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Air Dried
Seasoned by exposure to the atmosphere, in the open or under cover, without artificial heat.
All-heart
Of heartwood throughout; that is, free of sapwood.
Architectural Woodwork
Fine custom woodworking, so varied in design and complexity that it becomes difficult to define, specified for special applications and functions by design professionals and created by woodworkers. It includes all exterior and interior woodwork exposed to view in a finished building (except lumber yard or specialty items of flooring, shingles, exposed roof decking, ceiling, siding, structural wood trusses and rafters, and overhead-type doors), including all exposed wood, plywood, high and low pressure decorative laminates and wood doors. Items made of other materials are included only if called for in the specifications. Finishing may be included if specified. Site installation may also be included if specified.
Arris
In architecture, a sharp edge formed by the meeting of two flat or curved surfaces.
Articulated Joint
In architectural paneling, joint details which allow for field variations.
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Back
The side reverse to the face of a panel, or the poorer side of a panel in any grade of plywood calling for a face and back.
Backed Out
Wide, shallow area machined on the back surface of wide solid mouldings and some frames. Allows the item to span irregular surfaces.
Baluster
In stairwork, the vertical members which support the handrail.
Barber Pole
An effect in book matching of veneers resulting from tight and loose sides of veneers causing different light reflections when finished.
Bark Pocket
Comparatively small area of bark around which normal wood has grown. Also a patch of bark partially or wholly enclosed in the wood. Classified by size the same as pitch pockets.
Base Mouldings
Mouldings used to trim the intersection of a wall or cabinet and the floor.
Base Shoe
A small moulding combined with a base moulding to complete the trimming of the wall and floor intersection.
Bevel
A machine angle other than a right angle, i.e., a 3-degree bevel which is equivalent to a 1/8 inch drop in a 2-inch span (1 mm in 16 mm).
Beveled Edge
An edge of the door which forms an angle of less than 90 degrees with the wide face of the door, such as a 3 degree beveled edge.
Board Foot
A piece of wood one inch thick, twelve inches long and twelve inches wide, or its equivalent (144 cubic inches). When stock is less than one inch thick it is usually calculated as if it were a full one-inch thick.
Book Match
Matching between adjacent veneer leaves on one panel face. Ever other piece of veneer is turned over, so that adjacent leaves are “opened” as two pages in a book. The fibers of the wood, slanting in opposite directions in the adjacent leaves create a characteristic light and dark effect when the surface is seen from an angle.
Bow
A deviation flat wise from a straight line drawn from end to end of a piece. It is measured at the point of greatest distance from the straight line.
Burl
A figure created by abnormal growth, or response to injury, that forms an interwoven, contorted, or gnarly mass of dense woody tissue on the trunk or branch or the tree. Burls are usually small and characterized by eye-like marking surrounded by swirls and clusters of distorted tissues.
Butt Joint
A joint formed by square edge surfaces (ends, edges, faces) coming together; end butt joint, edge butt joint.
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Casework
Base and wall cabinets, display fixtures, and storage shelves. The generic term for both “boxes” and special desks, reception counters, nurses stations, and the like. Generally includes the tops and work surfaces.
Casing
Generally, a moulding placed around a doorframe or window frame.
Cathedral
A grain appearance characterized by a series of stacked and inverted “V” or cathedral type of springwood (earlywood) summerwood (latewood) patterns common in plain sliced (flat-cut) veneer and plain sawn lumber.
Chair Rail
A decorative moulding placed at a height on the wall comparable to the place where the back of a chair would impact the wall surface.
Chatter
Lines appearing across the panel or board at right angles to the grain giving the appearance of one or more corrugations resulting from bad setting of sanding equipment or planning knives.
Checks
Small slits running parallel to grain of wood, caused chiefly by strains produced in seasoning.
