Glossary - Flooring Products

Above-Grade Level: A suspended floor located above the surface of the ground, over a well-ventilated air space with at least 18 inches between the bottom of the lowest horizontal structural member and any point of the ground. An above-grade subfloor is normally over a basement or a crawl space.

Abrasion Resistance: Resistance to a form of wear in which a gradual removal of a flooring surface is caused by the frictional action of relatively fine particles. Abrasion resistance generally depends on the toughness of the product or wear-layer, thickness of wear-layer, and existence of surface coatings.

Abrasion: Wearing, grinding, or rubbing away by friction

Acclimation: The act of allowing wood moisture content to become at equilibrium with the environment in which it will perform (See EMC, Equilibrium Moisture Content)

ACI: American Concrete Institute - a trade organization of the concrete industry.

Acid Etch: Refers to the use of a mixture of muriatic acid and water on concrete either to neutralize the surface if it shows signs of alkali or to open the surface to allow a good bond with adhesives or powder underlayments. This can actually cause problems in bonding due to acid residue.

Acid: Chemical substance rated below 7 on the pH scale

Acoustics: The sounds of floor traffic and dropped objects are important when considering types of flooring materials. The cushioning of impacts reduces the generation of airborne sound within the room and the level of sound that can be transmitted to adjacent areas. It also minimizes the transmission of impact-generated, structure-borne noises throughout the building. In multifamily dwellings, the transmission of impact-generated noise is of primary concern. Resilient flooring, in general, "give" under the impact of footsteps, dropped objects and rolling loads. The resilience helps to reduce traffic noise. In comparison with other hard-surfaced flooring (wood, marble, ceramic, concrete, metal), resilient floors are low noise producers.

Acrylic Resin: A synthetic resin usually white in color that dries transparent and is resistant to discoloration, moisture, alcohol, acids, alkalis and mineral oils. It is usually made by polymerization of acrylic acid and methacrylic acid.

Acrylic/Wood: The generic name for wood/plastic composites using wood impregnated with acrylic monomers and polymerized within the wood cells.

Addenda: The portion of an architect's specification that is added after the specification when a building project is written.

Adhesion: The property that causes one material to stick to another. Adhesion is affected by the condition of the surface to be coated and by the closeness of contact, as well as by the molecular forces of the unlike substances. Thus, the surface should allow a certain amount of penetration, should be chemically clean and not too smooth, hard or nonporous for good adhesion.

Adhesive Bleeding: Undesired migration of materials in the adhesive to the surface of the floor between tile joints.

Adhesive: A substance that is capable of holding materials together by surface attachment. Adhesive is also called cement, glue, mastic or paste.

Adsorption: A type of adhesion that occurs at the surface of a solid or liquid in contact with another medium, thus allowing an increased number of molecules of the gas or liquid to become attached to the surface of the solid at the point of contact.

Aggregate: Hard, inert material used in concrete. Fine aggregate is 1/4" or less in diameter and usually consists of sand. Coarse aggregate is 1/4" up to 1-1/2" in diameter and usually consists of crushed gravel.

AIA: American Institute of Architects - the largest organization of recognized architects in the United States.

Air Bubbles: Trapped air under flooring. Bubbles can be small or large in size. When bubbles appear shortly after installation, placing the flooring into the adhesive too soon or rolling improperly is generally the cause. When they appear at a later time, they may be caused by moisture in the subfloor.

Air Dried: Dried by exposure to air in a yard or shed without artificial heat. (Not kiln dried)

Air-Entrained Concrete: Concrete containing tiny air bubbles formed by adding soap-like resinous or fatty materials to the cement or to the concrete when mixed. Bubbles give the water in the concrete enough room to expand as it freezes.

Alkali: A soluble mineral salt present in some soil and natural water.

Alkaline Salts: Diluted salts that are carried to the surface of a concrete subfloor by water coming up from the ground below. These salts may cause installation failure of resilient flooring by destroying the adhesive bond. They can work their way up through tile joints and sheet goods' seams. In dry concrete, normal surface alkalinity on a pH scale is 9 or less. When alkali readings on a slab are above 9, alkali can cause problems with a flooring installation. There is no guarantee any treatment will keep the surface free of alkali, but washing the surface with clear water or soda water will lower the alkalinity. Traditionally, muriatic acid has been used, but it too may leave behind residue, which can adversely affect the flooring installation.

Alkalinity: A measurement of alkaline rated above 7 on the pH scale.

Alligatoring: A finish that exhibits large segmented cracks with the appearance of an alligator hide. May be caused by heavy coating, coating over non-cured coatings, use of fast drying thinners or the application of a finish over another with less elasticity.

Amber: A yellowish color change from either the wood or finish. See Color Change.

Aniline Colors: Colors made from aniline oils or coal tar derivatives, and used in the manufacture of wood stains. Aniline dyes are made in different grades to be soluble in water, alcohol or hydrocarbons, and accordingly are called water colors, spirit colors and oil colors, respectively.

Anisotropic: Not possessing the same properties in all directions. Wood is anisotropic because the shrinking and swelling, from moisture loss or gain, are unequal in length, thickness, and width

Annual Growth Ring: The layer of wood growth, including spring and summerwood, formed on a tree during a single growing season.

ANSI: American National Standards Institute.

APA Trademarked: Wood underlayments approved by APA - The Engineered Wood Association - as suitable for the installation of resilient flooring.

APA: The Engineered Wood Association, formally known as the American Plywood Association - A trade organization that specifies which wood panels are acceptable as underlayment boards for resilient flooring.

Applicator Marks or Streaks: Associated with partially cured finishes. When an applicator is drawn across the surface of half-set finish, especially when applying a new section of finish, the lapped area is deglossed leaving a streak. Usually caused by thin films, which have faster curing times than the surrounding area. May also be caused by inadequate agitation of satin and semi-gloss finishes, which allows "settling" of glossing agents.

Aqueous: A water-based solution or a solution containing water.

Armafelt: A moisture-resistant Armstrong felt backing that allows sheet flooring to be installed on all grade levels.

Armstrong Adhesive 57: A high solids, high strength urethane adhesive with no water. Used to install Armstrong hardwood flooring products except foam-tile. Various trowels are used for different flooring products. Available in 3 1/2 gallon sizes only.

Armstrong Adhesive Remover: A specially formulated solvent to remove Armstrong Adhesive 57. Available in one quart sizes only.

Ashlar: A method of installation of brick or tile flooring where the joints in one course (row) of the tile fall directly in the center of each tile in the rows of tile immediately adjacent.

Asphalt Saturated Felt Paper: A 15lb asphalt felt paper that meets ASTM Standard D 4869 or 30/30/30 Asphalt laminated Kraft paper that meets federal specification UU-13-790A commonly used to retard moisture.

ASTM: a.) American Society of Testing Materials - sets testing standards for a variety of materials including resilient flooring. b.) American Standard Testing Methods

Automatic Floor Machine: A self-contained, single- or multiple-disc floor machine that dispenses cleaning solution, scrubs the floor and takes up the spent solution in a single operation, leaving the floor clean and dry. Available in a variety of sizes, automatic floor machines can be equipped with either brushes or pads.

Backing: The bottom layer of the floor covering. This is the part of the flooring which determines what adhesive will be used for installation over various substrates.

Balling: Incapable of being troweled satisfactorily, the adhesive "balls up" under the trowel, and is usually due to a dusty or dirty substrate. May also occur when the adhesive has been frozen.

Base Shoe: A molding designed to be attached to baseboard molding to cover expansion space. It is the alternative to a quarter-round in profile.

Baseboard: The finished exposed board around the wall at the floor.

Bastard Sawn: See Rift Sawn.

Beam: A piece of timber, steel, stone or other material placed horizontally to support a load over an opening from post to post (column to column).

Bearing: Any characteristic part of a building (wall, column, etc.) that supports part of the weight of the structure. A wall is often spoken as a "bearing-wall" whenever it supports weight other than itself.

Below-Grade Level: Below ground level partially or completely below the surrounding ground level and in direct contact with the ground or with fill which is in direct contact with the ground. Presence of moisture is assumed, and the subfloor must be tested to determine the moisture level.

