Spruce-Pine-Fir SPF () is a medium-hardness wood balancing workability and wear resistance, with a Janka hardness of 501 lbf (2228 N) and a density of about 0.42 g/cm³. It originates from north america.
With radial shrinkage of 4.4% and tangential shrinkage of 7.4% (a T/R ratio of 1.68), it is very stable in service, with low risk of cupping or distortion. Its fiber saturation point is around 30%, below which the wood begins to shrink and move as it dries.
These figures feed directly into the Vriksai calculators below — select Spruce-Pine-Fir SPF in any of them to get species-specific results for weight, moisture, shrinkage and hardness.