Database, which cites the USDA FPL Wood Handbook. Specific gravity 0.43 is the 12% MC value (page lists basic 0.37, 12% MC 0.43). No dimensional change coefficient given: Red Spruce has no exact row in the FPL/Hoadley table reproduced by Popular Woodworking, so CT/CR are omitted. Region, uses, durability and workability summarized from The Wood Database. Price indicative.
These calculators are for planning and estimation. Engineering results (shelf sag, wood movement) use published average material properties; real boards vary by grade, grain, moisture and defects. Verify load-bearing designs with a professional.