Beveled Edge: The chamfered or beveled edge of strip flooring, plank, block and parquet. See Eased Edge.

Beveled Edging: An edge material, normally vinyl or rubber, fastened in place to taper the edge of the floor covering to a lower level. Also called reducer strip.

Bid: The offer or proposal of any contractor to the architect, owner or general contractor to furnish material and/or labor for one or more parts of a building.

Binder: The composition of a plastic that contains the resin, plasticizer and stabilizer; whatever is not binder is filler.

BioStride: A breakthrough, patent-pending polymer that contains biobased, rapidly renewable ingredients. BioStride’s unique plant-based composition reduces the reliance on petroleum and fossil fuels.

Bleed Back: Most commonly associated with stains but may be caused by a slow drying finish system. Deep stain penetration, especially in spring wood, causes slow curing of the stain due to the absence of airflow and oxygen. When humidity rises or with the application of a finish the cell structure swells causing the stain to be squeezed out forming a small droplet on the surface of the floor or film. Wiping with a dry, white towel normally identifies the presence of the problem which can be prevented by buffing with a red or white pad.

Bleeding: a.) Undesired migration of materials in an adhesive to the surface of the floor between tile joints. May be caused by moisture in subfloor, not enough open time, too much adhesive, solvent removers in the subfloor, or the use of no-rinse strippers within the first two years of the installation.
b.) When the color of a stain or other coating material works up into succeeding coats, imparting to them a certain amount of color, it is said to bleed.

Blister: A raised spot on the surface of a floor similar in shape to a blister on human skin. How soon after installation a blister develops can help determine the cause. Blisters that occur within a few hours are usually due to a concentration of trapped air. Blisters that occur at a later time often indicate the presence of moisture in the substrate.

Blistering: The formation of bubbles or pimples on the surface of finished work. It is caused by exposure to excessive heat, grease or other volatile material under the finish, by moisture in the wood or by the too frequent application of coats. Anything that causes a gas or vapor to form under the film may cause blistering.

Blushing: The formation of a white or grayish cast in a spirit varnish, shellac or lacquer film during the drying period. It is caused by the partial or total precipitation of the solid ingredient as a result of condensed moisture in the film. This may be caused by excessive humidity or by use of an improper solvent.

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 practice, the board foot calculation for lumber 1 inch or more in thickness is based on its nominal thickness and width and the actual length. Lumber with a nominal thickness of less than 1 inch is calculated as 1 inch.

Boards: Manufactured from reconstituted wood particles as opposed to wafers or strands. Commonly referred to as flakeboard or chipboard, these panels are comprised of small particles usually arranged in layers by size.

Body: a.) Often used to describe the consistency of viscosity of a finishing material. It's also used to describe the fullness or thickness of film on the work. b.) The consistency of an adhesive.

Boiling Point: The temperature at which the vapor pressure of a liquid equals the air pressure, or the temperature at which a liquid begins to boil.

Bond Release: Part of the function of the polyethylene foam underlayment is to prevent the bonding of the laminate floor to the subfloor. Without a bond breaker, the glue pressed out of the bottom during the glue up step will adhere the floor to the subfloor.

Bond Test: A 72-hour test to determine if resilient flooring can be adhered to the subfloor with the recommended adhesive. The test determines whether the adhesive is compatible with the subfloor. It can also detect the presence of moisture. Bond testing determines the compatibility of adhesive with sealers, curing agents and other foreign matter and determines the necessity of their removal.

Bond: a.) The adherence of one material to another. b.) The adhesion between two dissimilar materials.

Borders: Simple or intricate designs which frame and customize a flooring installation.

Bow: The distortion of lumber in which there is a deviation, in a direction perpendicular to the flat face, from a straight line from end to end of the piece.

Bowing: A specific type of warping when a parquet slat or plank unit has a curvature from end to end, flat wise, from a straight line.

Brush Marks: Marks of the brush that remain in the dried film of a finishing material. They are caused by working the material after its solvents have evaporated to the point that the flowing power has been lost or by defects in formulation that prevent the material from leveling out after it has been brushed.

Brushability: The ease with which a material can be applied with a brush under practical conditions.

Bubbling: The appearance of bubbles in the film of finish while a finishing material is being applied. It is caused by any condition that causes air, vapors or gases to be trapped in the film while it's soft, but after it has hardened sufficiently to prevent the gas from escaping.

Build Coat: A finishing material, usually of a transparent nature, used over the sealer or color coats and under the finishing coats to increase the fullness of the finished work.

Burl: A swirl or twist of the grain of the wood that usually occurs near a knot, but doesn't contain a knot, commonly found in the stump of a tree and where limbs branch out from the tree.

Calendering: Taking the fused mass of vinyl from the mixer and placing it onto two, hot, large rotating rolls and allowing the mass to be squeezed into a thin sheet; similar to a dough roller.

Cantilevered: That portion of a structure which projects beyond its own support is cantilevered.

Carbide Tipped Saw Blades: Special cutting blades that are available for most power cutting tools.

Cement: Usually refers to a portland cement.

Cementitious: Having the properties of cement; being made of cement.

Chalk Line: Usually a cotton cord coated with chalk. The cord is pulled taunt and snapped to mark a straight line. The chalk line is used to align spots, screeds and tiles.

Chatter Marks: Slight indentations causing a ripple effect on the surface of a wood floor. They are usually caused by sanding machines that have out of balance drums, bad drive belts or foreign objects stuck to the wheels. The marks are most noticeable on gloss finishes, in direct light areas or at eye level.

Check: a.) A lengthwise separation of the wood that usually extends across the rings of annual growth and commonly results from stress set up in wood during air or kiln drying. b.) A rupture or opening along the grain of the wood developed during seasoning. Generally seen on the quartersawn face along a ray.

Checking: Similar to alligatoring, except that the finish is broken into smaller segments.

Chemical Foam: Blowing agent placed in a plastisol, and when heated it decomposes and creates air cells to make a foam; primarily used in "cushioned rotovinyl" residential structures.

Chemical Resistance: Resistance to softening, bleaching or discoloration from common chemicals that may be spilled on the floor. Chemical resistance is most dependent on the composition of the product, the existence and chemistry of the surface coating and the susceptibility of the seams to failure in chemical spills.

Chipboard: See particleboard.

Chipped Grain: An area in which pieces of wood have been pulled or chipped away from the surface during machining; also called torn grain.

Chipping: The condition that occurs when a dried film of finishing material separates from the underneath surface in the form of flakes or chips. It is usually caused by insufficient elasticity or improper adhesion to the base material.

Clamps: Devices used to pull together the first two or three rows of laminate boards. It is important to have these first rows straight and well bonded prior to completion of the laminate installation.

Cleaning: Removal of minor marks, dust, grit and other extraneous materials from a surface.

Cleat: A barbed fastener commonly used as a mechanical device to fasten hardwood flooring.

Closed Specification: An architect's specification for one manufacturer's material only.

Coated Nails: Nails which have been coated with a resin or other type of coating which gives the nails better staying power. This helps prevent the nails from working back up from the underlayment and causing what are commonly called nail-pops. Nail-pops cause bumps in the appearance of the finished flooring. Some coated nails cause staining of resilient flooring. A quick test should be run to determine the potential for staining.

Color Change: Visual changes in the color of the wood species caused by exposure to light, deprivation of light and air, or some chemical reaction.

Color Trials: Material could be graded as regulars or irregulars, except color range is beyond acceptable limits for either grade. Color Trial material is sold "as is" with no warranty. Color Trials will be sold as single rolls. This category will include Residential Rotogravure Sheet Flooring Products.

Colorfastness: Exposure to strong sunlight may affect the performance and appearance of some types of resilient floors by causing fading, shrinking or blistering. Armstrong commercial resilient floors are not recommended for outdoor installation.

Column: A vertical wood, steel, stone or concrete shaft, pillar or support, free-standing, supporting the portion of the structure above it.

Combination Base and Shoe: A dual purpose molding that is 2" high and extends out from the wall 3/4" at the toe and is 78" long. Prefinished or unfinished available.

Combustible: Having a flash point of 80-150 degrees F.

