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Glossary of Flooring Terms

Glossary of Flooring Terms

Become a flooring expert by learning the insider terminology! 



Above Grade
Refers to flooring installed above ground level, with a minimum of 18 inches of well-ventilated space available. 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
Refers to the act of wearing away at a hardwood floor finish 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.

The act of allowing wood moisture content to become at equilibrium with the environment in which it will perform (See EMC, Equilibrium Moisture Content). Refers to the hardwood’s adjustment to the environment it is in, in terms of moisture and humidity. Some hardwoods require an acclimation period of 4-5 days up to 2-3 weeks.

The properties or qualities of a room or building that determine how sounds are transmitted in it. In terms of flooring, the sounds of floor traffic and dropped objects are important considerations. 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.

Composed of synthetic resins and textile fibers and made from polymers of acrylic acid or acrylates.

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


Baby Threshold
Refers to a type of molding used in areas where expansion is needed, such as by sliding glass doors and to transition to carpet.

Refers to the molding installed at the base of a wall designed to cover a portion of the wall and floor. Multiple profiles and styles are available. A molding designed to be attached to baseboard molding to cover expansion space.

BCF Fiber
BCF stands for bulked continuous filament, and it refers to the length of the fibers used to make the carpet, and how it is manufactured. Unlike shorter staple fibers, BCF fibers are woven continuously through the carpet backing.

The term Berber commonly refers to a style of carpet that is made of looped fibers, but in technical terms, Berber actually refers to carpet that has a fleck of another color running through it.

Beveled Edge
Refers to a type of edge available in hardwood flooring. With a distinct and deep “v” shaped groove, the beveled edge hardwood is commonly used in informal settings. Also used where subflooring imperfections exist, as it helps to conceal them as well as slight differences in plank thicknesses.

A strip sewn over a carpet edge for protection against unraveling. Carpet is bound to form rugs.

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.

The term broadloom refers to carpets hand-woven on a loom, and literally means “wide loom”, meaning that the carpet was made on a large roll instead of a smaller area rug. Most commonly manufactured in 12’,13’2”, or 15’ widths.


Carpet Pile
Fibers that form the upper surface of carpet.

Carpet Tile
Carpet tiles are square sections of carpeting that are sometimes used in place of rolled carpeting. Available in a variety of designs and styles, these simple carpet squares make the process of installing carpeting in a room much less messy and complicated. Along with easy installation, the tiles also can be replaced easily.

Ceramic Tile
A tile made from clay that has been permanently hardened by heat, often having a decorative glaze.

Chatter Marks
Refers to patterned markings on the floor caused by the use of a drum sander.

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.

Cork flooring is a flooring material made from the bark from cork oak trees. Due to the natural insulation and water resilience of cork flooring it is suitable for commercial and residential use in all rooms and situations.

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.

Cross-Ply Construction
Refers to engineered hardwood planks stacked on top of each other, in alternating directions, creating dimensionally stable flooring less affected by moisture and changes in humidity.

A concave or dished appearance of individual strips with the edges raised above the center. The opposite of crowning. Warping where the sides are higher than the center.

Cut and Loop
Cut and loop is a style of carpet made by using a combination of looped fibers and cut fibers. The taller loops are sheared creating a sculptured pattern. The texture and often subtle, variegated coloring helps hide soil and traffic wear.


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

The term density is one of the most misunderstood and misused carpet terms. Often confused with face weight, density is actually representative of how close together the fibers are stitched into the carpet backing. It is calculated using a specific formula.

Dimensional Stability
The ability of the hardwood to retain its dimensions throughout its lifetime, avoiding warping, swelling and contracting in response to moisture and changes in temperature and humidity.High dimensional stability means the floor does not significantly warp, shrink or expand due to environmental changes.



End Cap/Molding
See “Baby Threshold”.

Engineered Hardwood
Wood made of a thin layer of solid hardwood glued or laminated onto a core board such as plywood or high density fiberboard to make the planks of flooring. Due to its construction, engineered hardwood is more dimensionally stable than solid hardwood and can be installed below grade and over a concrete subfloor.

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.

Expansion Gap
Area of perimeter left to account for expansion.


Face Weight
As mentioned above, face weight is often confused with the density of a carpet. Face weight is literally the weight of the carpet pile (not including the backing) per square yard. Face weight is very overused in the carpet industry and often abused by salespeople as an easy way to lead customers to believe they are getting a higher quality carpet.

Flat Weave
Flat weave rugs and carpets are flat woven items traditional to India, made of cotton or silk. They are noted for soft colorations and varied patterns.

Floating Floor
A type of installation that does not require the flooring to be attached to the subfloor.

Flush Reducer
Used to level the height between a wood floor and another floor surface to transition from room to room.

Flush Stair Nose
Allows a smooth transition between the stair edge and the riser.

A popular style of carpet, frieze is sometimes referred to as a twist or even a shag carpet. Friezes feature long lengths of fibers that are tightly twisted together, causing them to curl slightly. It is typically very durable and suitable for many uses.


Glazed Tile
Clay shaped in to tiles, fire-hardened, and then covered with a matte or glossy glaze to make the tiles more resistant to moisture.

Glueless Click-Lock
Refers to a very easy do-it-yourself installation of engineered hardwood flooring. No glue is required to install the floor because everything “clicks” and “locks” into place.


