A
Acrylic	A synthetic resin used extensively for exterior latex paints and some high quality interior latex paints.
Additives	Chemicals which are added to coatings in small amounts to alter the physical or chemical properties of the finish. For example, certain additives can reduce the drying time of alkyd (oil-based) finishes
Adhesion	The union between a coating film and the material with which it is in contact. The latter may be another film of paint (intercoat adhesion) or any other material such as wood.
Adhesive	A substance capable of holding materials together by surface attachment. It is a general term and includes cements, mucilage, paste, and glue.
Adhesive, Cold-Setting	An adhesive that sets at temperatures below 20¡C (68¡F).
Adhesive, Construction	Any adhesive used to assemble primary building materials such as floor sheathing into components during building construction. The term is most commonly applied to elastomer-based, mastic-type adhesives.
Adhesive, Contact	An adhesive which, while apparently dry to the touch, will adhere instantaneously to itself upon contact. The terms contact bond adhesive, or dry bond adhesive, are also used.
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Adhesive, Gap-Filling	Adhesive suitable for use where the surtaces to be joined may not be in close or continuous contact owing either to the impossibility of applying adequate pressure or to slight inaccuracies in matching mating surtaces.
Adhesive, Hot-Melt	An adhesive that is applied in a molten state and forms a bond on cooling to a solid state.
Adhesive, Room-Temperature Setting	An adhesive that sets in the temperature range of 20 to 30¡C (68 to 86¡F).
Adhesive, Working Life (pot life)	The period of time during which an adhesive, after mixing with catalyst, solvent, or other compounding ingredients, remains suitable for use.
Alkyds	Oil based coatings used in a wide variety of protective coatings, such as floor and deck paint enamels, wall and trim paints, stains, and varnishes.
Annual Growth Ring	The layer of wood growth added each growing season to the diameter of the tree. In the temperate zone the annual growth rings of many species such as oaks and pines are readily distinguished because of differences in the cells formed during the early and late parts of the seasons.
Axial Force	A push (compression) or pull (tension) acting along the length of a member, expressed in kilonewtons (pounds).
Axial Stress	The axial force acting at a point along the length of a member divided by the cross-sectional area of a member, expressed in kilopascals (pounds per square inch).
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B
Back Priming	Application of paint to the back of woodwork and exterior siding to prevent moisture from getting into the wood, causing the grain to swell and the paint to peel.
Bark Pocket	An opening between annual growth rings that contains bark. Bark pockets appear as dark streaks on radial surtaces and as rounded areas on tangential surtaces.
Beam	A structural member loaded on its narrow face.
Bearing	The contact area over which one structural element, such as a truss, is supported on another structural element such as a wall.
Bearing Stud Wall	An exterior or interior wall designed to act as a structural element by transmitting vertical loads to the foundation.
Birdseye	Small localized areas in wood with the fibres indented to form small circular or elliptical figures on the tangential surface which are used for decorative purposes. Sometimes found in sugar maple but only rarely in other hardwood species.
Bleeding	The process of diffusion of a coloured substance such as pitch from a knot through a paint or varnish coating, resulting in an undesirable staining or discolouration.
Blistering	The formation of dome-shaped projections in paints or varnish films by local loss of adhesion to the underlying surface and lifting of the film. Usually caused by applying paint to a surface containing excessive moisture. It may also be caused by excessive heat, or by using paint with poor adhesive qualities.
Board	A piece of lumber that is less than 38mm (2" nominal) in smaller dimension used for sheathing, formwork, or for further manufacture into trim and shaped products, such as siding.
Board Foot	A unit of measurement of lumber represented by a board 1 foot long, 12 inches wide, and 1 inch thick or its cubic equivalent. In areas where metric measure has been implemented, the cubic metre may be used to measure timber harvest, but "board foot" remains the unit of measure for lumber production and sale.
Bond Failure	Rupture of adhesive bond.
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Bond Strength	The unit load applied in tension, compression, flexure, cleavage, or shear, required to break an adhesive assembly, with failure occurring in or near the plane of the bond.
Bow	A deviation from a straight line (a curve along the face of the piece of lumber) from end to end of a piece, measured at the point of greatest deviation.
Box Beam	A built-up beam with solid wood flanges and plywood or woodbase panel product webs.
Brace, Lateral	A continuous member connected to a truss chord to maintain the vertical position of the truss during construction.
Brace, Vertical	Cross Members placed in a vertical plane between an X pattern between trusses to prevent rotation of the tops of the truss under load.
Broad-leaved trees	Trees which shed their leaves in the autumn. Most broadleaved or deciduous trees are hardwoods and have broad leaves.
Building Area	The greatest horizontal area of a building above grade within the outside surtace of exterior walls or within the outside surface of exterior walls and the centreline of firewalls.
Building Height	The number of storeys contained between the roof and the floor of the first storey.
Burl	Swirl or twist in wood grain usually occurring near a knot, valued as the source of highly-figured burl veneers used for ornamental purposes.
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