Commercial Flooring: Floors designed for installation in commercial settings such as schools, hospitals, public buildings and institutions. Also referred to as contract flooring.

Compression Set: a.) A phenomenon occurring in wood when wood tries to expand, due to moisture gain, but cannot because of some restraining force. When the same wood loses the moisture, it will shrink the same amount as a similar piece of wood. This phenomenon is why cracks in wood floors continue to widen with repeated mopping when the cracks are filled with dirt and cannot expand with moisture gain. b.) Caused when wood strips or parquet slats absorb excess moisture and expand so much that the cells along the edges of adjoining pieces in the floor are crushed. This causes them to lose resiliency and create cracks when the floor returns to its normal moisture content.

Compressive Strength: The ability of a material, such as concrete, to withstand loads. Compressive strength is measured in pounds per square inch (PSI). If the compressive strength is 3500 psi, it means the subject material will withstand a load up to 3500 pounds per square inch without breaking down.

Concrete Curing Compound: Compounds which are applied to new concrete to seal water in for curing. This makes it possible to get onto the concrete quickly. Traditionally, slabs were kept wet for curing by traditional means such as wet straw, burlap, plastic film, etc. This kept the concrete wet for the 28 day "wet cure" but did not allow for use of the slab during the curing period. Whenever curing agents have been used, a bond test should be run to determine the compatibility of the adhesive to the curing compounds. Curing compounds must be removed in areas where calcium chloride tests are being run. When moisture testing fails, curing agents need to be removed to allow the concrete to dry.

Concrete Curing: The process of keeping concrete moist for an extended period of time. Curing is necessary to insure proper hydration, and for strength and quality.

Concrete Hardener: Compounds or other materials designed to strengthen the surface of new concrete and improve the quality of old concrete. These do not normally cause any bonding problems with resilient flooring installations, but a bond test should be run.

Concrete Sealer: Sealers are normally a finish coating used to protect concrete floors from traffic and surface cleaning and should not be used when the slab is intended as a substrate for resilient flooring. Sealers are designed to prevent water and dirt from getting into the concrete from the surface and render the concrete less porous. Sealers may interfere with the bond adhesives, and a bond test should always be run.

Concrete: A mixture of Portland cement, water, fine aggregate and coarse aggregate. The concrete is bound together by the Portland cement and water paste which surrounds the aggregate and fills all the spaces between particles.

Conditioning: A required step in the installation of laminate floors. This insures that the laminate has equilibrated to the new environment thus minimizing the risk for peaked seams or bowed boards.

Conductive Flooring: A floor designed to carry off built-up static electricity and reduce the risk of explosion in potentially explosive environments.

Coniferous: See Softwoods.

Construction Joint: Joints in concrete which occur whenever concrete work is concluded for the day. They separate areas of concrete placed at different times. In slabs on grade, construction joints usually align with and function as control or isolation joints.

Contact Adhesive: An adhesive applied to both surfaces to be bonded and is allowed to dry to the touch. It bonds to itself instantaneously on contact. Since this type of adhesive does not remain tacky, it must not be allowed to dry.

Control or Contraction Joints: Joints in concrete which are grooved, formed or sawed into slabs so cracking will occur in these joints rather than in a random manner. They extend to 1/4 the depth of the concrete thickness. When the concrete is completely cured and dry, they may be filled with a Portland-based underlayment before the application of resilient flooring.

Conversion Varnish: See Swedish Finish.

Cove Base: Usually made of vinyl or rubber in a variety of sizes and shapes, cove base is designed to give a finished appearance between the floor and the wall. The base meets requirements of ASTM F 1861, Standard Specification for Resilient Wall Base.

Cove Stick: A stick made of wood, plastic or wax which is placed at the juncture of the floor and wall to support sheet flooring which is flash coved. If there is no support behind the cove, the flooring can be punctured.

Cove: A trim piece having one edge with a concave radius. A cove is used to form a junction between the bottom wall course and the floor.

Crazing: The appearance of minute, interlacing cracks or checks on the surface of a dried film of finishing material.

Crook: The distortion of a board in which there is a deviation, in a direction perpendicular to the edge, from a straight line from end to end of the piece.

Cross Direction: Laying of material perpendicular to the material below it.

Cross Pull: A condition occurring at an end joint with the ends of flooring strips pulled in opposite directions.

Crowfoot Checking: The name given to the defect when the breaks in the film form a definite three-prong pattern with the breaks running outward from a central point of intersection. When the checks are generally arranged in parallel lines, the defect is known as line checking. Irregular checks without a definite pattern are known as irregular checking.

Crowfooting: A species of crystallization (See Checking) wherein the lines come together at a central point.

Crowning: A convex or crowned condition or appearance of individual strips with the center of the strip higher than the edges. The opposite of cupping.

Cupping: A concave or dished appearance of individual strips with the edges raised above the center. The opposite of crowning.

Cure: To change the properties of a product by chemical action as opposed to drying when the product has reached its optimum state.

Curing: Process of keeping concrete moist for an extended period of time. Necessary to insure proper hydration and for strength and quality.

Cushioning: All laminated floor structures require the use of some kind of foam underlayment to be placed over the subfloor. These foam materials conform to minor subfloor imperfections and stop the "grinding" that would occur if the laminate floor structure were just placed directly on the subfloor.

Cut: To sand a floor. As a noun, cut refers to one pass over an area of floor with sanding equipment. Usually, a mechanic will make two or more cuts with progressively finer grits of sandpaper.

Cutback Adhesives: Refers to asphalt adhesives which have been liquefied with petroleum solvents. When the lighter fractions are boiled away from petroleum oil, the thick residue left is asphalt. To make it fluid again, solvent is added and the asphalt is "cut back."

Cutter: A term applied to a flooring unit that must be cut to fit next to a wall, or any vertical object, to allow for the proper expansion space between the flooring and all vertical objects.

Damp Mopping: This procedure involves the removal of fine dust, grit and spills from the floor surface with a mop dampened with a neutral detergent solution. Performed daily, this procedure helps to control grit and can reduce time and money spent on more intensive maintenance procedures.

Deciduous: See Hardwood.

Defect: Any abnormality lowering the value of a product no matter why, when, or how it developed.

Deflection: A variation in the position or shapes of a structure or structural element due to the effects of loads or volume change; usually measured as a linear deviation from an established plan rather than an angular variation.

Delamination: The separation of layers in an engineered/laminate through failure within the adhesive or at the bond between adhesive and laminate.

Diffuse/Porous Woods: Certain hardwoods in which the pores tend to be uniform in size and distribution throughout each annual ring or to decrease in size slightly and gradually toward the outer border of the annual growth ring. Hard maple is an example.

Dimensional Stability: The ability to maintain the original intended dimensions when influenced by a foreign substance. Wood is not dimensionally stable with changes in moisture content below the fiber saturation point. Engineered wood flooring, however, is more dimensionally stable than solid wood.

Dispersed: In reference to finishing materials, finely divided or colloidal in nature.

Distressed: A heavy artificial texture in which the floor has been scraped, scratched or gouged to give it a timeworn antique look. A common method of distressing is wire brushing.

Drier: A catalytic material that improves the drying or hardening properties of oils or varnishes when added in small amounts. They are usually organic salts of lead, cobalt, manganese, zinc and iron, such as naphthenates, resonates and linoleates.

Dry Fitting: A procedure where the first couple of rows of laminate floor are placed together, without glue, to get the proper orientation and starting point for the continuation of the remaining floor.

Dry Tack-Free: The stage of solidification of a film of finishing material when it doesn't feel sticky or tacky when a finger is drawn lightly across it in a quick continuous motion.

Dry to Sand: That stage of solidification of an applied film of finishing material when it can be sanded without undue softening, sticking or clogging of the sandpaper.

Dry to Touch: That stage of drying of a film of finishing material when it has solidified sufficiently that it can be touched lightly without any of the finishing material adhering to the fingers.

Drying: The act of changing from a liquid film to a solid film by the evaporation of solvents, oxidation, polymerization or by a combination of these phenomena.

Drywall: Interior covering material, such as gypsum board, hardboard or plywood, that is applied in large sheets or panels.

