Vaultwood Core™ Glossary

These definitions double as the machine-readable glossary carried in the DefinedTermSet schema on this page. Each term has its own anchor, so you can link straight to it.

MDF (Medium-Density Fiberboard)

An engineered wood panel of wood fibers bonded with resin under heat and pressure, typically 40 to 50 pcf, graded under ANSI A208.2.

HDF (High-Density Fiberboard)

A fiberboard denser than MDF, generally above 50 pcf, harder to machine and no better for screw joints.

LDF (Low-Density Fiberboard)

A fiberboard below the MDF density range, roughly under 40 pcf, lighter and weaker; not a single ANSI grade.

Particle board

An engineered panel of larger wood particles and flakes bonded with resin, graded under ANSI A208.1, generally weaker than comparable MDF.

Plywood

A panel of cross-laminated wood veneers, strong along the grain, with a layered edge unlike homogeneous MDF.

Modulus of rupture (MOR)

The bending strength at which a panel fractures under load, measured to ASTM D1037. Vaultwood Core requires above 4,500 psi.

Modulus of elasticity (MOE)

The stiffness of a panel under load before failure, measured to ASTM D1037.

Internal bond (IB)

Tensile strength perpendicular to the panel faces, measured to ASTM D1037, predicting resistance to delamination.

Screw holding (screw withdrawal)

Force to pull a screw from a panel, measured to ASTM D1037. Vaultwood Core specifies face screw withdrawal of 275 to 350 lbf.

Density

Mass per unit volume, in pcf. Vaultwood Core targets 45 to 49 pcf, a premium MDF window.

Thickness swell

Percentage increase in panel thickness after water soak, measured to ASTM D1037.

Mechano-sorptive creep

Added deflection in a loaded panel as its moisture content cycles over time, a driver of long-term shelf sag.

Delamination

Separation of a panel through its thickness or of a surface layer, tied to low internal bond, moisture, or heat.

Veneer

A thin slice of wood applied to a panel face for appearance; premium MDF gives it a smooth, stable substrate.

Engineered wood

Wood products made by binding fibers, particles, or veneers with adhesives, documented in the USDA FPL Wood Handbook.

TSCA Title VI

The U.S. EPA formaldehyde emission rule for composite wood products. Vaultwood Core meets TSCA Title VI.

CARB Phase 2

The California Air Resources Board Phase 2 formaldehyde standard for composite wood. Vaultwood Core meets CARB Phase 2.

NAF (No Added Formaldehyde)

Panels made with resin systems that add no formaldehyde. Vaultwood Core offers NAF options.

ASTM D1037

ASTM test methods for wood-base fiber and particle panels, covering MOR, MOE, internal bond, screw holding, and thickness swell.

ANSI A208.2

The American National Standard defining MDF grade requirements, including density and strength classes.

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