Chip Marks
Shallow depressions or indentations on or in the surface of dressed lumber caused by shavings or chips getting embedded in the surface during dressing. Very light chip marks – not over 0.4mm [1/64 inch] deep. Light chip marks – not over 0.8 mm [1/32 inch] deep. Medium chip marks – not over 1.6mm [1/16 inch] deep. Heavy chip marks – not over 3.2mm [1/8 inch] deep.
Chipped Grain
A barely perceptible irregularity in the surface of a piece caused when particles of wood are chipped or broken below the line of cut. It is too small to be classed as torn grain and is not considered unless in excess of 25% of the surface involved.
Cleats
In closet and utility shelving, the wood members furnished to support the shelf.
Close and Open Grain
The size and distribution of the cellular structure of the wood influences the appearance and uniformity. Open Grain hardwoods such as Elm, Oak, Ash, and Chestnut are “ring-porous” species. These species have distinct figure and grain patterns. Close Grain hardwoods, such as Cherry, Maple, Birch, Yellow Poplar, are “diffuse-porous” species. Most North American diffuse-porous woods have small, dense pores resulting in less distinct figure and grain. Some tropical diffuse-porous species (e.g., Mahogany) have rather large pores. For the purposes of opaque finishes, materials other than Close Grain wood such as Medium Density Overlay (MDO), Medium Density Fiberboard (MDF), and others could be substituted with excellent results.
Comb Grain
A quality of rift veneer with exceptionally straight grain and closely spaced growth increments, often said to resemble the appearance on long strands of combed hair.
Cope
To cut or shape the end of a moulded wood member so that it will cover and fit the contour of the sticking coping at the joint.
Core
Flush doors and plywood are said to have a “core” material and/or construction. Typical cores are lumber core (also known as stave lumber core); veneer core; particleboard core; or fiberboard core.
Cove Mouldings
Similar to crown moulding, often smaller in size and less decorative.
Crook
A deviation edgewise from a straight line drawn from end to end of a piece . It is measured at the point of greatest distance from the straight line.
Cross Figure
A series of naturally occurring figure effects characterized by mild or dominant patterns across the grain in some faces. For example, a washboard effect occurs in fiddleback cross figure; and cross wrinkles occur in the mottle figure. Sometimes called cross fire.
Cross Grain
Applied to wood in which the grain is not running lengthwise of the material of in one direction. The irregularity is due to interlocked fiber, or to uneven annual rings, or to intersection of branch and stem.
Crotch
Crotch come from the portion of a tree just below the point where it forks into two limbs. The grain is crushed and twisted, creating a variety of plume and flame figures, often resembling a well formed feather. The outside of the block produces a swirl figure that changes to full crotch figure as the cutting approaches the center of the block.
Crown Mouldings
Mouldings used to accent ceiling intersections and traditional pediments and casework tops.
Cup
A deviation in the face of a piece from a straight line drawn from edge to edge of a piece. It is measured at the point of greatest distance from the straight line.
Curly
Figure which occurs when the fibers are distorted producing a wavy or curly effect in the lumber or veneer. Primarily found in maple or birch.
Custom Grade
The middle or normal Grade in both material and workmanship, and intended for high-quality, conventional work.
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Dado Joint
A groove cut across the grain of the face of a member to receive the edge or end thickness of another member.
Dead Knots (Open Knots)
Openings where a portion of the wood substance of the knot has dropped out or where cross checks have occurred to present and opening.
Defect
Open joints, knotholes, cracks, loose knots, wormholes, gaps, voids, or other openings interrupting the smooth continuity of the wood surface.
Delamination
Separation of the plies or layers of wood or other materials through failure of the adhesive joint.
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Eased Edges
For the vast majority of work a sharp arris or edge is not permitted. Such edges are traditionally “eased” by lightly striking the edge with a fine abrasive. Less often, or as a design element, such edges are machined to a small radius.
Economy Grade
The lower Grade in both material and workmanship, and intended for work where price outweighs quality considerations.