Durability: The ability of the wood species or finish to withstand the conditions or destructive agents with which it comes in contact in actual usage, without an appreciable change in appearance or other important properties.

Dust: Small particles of solid matter. Also, a grading or size of natural resin.

Dust-Free: That stage of solidification of an applied film of finishing material when dust that settles on the coated surface won't penetrate or stick to the film.

Dusting: Appearance of powdery material on the surface of newly hardened concrete. Sometimes caused by allowing the surface to dry too rapidly without curing.

Ease Of Cleaning: Most dependent on the porosity of the surface that provides voids for dirt entrapment, presence of surface coatings, uniform coverage of the coating, and toughness of the surface coating to stand-up to wear and maintenance routines.

Eased Edge: See Beveled Edge.

Easy Clean: A water based cleaner for use with all Armstrong Flooring.

Embossing: A permanent multilevel surface of flooring produced by mechanical or chemical means during manufacturing. Embossing provides a three-dimensional appearance and helps conceal subfloor irregularities. It also prolongs gloss retention because only the high points of the embossing receive surface abrasion.

End Joint: The place where two pieces of flooring are joined together end to end.

End-Matched: In tongue and groove strip and plank flooring, the individual pieces have a tongue milled on one end and a groove milled on the opposite end, so that when the individual strips or planks are butted together, the tongue of one piece fits into the groove of the next piece. See Side-Matched and Tongue and Grooved.

Engineered: An assembly made by bonding layers of veneer or lumber with an adhesive so that the adjacent layers have their grains going in opposite directions to increase dimensional stability.

Epoxy Adhesive: A very strong two-part thermo set adhesive which is mixed on the job. Depending on the use, epoxies can have short or long working times.

Epoxy, Epoxy Ester: A varnish that, with the addition of epoxy, creates a hybrid with the advantages of both products. Ambers well with quick build and high gloss but can be difficult to repair.

Equilibrium Moisture Content (EMC): The point of balance when the moisture content in wood is equal to the moisture content in the surrounding atmosphere.

Estimate: A preliminary cost figure prepared by contractors or others to give a job owner and/or architect a rough idea of the cost of a completed building

Expansion Joint Cover: Special covers designed to span expansion joints and move with the movement of the separate parts of concrete without breaking.

Expansion Joint: Separations between adjoining parts of a concrete slab allowing separate movement of the parts. They are usually filled with an elastomeric type of material. Expansion joints should never be filled with a cementitious underlayment product because any movement of the separate parts may cause the underlayment to break up and be pushed out of the joint. Resilient flooring should not be installed over this type of joint as cracking and buckling may occur. Expansion joint covers should be used instead.

Expansion Zone: An "air" space around the perimeter of a laminate floor structure which allows for growth and expansion of the floor due to changes in environmental conditions.

Fading: The loss of color due to exposure to light, heat or other destructive agents.

Feather Edge: The tapering of the edge of a film of dried material either by the method of application, sanding, or rubbing the dried film, resulting in a gradual progression of the film thickness from little or no material at the edge to a normal coating at the center.

Feature Strip: A strip of wood used at a threshold or to border a room or to otherwise serve as an accent. Usually of a contrasting color or species.

Federal Specifications: Standards which are established for various types of flooring by the General Services Administration (GSA) in Washington, D.C. Federal Specifications have been replaced by ASTM Standards.

Fiber Saturation Point (FSP): The stage in drying or wetting wood at which the cell walls are saturated with water and the cell cavities are free from water. It's usually taken as approximately 30 percent moisture content, based on oven dry weight.

Fiberboard: A broad generic term inclusive of sheet materials of widely varying densities manufactured of refined or partially refined wood or other vegetable fibers. Bonding agents and other materials may be added to increase strength, resistance to moisture, fire or decay, or to improve some other property.

Figure: Inherent markings, designs or configurations on the surface of the wood produced by the annual growth rings, rays, knots and deviations from regular grain.

Fill: Sand, gravel or dirt used to bring a subgrade up to desired level.

Filler: In woodworking, any substance used to fill the holes and irregularities in planed or sanded surfaces to decrease the porosity of the surface before applying finish coatings. Wood filler used for cracks, knotholes, worm holes, etc

Fillets: The small components which comprise parquet. Also called fingers or slats.

Finger-block: Parquet made from small strips of wood assembled together. See Fillets.

Fingers: See Fillets.

Fire Resistance: The property of a material or assembly to withstand fire or give protection from it. Certain wood species naturally provide greater fire resistance than others. Classes are I, II, III or A, B, C with Class I or A being the most fire resistant.

Fire Retardant: A chemical or preparation of chemicals used to reduce flammability or to retard the spread of a fire over a surface.

Fire Testing: Resilient floor coverings are usually exempt from model building code flammability requirements. However, some building code officials, government agencies and other regulatory authorities require test information on the fire performance of resilient flooring. The most widely used test for flammability is based on the Flooring Radiant Panel Test. The current editions of the B.O.C.A., Standard Building Code, and the NFPA 101 Life Safety Code reference the Flooring Radiant Panel Test. NOTE: Numerical flammability ratings alone may not define the performance of a product under actual fire conditions. Ratings are provided only for use in the selection of products to meet the specified limits. Flooring Radiant Panel Test - ASTM E 648 (NFPA Standard 253 and Federal Standard #372) - In this test, a horizontally mounted floor covering system is exposed to radiant energy from a gas/air fuel radiant panel mounted above one end of the sample and inclined at a 30 degree angle. The radiant panel gene

Fish Eyes: Also called cratering, crawling, holes, spots or flow marks. When caused by surface contaminants the finish is applied over areas in which the wetting agents cannot perform their function. The finish then recedes away from this area reforming into the film. This "crawling" creates round or elliptical areas lacking adequate finish. May also be caused by failing to properly agitate a finish prior to application. Without proper agitation, properties within the finish may separate. The flattening and wetting agents will therefore not be in proper concentration and cause this appearance.

Flag Worm Hole: One or more wormholes surrounded by a mineral streak.

Flag: A heavy dark mineral streak shaped like a banner.

Flame Spread: The propagation of a flame away from the source of ignition across the surface of a liquid or solid, or through the volume of a gaseous mixture. NOTE: Most wood species are Class C Flame Spread unless the wood floor has been treated and marked.

Flammable: Having a flash point of 20-80 degrees F.

Flash Coving: An extension of the sheet flooring up the wall a few inches to form a wall base integral with the flooring.

Flash Point: Temperature at which an inflammable liquid produces a vapor which, when mixed with air, becomes an explosive mixture.

Flatting Agent: A material added to a normally glossy coating to reduce luster and produce a flat appearance.

Flecks: The wide, irregular, conspicuous figure in quartersawn oak flooring. See Medullary Rays.

Flexibility: The degree of a floor covering material's ability to be bent, turned or twisted without cracking, breaking or showing other permanent damage. Flexibility will vary with temperature.

Floor Machine Brush: A circular brush with the bristles of varying stiffness and abrasiveness, depending on whether it's to be used for scrubbing, buffing or stripping. Bristles are made of natural or synthetic fibers or grit-impregnated nylon. Always follow flooring manufacturer's guidelines for choosing the floor machine brush with the appropriate stiffness and abrasiveness.

Floor Machine Pad: A non-woven nylon, polyester, or natural fiber disc up to 1" thick. Each disc has various types and sizes of intertwined fibers, some of which may have grit particles bound to the fiber surface. Coarseness of the pad determines its use: least coarse for buffing, with increasing coarseness for scrubbing and stripping. Pads are color-coded to designate their coarseness and use. Lighter-color pads tend to be less abrasive, with darker-color pads being the most abrasive. Pad manufacturer's generally follow these guidelines: 1. Natural fiber for burnishing; 2. White for polishing; 3. Beige for buffing; 4. Red for spray-buffing and light scrubbing; 5. Blue or green (medium abrasive) for scrubbing and stripping; 6. Brown or black (extremely abrasive). Armstrong does not recommend the use of brown or black pads on any of our resilient floors.

Floor Machine: A single-disc machine that can be equipped with either pads or brushes. It can be used for scrubbing, buffing and stripping.

