Openings where a portion of the wood substance of the knot has dropped out, or where cross checks have occurred to present an opening.

Separation of plies or layers of wood or other materials through failure at an adhesive joint.

Stains in wood substances. Common are sap stains and blue stains.

Form of incipient decay characterized by a dull and lifeless appearance of the wood, accompanied by a lack of strength and a softening of the wood substance.

Strip along the outside edges of the two sides and/or top and bottom of a door.

Hardwood plywood, high pressure laminate, hardboard, or composition panels or combination thereof, whether flat or configured, which are used for the faces of flush doors.

Repair to an open defect with fast-drying plastic putty.

Series of interlocking fingers cut on the ends of two pieces of wood which mesh together and are held by adhesive.

Open splits in the inner ply or plies, or improperly joined veneer when joined veneers are used for inner plies.

Well-defined openings between rings of annual growth, usually containing gum or pitch.

Lumber dried in a closed chamber in which the removal of moisture is controlled by artificial heat and usually by relative humidity.

Very fine lines that appear across a panel that may look as if they are raised resulting from some defect.

Cross section of a branch or limb with grain usually running at right angles to that of the wood in which it occurs.

Voids produced by knots dropping from the wood in which they were originally embedded.

Sound knots less than 1/4-in. in diameter.

Condition where veneers composing plywood are so misplaced that one piece overlaps the other and does not make a smooth joint.

Concealed block same thickness as a door stile or core which is adjacent to the inside edge of the stile at the midpoint and into which a lock is fitted.

Matching wood pieces carefully inserted and glued into the door face after defective portions have been removed.

Bleeding resin.

Cross or horizontal pieces of the framework of a wood flush door

Bottom cross or horizontal piece of a door.

Top cross or horizontal piece of a door.

Separation along the grain, the greater part of which occurs between the rings of annual growth.

A split repaired in a piece of wood veneer.

Irregular surfaces visible on the face of a wood flush door.

By industry practice, a standard door is book size in both width and height.

Upright or vertical pieces of the framework of a wood flush door.

Strips of gummed paper used to hold edges of veneer together at the joints before gluing.

Visible irregularities in surface of face of plywood caused by corresponding irregularities in the underlaying plies such as core laps, voids, or extraneous matter.

The selection includes exterior entrance doors, interior passage doors, French or casement doors, bi-fold doors, side lights, patio sliding and swinging doors, thermal insulated-glass doors, louver do ors, screen doors, and specialty door products. Several selected types are illustrated here.

Scars in wood generally caused by the stems of vines clinging by their hair-like roots to the tree trunk.

Any distortion in the plane of a door itself and not its relationship to the frame or jamb in which it is to be hung. Warp includes bow, cup, and twist:

A flatwise deviation from a straight line drawn from top to bottom; a curvature along the width of the door.

A deviation from a straight line drawn from side-to-side; a curvature along the width of a door.

Stressed skin construction consisting of a core, stiles, and rails, and or/edge banding, two face panels, almost all of which are wood, wood derivative. materials, or high pressure decorative laminate.

            Groove or resulting scar tissue in wood caused by worms or other borers.