Estimate and document one signed radial or tangential dimension change for unrestrained solid wood using a USDA FPL table coefficient or a source-owned coefficient.
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A quick decision brief for this specific tool
Inputs that matter
One named unrestrained solid-wood dimensional-change review; evidence basis; responsible review; exact material, cut/growth-ring orientation, measured axis/reference points, MC measurement, use conditions, uncertainty and downstream-boundary records; one radial or tangential direction; two owned MC endpoints; and either a USDA FPL Table 13-5 row, an entered source DCC or an entered source green-to-ovendry shrinkage percentage with explicit units and bounds
Output to expect
One signed directional movement estimate, calculated final dimension, signed percentage change, source/coefficient record, orientation caveat and the full entered-corner movement/final-dimension envelope; positive means swelling and negative means shrinkage
How it works
Use ΔD = Dᵢ × C × (MCf − MCi) only when both MC endpoints are 6%–14%; otherwise, through 30% MC, use ΔD = Dᵢ(MCf − MCi) ÷ [3000/S − 30 + MCi] only with a cited radial or tangential green-to-ovendry shrinkage value, then enumerate the entered dimension, independent endpoint-MC and coefficient-bound corners
The executable model is one unrestrained solid-wood radial or tangential average estimate. It refuses engineered/composite/proprietary treated products, restrained assembly/clearance/structural design, gradients/warp/checking/drying defects, RH/temperature-to-EMC conversion and longitudinal/reaction/cross-grain analysis.
Arithmetic agreement does not validate species/product identity, an individual board, grain angle, measurement method, meter correction, gradients, hysteresis, environment history, coatings, restraint, drying, fit, joinery, fasteners, structure, installation or approval. The corner range is a user-owned sensitivity envelope, not a confidence interval or guarantee.
Choose your path
Built around the job you need to finish
Estimate and retain one documented signed radial or tangential dimension change for unrestrained solid wood from an applicable USDA FPL table coefficient or a source-owned coefficient, without converting climate to MC, predicting an individual board or prescribing clearance, joinery, structure, drying or installation.
Furniture maker reviewing one solid-wood panel width
Distinguish swelling from shrinkage and preserve the exact species, growth-ring orientation, measured axis, MC endpoints and coefficient source before making a separate joinery decision.
Name the tabletop review and responsible maker, record the solid white-oak panel and reference edges, choose plainsawn/tangential Table 13-5, enter 36 in at 8%→12% MC plus owned bounds, then inspect the positive result and caveats.
Gets a reproducible signed swelling estimate, final-dimension range and explicit non-clearance boundary instead of the legacy false no-change result or an automatic joinery allowance.
Use a documented direction-specific coefficient while retaining measurement points, moisture method, conditions and intervention ownership.
Select the conservation record basis and entered-DCC method, cite the exact coefficient, enter same-object radial dimensions and two 6%–14% MC observations, add measurement/coefficient bounds and deliberately retain the reviewed version.
Can compare an arithmetic range without the Tool validating the instrument, diagnosing gradients or approving treatment, restraint or display conditions.
Supplier, laboratory or instructor checking a wider MC transition
Apply the correct total-shrinkage equation outside the DCC range and reject product, drying-defect, EMC and longitudinal substitutions.
Choose the source-owned green-to-ovendry basis, enter a cited radial or tangential total percentage and endpoints through 30% MC, exercise method-range and unsupported-model refusals, then inspect formula, authorities, history/export and exact narrow-screen behavior.
Can reproduce Equation 13-4 and explain why the output is an average unrestrained record—not certification of a board, lot, engineered product, drying schedule or installation.
Authoritative checks for this tool
Outputs and checklists are planning aids. Review the linked current authorities and the records, terms, instructions, and requirements that apply to your exact situation before a consequential decision.
Name one solid-wood material, measured axis and reference points, growth-ring orientation, radial or tangential direction, MC measurement record, use conditions, coefficient locator and responsible review. Engineered products, longitudinal or reaction wood, gradients, warp, checking and restrained assemblies are refused rather than approximated.
Record = material + axis + MC endpoints + coefficient source + review boundary
Use a DCC only within 6%–14% MC
For two endpoints inside 6%–14% MC, select a USDA FPL Table 13-5 species/direction row or enter a documented dimensional-change coefficient. The sign follows final MC minus initial MC, so moisture gain is modeled as swelling rather than discarded as ‘no change.’
ΔD = Dᵢ × C × (MCf − MCi)
Use total shrinkage only through Equation 13-4
When an endpoint lies outside 6%–14% but neither exceeds 30% MC, enter a source-owned radial or tangential green-to-ovendry shrinkage percentage. The Tool also evaluates every corner of the entered dimension, MC and coefficient bounds; that arithmetic range is not a confidence interval or material guarantee.
ΔD = Dᵢ(MCf − MCi) ÷ [3000/S − 30 + MCi]
Updated: August 2026
Example Scenarios
Record a 36 in predominantly plainsawn solid white-oak width at 8% MC and a reviewed 12% endpoint. Table 13-5's tangential DCC produces a positive swelling estimate, while the source, measurement uncertainty and joinery/clearance decision remain visible and separate.
Use an entered, cited radial DCC to compare one artifact dimension between two documented MC observations. Retain reference points, meter method, coating/environment notes and a responsible conservation review instead of treating the arithmetic as intervention approval.
Enter a report-owned green-to-ovendry tangential shrinkage value and use Equation 13-4 for an endpoint outside 6%–14% but no higher than 30% MC. The result remains an average arithmetic record, not certification of a shipment, board or proprietary product.
Common Mistakes to Avoid
✕
Calling a moisture increase ‘no shrinkage’ and reporting no dimensional change
✓
Preserve the sign. Higher final MC produces a positive swelling estimate; lower final MC produces negative shrinkage.
✕
Mixing a green-to-ovendry percentage with the DCC equation
✓
Use each value only with its documented method and direction. DCC is per one percentage-point MC inside 6%–14%; total shrinkage S belongs in Equation 13-4 through 30% MC.
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Treating an average unrestrained estimate as a clearance, structural or installation decision
✓
Retain material, cut, measurement, source, uncertainty, environment, restraint and responsible-review records. Make downstream decisions outside this Tool.
FAQ
The equations use final MC minus initial MC. A higher final MC gives positive swelling; a lower final MC gives negative shrinkage. Equal endpoints give zero modeled change without implying that the board is stable or uniform.
Use the built-in USDA FPL Table 13-5 DCC or a cited entered DCC only when both MC endpoints are 6%–14%. For a wider range through 30% MC, use a cited radial or tangential green-to-ovendry shrinkage percentage with Equation 13-4. Never enter a total shrinkage percent as a DCC.
No. Both MC endpoints must come from an owned measurement or analysis record. The Tool does not convert RH/temperature to EMC, model time-to-equilibrium, validate a moisture meter or resolve gradients.
No. Restraint, grain angle, individual-board variation, coatings, gradients, environment history, fasteners, fit, loads and applicable requirements remain external. A responsible maker, conservator, supplier, engineer or installer must own those decisions.
No. It is the minimum and maximum from the entered dimension, MC and coefficient corners. It does not statistically describe species, board, grain-angle, gradient, hysteresis, drying or measurement variability that was not entered.
About Solid-Wood Dimensional Change Record
Build a reviewable record for one measured solid-wood dimension and moisture-content transition. The Tool reports positive swelling or negative shrinkage, preserves the coefficient source and an entered sensitivity envelope, and leaves EMC prediction, product behavior, restraint, joinery clearance, structure, drying and installation decisions outside.