Flow: The characteristic of a coating that allows it to level or spread into a smooth film of uniform thickness before hardening.

Footing: The spreading course or courses at the base or bottom of a foundation wall, pier or column.

Ford Cup: A type of viscosimeter originally used by the Ford Motor Company, but now used extensively in testing laboratories. It consists of a cup with an overflow device to ensure a standardized volume, in the bottom of which is a standardized orifice. The number of seconds required for the cup to empty itself at a standardized temperature gives a numerical expression of the viscosity of the material.

Foundation: The structural portion of a building or wall below the first floor construction, including the footings.

Framing: The rough timberwork of a structure including the walls, floors, roof, ceiling and the beams and studs which make up these various parts.

Freeze/Thaw Stable: An adhesive which is able to be frozen and thawed for a specified number of times without the emulsion breaking. When an adhesive is harmed by freezing, it is the handling characteristics which are affected. The adhesive becomes rubbery, stringy and thick, and is unable to be troweled or applied to the substrate.

Full Spread Installation: Spreading the adhesive over the entire substrate before placing the flooring.

Fuzzy Grain: Fibers protruding on the finished surface exhibiting a rough surface.

Gauge: The nominal thickness of a flooring material or of a layer within the material. With resilient flooring, wear layer and backing gauge are often listed separately.

General Contractor: The "prime contractor" or major contractor, who, under the architect, is the firm in charge of any construction. All subcontractors report to the general contractor except in those cases where the subcontract portion of the project is taken out of the general contract and led by the architect or owner directly. The general contractor is responsible for the completion of all portions of the project which fall under his supervision and bases his bid for all the work under his direction on the bids provided him by the subcontractors. A general contracting firm may do a number of the major items in the job, i.e. masonry, carpentry, etc., but most often asks for bids for the items included in his contract from a number of subcontractors.

Gloss Meter: An instrument for measuring the luster or gloss of a finished surface.

Gloss: The luster, shininess or reflecting ability of a surface.

Glossing Up: The increase of luster in a rubbed film through friction in use or the increase in luster of a flat varnish in the package through a decrease in the effect of a flattening agent.

Gouge: A groove or cavity in the flooring surface accompanied by material removal and penetration below the immediate flooring surface.

Grab: The property that enables an adhesive film to hold in place an adherent which is trying to pull away. This is usually applied to a partially set film.

Grade: The level of the subfloor in relation to the surrounding ground.

Grain: A general term describing the direction and alignment of the wood elements.

Graininess: The objectionable appearance of small, grain-like particles in a finishing material or in the dried film thereof.

Green Concrete: Concrete which is fairly new and has not had a chance to completely cure and/or dry.

Growth Rings: Increments of growth. Seen in a cross section of a log as rings around the center of the log. When only one growth ring is formed a year, it is called an annual ring. Viewing the end of a parquet slat, they appear in bands or layers.

Hardness: That property of the wood species or dried film of finishing material that causes it to withstand denting or being marked when pressure is exerted on its surface by an outside object or force.

Hardwood: Generally, one of the botanical groups of deciduous trees that have broad leaves, in contrast to the conifers or softwoods. The term has no reference to the actual hardness of the wood.

Heartwood: The inner portion of the log that dies. Its is generally darker in color than sapwood.

Heat-Welded Seam: A seam produced by grooving abutting edges of resilient flooring and filling the groove with heated, fused or melted material (usually from a weld rod) to provide a bond and seal. Excess welding material is trimmed flush with the finished flooring after cooling.

Heavy Streaks: Spots and streaks of sufficient size and density to severely mar the appearance of wood.

Heterogeneous Sheet Flooring: Floor surfacing in sheet form consisting of a wear layer and other layers which differ in composition and/or design and may contain a reinforcement. (Sometimes called layered composite or backed vinyl sheet flooring) The flooring meets requirements of ASTM F 1303, Standard Specification for Sheet Vinyl Floor Covering with Backing.

High Solids: A general term used to denote the presence of a higher than average percentage of solid ingredients and thus a lower percentage of solvents.

High-Speed Buffer: A floor machine designed for buffing and spray-buffing at speeds of 300 to 1100 rpm. (For machines in the 1100 to 2000 plus rpm range, see Ultra High-Speed buffer.)

Homogeneous Sheet Flooring: Floor surfacing in sheet form that is of uniform structure and composition throughout, usually consisting of vinyl plastic resins, plasticizers, fillers, pigments, and stabilizers. (Sometimes called unbacked vinyl sheet flooring.) The flooring meets requirements of ASTM F 1913, Standard Specification for Sheet Vinyl Floor Covering without Backing.

Honeycombing: a.) Checks often not visible at the surface that occur in the interior of a piece of wood, usually along the wood rays. b.) Large ruptures or openings along the grain in wood that develop during kiln drying due to internal stresses.

Hot-Melt Adhesive: An adhesive which is specially formulated and placed on the back of resilient tile so it can be installed without spreading any other adhesive products. This is normally used on tile commonly referred to as Place n Press, and is sold to the do-it-yourself (DIY) market.

Hot-Melt Calendering: New technology used to melt a vinyl wear-layer into the calender and immediately place it onto a calendered backing material for a composite structure.

Humidity: The amount of water vapor in the air. See Relative Humidity.

Hydration: The chemical reaction between water and Portland cement, which causes the concrete to attain its ultimate compressive strength.

Hydrostatic Pressure: Pressure which forces water up through a below-grade slab, generally causing installation problems due to moisture. This occurs when the water table is higher than the slab. Hydrostatic pressure is caused by the weight of the water pressing down on itself. Contrary to popular belief, this is not the cause of most problems with resilient flooring.

Hygrometer: An instrument for measuring the degree of humidity or relative humidity of the atmosphere.

Hygroscopic: a.) A substance that can absorb and retain moisture, or lose or throw off moisture. Wood and wood products are hygroscopic. They expand with absorption of moisture and their dimensions become smaller when moisture is lost or thrown off. b.) The ability to lose or gain moisture relative to the atmospheric humidity and temperature.

Impact Insulation Class: IIC is the measurement of how well a product resists the direct transfer of an impact, over a wide frequency range, from an elevated floor to the room below.

Impact Loads: Impact loads are momentary indentations like those produced from walking traffic. These impact pressures are high (often as much as several thousand pounds per square inch), and the smaller or sharper the impact area, the more damaging the indentation. NOTE: The extremely high forces exerted by high heels or spiked shoes (1,000 psi [70.3 kg/sq cm] or more) may visibly damage wood floors, resilient floorings, and other commercial floor coverings. See also Static Loads and Rolling Loads.

Impact Test: A test for determining the resistance to shattering of a dried film by dropping a weight onto the finish.

Incompatible: Not capable of being mixed together without impairing the original properties of the materials being mixed. Mixing incompatible materials usually results in a separation of solid particles, cloudiness or turbidity.

Inlaid Sheet Flooring: Floor surfacing material in which the decorative pattern or design is formed by color areas set into the surface. The design may or may not extend through to a backing.

Inorganic: Being or composed of something other than plant or animal (i.e. mineral); primarily relates to fillers being inorganic.

Inset: The cutting and placement of a design or motif, usually of contrasting colors, into the overall floor covering.

Intensity: The intensity of a color is its purity or degree of hue as seen by the eye.

Intumesce: To expand with heat to provide a low density film. The term is used in reference to certain fire retardant coatings.

Irregulars: One piece of Armstrong resilient flooring material that is down-graded from regulars to irregulars because of one or more defects of material workmanship. The defects are primarily visual and may not be of such a degree as to make the goods unusable material. This material is not covered under the Armstrong material warranty and is sold "as is".

Jamb: The side of a doorway, door frame or window.

Jointed Flooring: Strip flooring, generally birch, beech, hard maple, oak or pecan, manufactured with square edges, not side matched, but usually end matched.

Joints: The junction of precut surfaces butted together, such as tile or underlayment boards.

Joist: a.) A small timber to which the boards of a floor or the laths of a ceiling are nailed. Joists rest on the walls or on girders. b.) One of a series of parallel beams used to support floor or ceiling loads and supported in turn by larger beams, girders or bearing walls.

