Wood Movement

Software for Estimating Shrink and Swell

Wood Shrink/Swell estimator - A web-based program to estimate shrink/ swell in wood. Can also be used on any mobile device!

EMC (Equilibrium Moisture Content) Map of the US by Month

Time-Lapse videos of wood movement:

• Adsorption - video shows how rapidly a small block of dried hybrid poplar adsorbs colored water
• Casehardening test prongs - video shows how prongs close as drying stresses are relieved
• Warp in laminated western juniper flooring - warp due to unbalanced construction and differential shrinkage between solid juniper face and baltic birch plywood backer.
• Development of end checks and splits in a Port-Orford-cedar 6x6 as it dries.
• Video of warp in laminated western juniper paneling - warp due to unbalanced construction and juvenile wood
• Video of tangential shrinkage in a small piece of hard maple veneer
• Video of checks (lengthwise splits in the veneer) developing in maple plywood
• Progress of check development in maple veneer plywood over 4 hours. Each Stage is equal to 10 minutes.  Red indicates developing strain in the veneer.
• Warp in pencils due to differential shrinkage of the 2 'slats' used to produce a pencil:
  • Single pencil stored in initial conditions of 86°F and 90% relative humidity for 7 days then moved to room at 75°F and 36% relative humidity. Movement is subtle, but tip moves relative to the ruler.
  • Several pencils warping standing on end