Edge Joint
When the edges of boards are glued together to increase the width.
End Match
Matching between adjacent veneer leaves on one panel face. Veneer leaves are book matched end to end as well as side to side. Generally use for very tall panels or for projects in which only short length veneers are available.
Equilibrium Moisture Content
The moisture content at which wood neither gains nor loses moisture when surrounded by air at a given relative humidity and temperature.
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Face
The better side of any pane in which the outer plies are of different veneer grads. Also either side of a panel in which there is no difference in veneer grade of the outer plies.
Face Joint
When the faces of boards are glued together to increase the thickness.
Face Veneer
The outermost exposed wood veneer surface of a veneered wood door, panels or other component exposed to view when the project is completed.
Figure
The natural pattern produced in the wood surface by annual growth rings, rays, knots, and natural deviations from the normal grain, such as interlocked and wavy grain, and irregular coloration.
Finger Joint
When the ends of two pieces of lumber are cut to an identically matching set. Used most commonly to increase the length of the board. A series of interlocking fingers are precision cut on the ends of two pieces of wood which mesh together and are held in place with adhesive.
Fire Rated
Fire retardant particleboard is available with an Underwriters Laboratory (UL) stamp for class 1 fire rating (Flame Spread 20, Smoke Developed 25). Fire rated doors are available with particle board and mineral cores for ratings up to 1-1/2 hours. It is the responsibility of the specifier to indicate what fire retardant classification is required for a particular product. In the absence of such a specified rating, the woodworker my supply unrated product.
Flake
More properly called fleck, and sometimes referred to as silver grain. Created when the veneer knife of saw passes through the medullary rays, wood rays, or pith rays in such a manner as to reveal the natural wavy, pencil-like stripes in the wood.
Flat Grain (FG) [Slash Grain (SG)]
A piece or pieces sawn approximately parallel to the annual growth rings so that all or some of the rings form an angle of less than 45 degrees with the surface of the piece.
Flitch
A hewn or sawn log made ready for veneer production or the actual veneer slices of one half log, kept in order, used for he production of fine plywood panels. To determine the approximate amount of face veneer required, multiply the panel surface area by 3. This ration may have to be increased to accommodate exacting requirements of appearance when the flitch contains a wide range of characteristics.
Flush Construction
Cabinet construction in which door and drawer faces are set within and flush with the body members or face frames of the cabinet with spaces between face surfaces sufficient for operating clearance.
Flush Overlay
Cabinet construction in which door and drawer faces cover the body members of the cabinet with spaces between face surfaces sufficient for operating clearance.3>Eased Edges
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Grain
Arrangement of wood fibers and pores evident on cut and/or finished wood products. The direction, size, arrangement and appearance of the fibers in wood or veneer. The appearance of the grain varies with both the species and the cut.
Gum Pockets
Well-defined openings between rings of annual growth, containing gum or evidence of prior gum accumulation.
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Hairline
Thin, perceptible line showing at the joint of two pieces of wood.
Handrail
In stairwork, the member which follows the pitch of the stair for grasping by the hand.
Hardboard
Constructed of inter-felted fibers consolidated and formed under heat and pressure into panels.
Hardness
Generally defined as resistance to indentation using a modified Janka hardness test.
Heartwood
The inactive cells of the inner tree, located below the Sapwood. The cell cavities of the heartwood may contain deposit which make it darker in color that the sapwood.
HPDL
Abbreviation for high pressure decorative laminate.
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KCPI
Stands for knife cuts per inch. Generally used when describing the result of moulded profiles or S4S materials.
Kerf
The groove or notch made as a saw passes through wood. Also the wood removed by the saw in parting the material.
Kiln-Dried
Lumber dried in a closed chamber in which the removal of moisture is controlled by artificial heat and usually by relative humidity.
Knife Marks
The imprints or markings of the machine knives on the surface of dressed lumber.