Kauri-Butanol Valve: A measure of the solvent power of petroleum thinners, expressed as the number of milliliters of the product under test required to cause cloudiness or turbidity in 20 grams of a solution of Kauri in butyl alcohol that has been prepared under standardized conditions.

Kiln: A chamber having controlled air flow, temperature and relative humidity for drying lumber, veneer and other wood products.

Kiln-Dried: Dried in a kiln with the use of artificial heat.

Knot: The portion of a branch or limb that has been surrounded by subsequent growth of the stem. The shape of the knot as it appears on a cut surface depends on the angle of the cut relative to the long axis of the knot. In hardwood flooring, small and pin knots aren't more than one-half inch in diameter. A sound knot is a knot cut approximately parallel to its long axis so that the exposed section is definitely elongated.

Knotholes: Voids produced by the dropping of knots from the wood in which they are originally embedded.

Lacquer: A finish containing nitrocellulose more often used as a sealer. The fast curing properties of this finish are created by using a solvent with a very low flash point which causes it to be very flammable. Ambers little, cures rapidly, but may water spot and become cloudy when applied in high humidity.

Laminate: A composition of MDF board and multiple layers of impregnated papers and Aluminum Oxide.

Lap: a.) Used as a verb, lap means to lay or place one coat so its edge extends over and covers the edge of a previous coat, causing an increased thickness where the two coats are present, as compared to the single thickness on either side of the lap. b.) As a noun, lap is that portion of a coat of finishing material that extends over the edge of and onto a previous coat.

Latex: A milky, rubbery fluid found in several seed plants. Originally, latex meant the natural rubber dispersion as it came from the tree. Today, it includes synthetic rubbers or other polymers dispersed in water.

Layout Lines: Lines chalked on a substrate to guide in accurately setting tile.

LEED (Leadership in Energy and Environmental Design®): A green building rating system that was developed by the U.S. Green Building Council in 2000 through a consensus based process. LEED is a tool for buildings of all types and size. LEED certification offers third party validation of a project’s environmental features and verifies that the building is operating exactly the way it was designed to.

Legs: Long strings of adhesive developed between the flooring and the substrate as a result of the water evaporating or migrating from the adhesive. This is normally seen in rubber-based adhesives and is a desirable characteristic. It is important to remember that not all adhesives have legs and legs are not a necessary characteristic for good adhesion to occur.

Level: A surface or line with all points at the same elevation. Horizontally straight.

Leveling: The ability of a film to flow out free of ripples, pock marks, brush marks or other surface defects.

Light Reflectance: Brightness and quality of light play an important role in the illumination of institutional, commercial and industrial facilities. The light reflectivity ratings of resilient floors are important when taking the complete interior environment into consideration. Since a majority of resilient floors are made of combinations of different colors, these light reflectance figures are average values based on a large area of the pattern. (Light reflectivity values are determined by measuring the percentage of light directed at any surface that is then reflected under standardized test conditions.) The Illuminating Engineering Society of North America recommends that floors have a reflectance factor of 20% to 40% for optimal seeing areas in offices, 30% to 50% for school classrooms, and 20% to 30% for hospital operating rooms. Light reflectance should not be confused with gloss. Gloss can result in reflected glare from highly polished surfaces in the field of view. While gloss level depends primaril

Light Reflectivity: The Characteristics of a material which determines the degree or amount of light which will be reflected from its surface from any given angle.

Lightweight Concrete: Can be made two ways; may use lightweight aggregate such as shale, clays, pumice, etc. or may add chemicals that foam and produce air spaces in the concrete as it hardens.

Linoleum "Bloom": Linoleum "seasoning bloom" (also known as drying room film) is a natural phenomenon caused by the properties of the desiccant oils. These produce a yellow film that forms on the linoleum during the drying process. Any change in the product's appearance because of this film is temporary and disappears when the flooring is exposed to light. The time required for seasoning bloom to disappear ranges from several hours to several weeks depending on the light source's intensity. The light exposure process that eliminates the film will continue even after protective floor polishes are applied, although polish may slow the process. On areas of linoleum not exposed to light, elimination of the yellow film will not occur.

Linoleum: A surfacing material composed of a solidified mixture of linseed oil, pine rosin, fossil or other resins or rosins, or an equivalent oxidized oleoresinous binder, ground cork, wood flour, mineral fillers, and pigments bonded to a burlap, jute or other suitable backing.

Loosened Grain: The separation of the growth ring, primarily at the tips, from the surface of a wood slat, especially on the surface of plainsawn wood.

Manufacturing Defects: Includes all defects or blemishes that are produced in manufacturing, such as chipped grain, torn grain, skips in dressing, hit and miss (a series of surfaced areas with skips between them), variation in machining, machine burn, and mismatching.

Mastic: Relating to flooring adhesive and sometimes even to latex primers. It is normally associated with water-based products and is a catchall term.

Mechanic: A term used for a floor installer in the wood flooring industry.

Medullary Rays: Strips of cells extending radially within a tree. The rays serve primarily to store food and transport it through the tree. In some hardwood species, the rays form a conspicuous figure sometimes referred to as flecks. See Flecks.

Milk: Refers to a latex liquid used to prime dusty substrates or mix with an underlayment powder.

Milky: Having the appearance of milk or showing some whiteness, as when water is mixed with varnish or when a dried transparent film starts to turn white from moisture.

Mineral Spirits: A solvent product used as a thinner and/or cleaner.

Mineral Streak: a.) A general term used to describe discoloring in hardwoods. The discoloring ranges from greenish brown to black and has a high mineral content; also called mineral stain. b.) Wood containing an accumulation of mineral matter introduced by sap flow, causing an unnatural color ranging from greenish brown to black.

Mitered Corners: Usually, a 45 degree angle cut in the laminate to create custom borders and insets. These cuts require that a new groove be cut and a spline inserted prior to final installation.

Mixed Media: A wood floor that is predominately of wood, but also incorporates other materials, such as slate, stone, ceramic, marble or metal.

Moisture Content (MC): The amount of moisture in wood expressed as a percentage of the weight of oven dried wood. Most hardwood flooring is manufactured at 6 to 9 percent moisture content.

Moisture Resistance: Three types of moisture conditions may exist which will forewarn of possible moisture problems: 1. Concrete floor moisture - Concrete floors directly in contact with the ground are never completely dry. Also, the moisture content of new concrete is high, regardless of grade levels. Resilient floors may be seriously affected when installed directly over wet concrete which is not sufficiently dry. 2. Wood floor moisture - Wherever a wood floor is constructed over an inadequately ventilated crawl space, resilient floors are not recommended. Crawl spaces must be at least 18 in. (45.72 cm) high and cross-ventilated. Wood floors constructed on sleepers directly over concrete slabs are susceptible to moisture penetration. Such moisture is trapped under the resilient flooring, resulting in deterioration of wood fiber. For this reason, resilient floors are not recommended for installation over this type of subfloor. 3. Surface moisture - Resilient floors may be installed in areas where excessi

Moisture Vapor Barrier: Usually a polyethylene film used to impede or block the transmission of water from the subfloor up to the laminate structure.

Moisture-Cured Urethane: A finish that properly cures in the presence of moisture. It is very stain, spot and water resistant, but requires very tight environmental control during application and curing. May cure too rapidly and flatten poorly when applied in very high humidity. Long delays in curing may occur in areas when humidity levels are quite low. The finish has an excellent abrasion resistance which also makes it difficult to recoat.

Moldings: Accessory items that are used to enhance the appearance and performance of Armstrong floors. Six different moldings are available: reducer strip, threshold, quarter round, stair nosing,combination base and shoe and T-Molding. For 3/4" solid strip: reducer strip, stair nosing, and quarter round. See individual moldings for sizes.

Monolithic: Placed in one continuous pour without construction joints.

Mosaic Parquet: See Parquet.

Muratic Acid: A diluted acid used to neutralize alkalinity of concrete subfloors.

Net Seam: A net seam results from the proper setting of an underscriber and angle of the knife blade. If the blade is held at a true 90 degree angle to the floor, a net seam will result. Tilting the blade away from the edge will result in an open seam, while tilting toward the edge produces a too-tight seam.

