Species data
Sweetgum
Liquidambar styraciflua - a hardwood from southeastern United States. Also sold as redgum, sapgum, satin walnut.
Properties at a glance
| Janka hardness | 850 lbf |
| Stiffness (MOE) | 1,640,000 psi |
| Specific gravity | 0.55 |
| Density | 34.3 lb/ft3 (550 kg/m3) |
| Weight per board foot | 2.86 lb |
| Shrinkage, green to oven-dry | 10.2% tangential / 5.3% radial |
| Indicative price | $3.50 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 Sweetgum compares
Measured against the 113 solid woods in this database: it is harder than 40% of them, heavier than 36%, and stiffer than 53%.
What that means in the shop
A 4/4 board 8 inches wide and 8 feet long is 5.33 board feet, so in Sweetgum it weighs about 15.3 lb. A stack of ten is 153 lb - worth knowing before you load a rack or a car.
Against red oak, the trade's usual yardstick at 1,220 lbf, Sweetgum is about 70% as hard and 79% as heavy.
Its shrinkage is 10.2% tangential against 5.3% radial, a ratio of 1.9 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 moves comparatively evenly.
Woods of similar hardness
Closest to Sweetgum on hardness in this database: African Mahogany (850 lbf), Bigleaf Maple (850 lbf), Black Ash (850 lbf), Red Elm (860 lbf). Similar hardness does not mean similar behaviour - check density and movement before substituting one for another.
Working with it
Workability. Mostly easy, but interlocked grain tears and it warps badly while drying; turns, glues, stains and finishes well
Durability. Heartwood ranges moderately durable to non-durable, sapwood perishable, and insects attack it readily
Typical uses. furniture, veneer, plywood, interior trim, boxes, turned objects.
Related calculators
Sources
MOE, SG (12% MC), Janka and shrinkage from The Wood Database (cites USDA FPL Wood Handbook). Uses, region, durability and workability summarized from The Wood Database. Sweetgum is not listed in the FPL/Hoadley dimensional change coefficient table (Popular Woodworking reproduction), so CT/CR are omitted. 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.