Knot
Cross section of tree branch or limb with grain usually running at right angles to that of the piece of wood in which it occurs.
Knots
Openings where a portion of the wood substance of the knot was dropped out, or where cross checks have occurred to present an opening.
Knots, Sound Tight
Knots that are solid across their face and fixed by growth to retain their place.
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Machine Bite
A depressed cut of the machine knives at the end of a piece.
Mechanical Fastener
The generic term used for securing devices used in the fabrication and/or installation of millwork such as dowels, dowel screws, spline, nails, screws, bolts, pinks shot pins, etc.
Medium Density Fiberboard (MDF)
The generic name for a panel manufactured from lignocellulosic fibers combined with a synthetic resin or other suitable binder and bonded together under heat and pressure in a hot press by a process in which the added binder creates the entire bond.
Medium Density Overlay
A thermosetting resin impregnated paper applied to a panel product particularly well suited for opaque (paint) finishes. Most versions are highly weather resistant.
Mineral Streak
Discoloration, often brown, black or green in tone.
Miter Joint
When two surfaces are cut at any angle (typically 45 degrees).
Miterfold
Made from a single panel in one machining process, includes placement of tape, machining, application of adhesive, folding, glue, clamp and clean.
Moisture Content
The amount of water contained in wood, expressed as a percentage that indicates the relative weight of the water in the piece compared to the oven dry weight. The optimum moisture content of wood for interior use is between 5-13% depending on the part of the country.
Mortise and Tenon Joint
When one piece is slotted (mortise) to fit the tongue (tenon) of the adjoining piece.
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Newel Post
In stairwork an upright post which supports or receives the handrail at critical points of the stair such as starting, landing, or top.
Nosing
In stairwork the shaped edge or edges, of tread or landing.
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Open Grain and Close Grain
The size and distribution of the cellular structure of the wood influences the appearance and uniformity. Open Grain hardwoods such as Elm, Oak, Ash, and Chestnut are “ring-porous” species. These species have distinct figure and grain patterns. Close Grain hardwoods, such as Cherry, Maple, Birch, Yellow Poplar, are “diffuse-porous” species. Most North American diffuse-porous woods have small, dense pores resulting in less distinct figure and grain. Some tropical diffuse-porous species (e.g., Mahogany) have rather large pores. For the purposes of opaque finishes, materials other than Close Grain wood such as Medium Density Overlay (MDO), Medium Density Fiberboard (MDF), and others could be substituted with excellent results.
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Pitch
Bleeding resin. Small area, usually black or dark brown in color, containing a resinous material which still is partly liquid.
Pitch Pocket
Well-defined opening between annual growth rings which contains pitch.
Plain Sawn
Yields broad grain pattern, widest boards and least waste from the log.
Plain Slicing
Most common for hardwood plywood, the log is cut in half. One half is placed onto a carriage and moved up and down past a fixed knife to produce the veneers. Veneer sliced parallel to the pith of the log and approximately tangent to the growth rings to achieve flat cut veneer. Each piece is generally place in a stack and kept in order. One half log, sliced this way, is called a flitch.
Premium Grade
The highest Grade available in both material and workmanship intended for the finest work. This is naturally the most expensive grade.
PVC
Abbreviation for polyvinyl chloride, a synthetic decorative coating or edge banding.
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Quarter Sawn
Refers to solid lumber cutting. Available in limited amounts in certain species. Yields straight grain, narrow boards, “fleck” or figure in some species. More expensive that plain sawn.
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Rabbet Joint
A groove cut across the grain of the face of a member at an edge or end to receive the edge or end thickness of another member.
Railings
In stairwork, the member which follows the pitch of the stair for grasping by the hand.
Rails
The cross or horizontal pieces of a stile and rail assembly or the cross pieces of the core assembly of a wood flush door or panel.
Raised Panel
Traditional door or wall panel with a bevel edge captured in a stile and rail frame.