Neutral Cleaner: A mild (pH of 6 to 8) detergent that does not contain any strongly alkaline materials, and is designed to remove soil, not floor polish.

Nominal Size: As applied to timber or lumber, the size by which it is known and sold in the market; often different from actual size.

Nonvolatile: That portion of a material which doesn't evaporate at ordinary temperatures; the solid substances left behind after the volatiles have evaporated.

Nosing: A hardwood molding used to cover the outside corner of a step, milled to meet the hardwood floor in the horizontal plane and to meet the riser in the vertical plane. It is usually used on landings.

Odor: That property of a substance which is perceptible by the sense of smell; the smell, scent or fragrance of a material.

Oil-Modified Urethane: An oil based varnish enhanced with urethane. This hybrid ambers well and has good abrasion resistance. Curing may be delayed when humidity levels are high. This finish is very stain and abrasion resistant, but has a long curing time.

On Grade: At ground level or in direct contact with the ground, over fill which is in direct contact with the ground, or with less then 18" of well-ventilated space between the bottom of the lowest horizontal structural member and any point of the ground. This is normally a floor which is on ground level with no basement or crawlspace beneath.

Open Grain (finish): failure of finish to form a film over areas of low density, normally associated with the softer spring wood. The finish is absorbed into the softer grain failing to form a film and causing a loss of sheen. While not considered a finish defect it can often be concealed by the application of an additional coat of finish.

Open Specification: This is a specification where the architect's requirements for material are stated but in which no specific manufacturer's product is listed. When a specification of this kind is written, the architect and/or the owner must approve material made by one or several manufacturers and then bids are made on the basis of the architect's approval of this material.

Open Time: Amount of time recommended for the adhesive to set before it is covered with the flooring. Open time is affected by temperature, humidity, and porosity of the substrate.

Orange Peel: A finish that exhibits a surface texture resembling the surface of an orange. Normally caused by rolling a finish that has cured excessively which freezes the roller pattern in the film. May also be caused by excessive airflow, the velocity of which freezes waves in the film when it sets.

Or-Equal Specification: An open-end specification where an architect will mention one or more manufacturers' products and will add the words "or equal". Those manufacturer's names given have had the architect's approval for this specification, but other competing products may be approved if the architect will recognize them as equal in quality and type to those specifically mentioned by name.

Organic: Having been living at one time (like petroleum, crude oil, coal, wood, etc.) or derived from living materials and/or containing carbon and hydrogen atoms; primarily relates to plastics being derived from petroleum.

OSB: Oriented Strand Board panels are constructed of strand-like wood particles arranged in layers (usually 3-5) oriented at right angles to each other. No longer used as an underlayment board although it is still available as STURD-I-FLOOR.

Overwood: A term used to describe a condition when adjoining edges of the flooring pieces are not the same height after installation is complete. Tolerances for each product and grade vary. May be called underwood.

Oxidation: The combination of a substance with oxygen.

Parquet Flooring Square: Basically a "tile" composed of individual slats held in place by a mechanical fastening. It is 6" x 6" and possesses interlocking tongues and grooves. May have either 7 or 8 slats per tile.

Parquet Flooring Unit: A 12" x 12" unit consisting of four squares or "tiles" fastened together.

Parquet: A tile composed of individual slats assembled together. A square may or may not possess tongues and grooves to interlock, and isn't necessarily square or regular in dimension.

Particleboard: Boards manufactured from reconstituted wood particles as opposed to wafers or strands. Commonly referred to as flakeboard or chipboard, these panels are comprised of small particles usually arranged in layers by size.

Parting Agent: Compounds used on wood or steel formwork for concrete to make it easier to remove the cured concrete from the form. Parting agents are normally silicone or paraffin waxes and must be removed before installation of resilient flooring.

Peaked Seams: A condition that can occur at the joints between two pieces of laminate that can be caused by too much moisture from the surface or from damage of the tongue during installation.

Peeling: A defect in a dried film manifested by large pieces becoming detached from the under surface and coming loose in sheets or large flakes.

Penetrating Stains: Stains that penetrate into the surface of the wood. They are usually made of dyes dissolved into liquids that easily penetrate the wood.

Permion® Finish: An Ultra Violet-cured urthane topcoat with aluminum and mineral oxide additives incorporated in the urethane. The oxides increase wearability of the urethane finishes.

Petroleum Spirits: Another name for mineral spirits.

pH Value: The concentration of the hydrogen ion in a material. A pH value of 7 is considered neutral. Lower values are acidic; higher values are alkaline.

Photo sensitive: The property of some wood species which causes them to lighten or darken when exposed to light. See Color Change.

Pigment Stains: Stains that get their color primarily from pigments mixed with binder and volatile thinners.

Pigment: The fine, solid particles used for color or other properties in the manufacture of paint, enamel and certain stains.

Pin Holes, Pin Lines (finish): Normally caused by finish flowing into low lying or less dense areas such as spring wood. This thicker film of finish allows gasses formed during curing to freeze in the film leaving a small crater. The finish fails to form a film in these areas as the finish is in the wood instead of on it. While not considered a finish defect it can often be corrected by the application of an additional coat of finish.

Pin Worm Hole: In hardwood flooring, a small round hole not more than 1/16inch (1.5626MM) in diameter, made by a small wood boring insect.

Pin Holes: Small round holes (1/100 to 1/4 inch in diameter) in wood that results from the mining of ambrosia and similar beetles.

Pith: The small, soft core occurring near the center of a tree trunk, branch, twig or log.

Plain Sawn: The annual growth rings make an angle of less than 45 degrees with the surface of the piece. This exposes the pores of the springwood and dense summerwood of the annual growth ring in ring porous woods to produce a pronounced grain pattern.

Plainsawn Wood: Wood that has been sawed from the hardwood log in such a manner so the growth rings form an angle from 00 to 450 with the surface.

Plan: A drawing representing a projection of any one of the floors or horizontal cross sections of a building or of the horizontal plane of any object or area.

Planer Bite: A groove cut in the surface of the edge of a parquet slat or on the face of a 3/4" solid strip, deeper than intended by the planer knives.

Plank: Solid or Engineered/Laminated boards 3" and wider designed to be installed in parallel rows. Edges may be beveled to simulate the appearance of Colonial American plank floors.

Plasticizer: Special oils developed to impart flexibility and special properties like stain resistance to plastics, like PVC; they are added in the compounding step to the vinyl resin. The most common plasticizer used in vinyl is called DOP short for, dioctyl phthalate (pronounced "die-octil-thal-ate").

Plasticizer Migration: The migration of the plasticizer in the flooring to the adhesive. This causes unwanted softening of the adhesive and may lead to release of the bond.

Plastisol: Made from a special kind of vinyl resin which is suspended in plasticizer and stabilizer to make it pourable as a liquid for coating purposes.

Plugs: Dowels that simulate the Colonial American plugged or pegged plank look. They are used to cover countersunk screws when installing wood flooring or for decorative purposes in wood flooring.

Plywood: A fabricated wood board made of three or more separate plies or panels of wood veneer laid with grain of adjoining plies at right angles. The most dimensionally stable of wood underlayment boards, plywood is recommended for all applications of resilient flooring. Standards for acceptable underlayments for resilient floors are set by the APA - The Engineered Wood Association.

Polish: A temporary coating that enhances the appearance and protects the substrate to which it is applied.

Polishing: The application of a temporary coating that protects the floor from wear, abrasion, soiling and discoloration, while smoothing the surface and significantly improving gloss. Polishes are easily removed and replaced or refurbished.

Polyurethane: A large molecule of chemically joined urethane units, having the capacity to solidify or "set". Irreversible when acted upon by heat, radiation or chemical cross-linking or curing agents. See Urethane.

Pores: Small straw-like ends of hardwood elements appearing on the ends of a slat or flooring unit as small holes. They are very predominant in the springwood of red oak.

Porosity: A matter which is porous or contains pores which are able to absorb liquid. Subfloors, which are porous, are normally concrete and wood. If there is any doubt as to the porosity of a subfloor, put a few drops of water on the surface. If the water is quickly absorbed, the surface is porous. If the water remains on the surface, the surface is nonporous.