Reveal Overlay
Cabinet construction in which door and drawer faces partially cover the body members or face frames of the cabinet with spaces between face surfaces creating decorative reveals.
Rift Cut
Usually referring to veneers, but can be applied to solid lumber (usually as Rift Sawn), this method is similar to Quarter Slicing, but accentuates the vertical grain and minimizes the fleck of the finished material. Veneer produced by cutting at a slight right angle to the radial to produce quartered appearance.
Riser
In stairwork, the vertical member between treads. Riser may be omitted in certain stair designs.
Running Trim
Generally combined in the term “Standing and Running Trim” and refers to the trims of random, longer length delivered to the jobsite (e.g., baseboard, chair rail, crown moulding, etc.).
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S4S
Means surfaced four sides, and generally refers to the process of reducing nominal sized rough lumber to finished widths and thicknesses.
Sapwood
Performs the living functions of the tree. Located just below the cambium layer. Generally lighter in color than the heartwood.
Shake
A lengthwise separation along the grain of wood in which the greater part occurs between the rings of annual growth.
Skin
The hardwood plywood (usually 3-ply), hardboard or composition panel, whether flat or configured, which are used for facings for flush wood doors, bending laminations, finished end panels and the like.
Softwood
Generally obtained from coniferous trees. Does not refer to the specific density or resistance to wear and abuse.
Sound
The woodworking term meaning free of decay.
Standing Trim
Generally combined in the term “Standing and Running Trim” and refers to the trims of fixed length delivered to the jobsite (e.g. door jambs and casings, pre-machined window stools, etc.).
Stile and Rail Construction
Stile and rail construction for wall paneling and doors is one of the finest uses of wood as an interior finish.
Stiles/Vertical Edges
The upright or vertical pieces of stile and rail assemblies or the vertical members of the core assembly of a wood flush door.
Stops
Generally a moulding used to “stop” a door or window in its frame.
Stringer
In stairwork, member which supports and establishes the tread and riser relationship.
Substrate
Generally used to describe a panel product (see also Core) upon which a decorative finish material is applied.
Surface Check
A check of little depth, and chiefly confined to the surface.
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Tongue and Groove
Mating groove and tongue milled into the members, generally on the edges to improve alignment and glue surface area.
Torn Grain
An irregularity in the surface of a piece where wood has been torn or broken out by surfacing. Very light torn grain – not over 0.4mm [1/64 inch] deep. Light torn grain – not over 0.8 mm [1/32 inch] deep. Medium torn grain – not over 1.6mm [1/16 inch] deep. Heavy torn grain – not over 3.2mm [1/8 inch] deep. Very heavy torn grain – over 3.2mm [1/8 inch] deep.
Tread
In stairwork, the horizontal member which is stepped upon.
Twist
A deviation flat wise, or a combination of flat wise and edgewise, in the form of a curl or spiral, and the amount is the distance an edge of a piece at one end is raised above a flat surface against which both edges at the opposite end are resting snugly.
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Veneer
A thin sheet of wood, rotary cut, sliced, or sawed from a log, bolt, or flitch. Veneer may be referred to as a ply when assembled into a pane.
Volute
In stairwork a spiral or scroll end of a handrail, generally atop a newel post.
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Wainscot
A lower interior wall surface (usually about 1m [ 3 to 4 feet] above the floor) that contrasts with the wall surface above it; an interior wall of two different interior wall surfaces, one above the other.
Wane
Bark or lack of wood from any cause, except eased edges on the edge or corner of a piece of lumber.
Warp
Any deviation from a true or plane surface, including bow, crook, cup, twist, or any combination thereof. Warp restrictions are based on the average from of warp as it occurs normally and any variation from this average form, such as short kinks, shall be appraised according to its equivalent effect. Pieces containing two or more forms of warp shall be appraised according to the combine effect in determining the amount permissible. See definitions for a Bow, Crook, Cup or Twist for more details.