Portland Cement: A finely pulverized material used in the making of concrete. When mixed with water, it causes hydration to occur. Named for its color - like the Isle of Port off the English coast.

Pot Life: The amount of time an adhesive remains useable in the container once it has been mixed or opened. Normally used in reference to products which are mixed together such as epoxy adhesives or portland-based underlayments.

Powdering: Partial or total disintegration of the polish film, resulting in a fine, light-colored material.

Pre-consumer recycled material: Manufacturing waste material, otherwise destined for a landfill, that has been reclaimed and used in a different product’s manufacturing process. Also called post-industrial recycled material.

Pre-finished: Factory finished flooring that only requires installation.

Printed Sheet Vinyl Flooring: A floor surfacing material which has a pattern printed on a backing and is protected with a wear layer of transparent or translucent vinyl plastic. Also called rotogravure sheet vinyl flooring.

Puckering: The crinkling, shriveling or wrinkling of a coat of finishing material upon drying.

Quantity: The amount, bulk, mass, weight or measure of a thing; a measure of its size or numbers.

Quarter Round: A molding, small in size, with the profile of a quarter circle. Frequently used as base molding for resilient flooring.

Quartersawn: The annual growth rings of wood form an angle of 45 degrees to 90 degrees with the surface of the piece. In quartersawn strips, the medullary rays or pith rays in ring porous woods are exposed as flecks that are reflective and produce a distinctive grain pattern.

Quartersawn Wood: Wood that has been sawed from a hardwood log in such a manner so the growth rings form an angle from 45° to 90° with the surface.

Quicklink 60 Adhesive: A polymeric resin based adhesive containing water that is used to install all Armstrong hardwood flooring products except Foam Tile. Various trowels are used for different flooring products. Available in 1 gallon and 4 gallon containers.

Radiant-Heated Subfloor: A subfloor which also serves as a means to heat an area. Generally, heating coils, pipes or ducts are built into the subfloor. All Armstrong resilient flooring may be installed over radiant-heated subfloors as long as the surface temperature does not exceed 85° F. When temperatures exceed this limit, the flooring can soften and increase the risk of indentation.

Raised Grain: A roughened or fuzzy condition of the face of the flooring in which the dense summerwood is raised above the softer springwood but not torn or separated.

Ramp: An inclined plane connecting two different levels and used instead of steps, elevators or conveyors.

Rapidly Renewable: Armstrong uses the USGBC LEED definition – “Material considered to be an agricultural product, both fiber and animal, that takes 10 years or less to grow or raise, and to harvest in an ongoing and sustainable fashion.” Source: USGBC Leed-NC version 2.2 reference guide.

Raw Materials: The natural, untreated or unprocessed materials from which varnishes or other coatings are made.

Ray Fleck: A part of a ray appearing very distinctly on the face of a quartersawn slat.

Ray: Tissue formed in a living tree that radiates from the pith towards the perimeter of a tree across the growth rings. Rays are very distinct in the oak species.

Rays, Wood: See Medullary Rays.

Reagent Stain Resistance: Resistance to color change/residue by common chemicals that floors are exposed to in specific end-use areas, like Betadine in hospital operating rooms, tempera paint in schools, or coffee in other areas. Reagent stain resistance is primarily a surface characteristic. It is most dependent upon the existence of surface coatings and the chemistry of the coatings.

Recoatability: The application characteristics of a polish and the appearance of the film after successive coatings to a surface.

Reduce: To lower the viscosity of a material or to thin it by the addition of a solvent, thinner, varnish, oil, etc.

Reducer Strip: A teardrop shaped molding accessory for hardwood flooring, normally used at doorways, but sometimes at fireplaces and as a room divider. It is grooved on one edge and tapered or feathered on the other edge.

Refinish: Sanding a previously finished floor to bare wood and applying new finish.

Regulars: One piece of Armstrong resilient flooring material that is free from manufacturing defect in material and workmanship. This material is covered under Armstrong's material warranty.

Reinforced Concrete: Made by casting concrete around steel rods or bars.

Relative Humidity: Ratio of the amount of water vapor present in the air to that which the air would hold at saturation at the same temperature. It is usually considered on the basis of the weight of the vapor, but for accuracy should be considered on the basis of vapor pressures.

Resilience: Resilience is a property involving the elastic energy in a material, which causes it to regain its original shape after having been indented by a high pressure load. Resilience, in its broadest sense, consists of properties beyond recovery from indentation.

Resiliency: The ability of a material to resume it's former shape after mechanical deformation.

Resilient Floor: A non-textile floor surfacing material made in sheet or tile form or formed in place. Materials include but are not limited to asphalt, cork, linoleum, rubber, vinyl, vinyl composition, and poured polymeric systems.

Retarder: A slowly evaporating solvent that decreases the evaporation rate or slows up the drying of lacquers and similar materials.

Ridging: Small, tunnel-like raised areas over underlayment joints. They are approximately 1/4" wide and similar in cause to tunnels.

Rift Sawn: Lumber (primarily hardwoods) in which the annual rings make angles of 30 degrees to 60 degrees with the surface of the piece. Also known as bastard sawn.

Ring Porous Woods: A group of hardwoods in which the pores are comparatively large at the beginning of each annual growth ring and decrease in size, more or less abruptly, toward the outer portion of the annual growth ring. The large pores are springwood and the smaller pores are summerwood.

Ring Shank Nail: Headed nail for underlayment installation with rings on the shaft (shank) to improve the holding characteristics.

Rolling Loads: Initial 72 Hours: Newly installed flooring should not be exposed to routine rolling traffic (carts, litters, gurneys, etc.) for at least 72 hours after installation to allow setting and drying of adhesives. Initial 72 Hours and Thereafter: The bearing surface area of wheels is deceptively small, resulting in higher compressive forces than may be anticipated. Therefore, when moving heavy fixtures or appliances over resilient flooring on casters or dollies, the flooring should be protected with 1/4 in. (6.35 mm) or thicker plywood, hardboard or other underlayment panels.

Rolling: When recommended, roll in one direction and then roll in the cross direction. Rolling should be done immediately after placing the flooring into the adhesive. Start at the center of the sheet flooring and work outward to move trapped air to the edges. Rolling flattens adhesive ridges and pushes the flooring into the adhesive for a better bond.

Router Bit: A cutting tool, used with a hand held or table mounted router to cut a new groove into a cut piece of laminate.

Sapwood: The wood near the outside of a tree.  It is usually lighter in color than heartwood.

Sawn:  See Plain Sawn, Quatersawn and Rift Sawn.

Sacrify:  A mechanical means of roughing a surface to abtain a better bond.

Scratch:  A shallow cut or narrow groove in the flooring surface.  A line or furrow made in the flooring surface by rasping or rubbing with a pointed or jagged object.

Scratches:  Slight incisions, breaks, tears or indentations ont he surface casued by abrasive friction.

Screeds:  Usually a 2"x4" (50MM x 100MM) pieceo f wood laid flat side down and attached to a concrete subfloor to provide a nailing surface for tongue and groove strip flooring or a wood subfloor.

Scrubbing: Washing a floor by wetting it with detergent solution, then using a moderately abrasive non-woven pad or appropriate brush, either by hand or attached to a low-speed floor machine, to vigorously agitate the wet surface. This procedure is used when a floor is heavily soiled, and less-aggressive cleaning methods have been unsuccessful. Always rinse thoroughly after scrubbing.

Scuff: A wearing away of the surface through abrasion or a thermo-mechanical displacement of the upper surface of the floor covering by friction from traffic bodies.

Scuffing Of Polish: Disfigurement of polish film resulting from an abrading or scraping action which is usually repairable without recoating.

Scuffing Of Resilient Flooring: A wearing away of the surface through abrasion or a thermo-mechanical displacement of the upper surface of the floor covering by friction from traffic bodies.

Sealer: Any finishing material that is applied with the primary purpose of stopping the absorption of succeeding coats.

Sealer-Wax Finishes: A combination of a sealer, generally varnish, with wax. Both the sealer and wax are normally burnished to enhance wear and appearance. Water spots an