Hand Scraped Hardwood
Historically, floors were hand scraped on site to make the floors flat. Today’s hand scraping is usually done at the factory to give the floor an antique or vintage look. A truly hand-scraped floor will be unique – no two hand-scraped floors will look the same.

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.

HEPA Filter
High-efficiency particulate air (HEPA), also known as high-efficiency particulate air, is an efficiency standard of an air filter. Filters meeting the HEPA standards must satisfy certain levels of efficiency. Common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95%. HEPA filters are used in applications that require contamination control, such as the manufacturing of disk drives, medical devices, semiconductors, nuclear, food and pharmaceutical products, as well as in hospitals, homes, and vehicles.

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.

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.



Technique involving laying multiple pieces down to create a pattern inside the hardwood. For example, a border or a mosaic.


Janka Hardness
Refers to the strength of the hardwood material based on a scale which determines the amount of force it takes to drive a .444 inch steel ball into a plank of wood .222 inches in diameter.

An organic plant fiber made from the stems of a tropical Old World plant, used for making twine and rope or woven into sacking or matting.


Kiln Dried
Wood dried with artificial heat in a controlled environment as opposed to naturally air dried.


A varnish that dries by solvent evaporation.

Laminate Flooring
A type of flooring made of compositions of MDF board and multiple layers of impregnated papers and aluminum oxide. Sold as planks and panels in wood, stone, tile and other looks.

Large Format Tiles (LFT)
Is 15″ (38 cm) or greater on any side as well as heavier natural stone such as marble, granite, travertine, slate and limestone. These mortars may be applied up to 3/4″ thick and provide superior coverage and bond strength while reducing lippage between tiles.

One of the first resilient floors, it was introduced in the 1800s. 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.

Luxury Vinyl Tile (LVT)
The durable construction of luxury vinyl tile (LVT) includes a protective wear layer which resists scuffs, tears, gouges, rips and scratches. Additionally, LVT is affordable, durable, resilient, resistant to water, and can be installed virtually anywhere in your home. Suitable for both residential and commercial applications.


Limestone flooring known for its elegant appearance created by polishing its very hard surface. Now available in tiles.

Moisture Resistance
Three types of moisture conditions may exist: 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 excessive.

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



Natural Fibers
The term natural fiber refers to any type of fiber that is not man-made (i.e., synthetic). Many different natural fibers are used in carpet, with the most popular being wool. Other natural carpet fibers include seagrass, sisal, and jute.

Natural Stone
The term “natural stone” refers to a variety of mountain-born mineral substances that stand in contrast to any synthetic or manufactured stone products. Common natural stone flooring includes slate, marble, limestone, travertine, granite, and sandstone —each of which has slightly different properties.

Nylon Carpet
In overall performance characteristics, nylon is the most versatile of all fibers, providing excellent durability and flexibility in creating a variety of carpet styles. Nylon is the most commonly used carpet fiber and can be found in a wide range of both cut pole and loop pile styles.


Outdoor Carpet
Carpet designed to be used outdoors on patios, walks and decks. Usually made of polypropylene to withstand the weather and ultra-violet rays of the sun, most outdoor carpet is designed for glue-down installation.

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. Most common finish for wood flooring.

Oil-Treated Finish
An oil based finish for hardwood flooring.

Olefin Carpet Fibers (see Polypropylene)
Olefin is the generic name for polypropylene, a synthetic fiber used to make many different products, including carpet. In the carpet industry, the terms olefin and polypropylene are typically used interchangeably, as they both mean the same thing.

Overlap Reducer
Used to transition between hardwood and carpet. Sits on top of finished material creating an overlap to cover the expansion gap.

Overlap Stair Nose
Function as the finishing transition for the edge of a stair on a floating floor system. Sits on top of finished material creating an overlap on the top of the stair thread.


A building material manufactured from with wood fragments, such as chips or shavings, mechanically pressed into a sheet and bonded together with resin.

Plush Carpet
A smooth, dense cut pile carpet in which individual tufts are only minimally visible, and the overall visual effect is a single level of giver ends.

Patterned or Printed Carpet
Carpet having patterns applied by methods similar to printing paper. These include flatbed screen printing, rotary screen printing, stalwart printing and modern computer programmed jet printing.

The upright ends of yarn, whether cut or looped, that form the wearing surface of carpets or rugs. Sometimes called the face or nap of the carpet.

Making a series of parallel cuts into a log. This is known as the easiest way to make wood planks. Also referred to as flat-sawn.

Polyester Carpeting
Polyester by nature has a high luster appearance, which translates into carpets of beautiful colors. Compare a polyester carpet with a nylon carpet of the same color, and you’ll notice the difference. Polyester appears much more vibrant, while the nylon has a more dull or matte finish.

Polypropylene Carpet Fibers (see Olefin)
Olefin is the generic name for polypropylene, a synthetic fiber used to make many different products, including carpet. In the carpet industry, the terms olefin and polypropylene are typically used interchangeably, as they both mean the same thing.

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.

Porcelain Tile
Porcelain tile is a type of dense, durable ceramic tile that does not easily absorb water or other liquids. Both tiles are manufactured similarly using baked clays, so it is primarily the strength and density the tiles that separates the two.

Flooring that is stained and sealed before installation, usually done at the flooring factory.

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.


Quarry Tile
Glazed or unglazed ceramic tile made using an extrusion process. An example is the terra-cotta squares used in the Southwest.

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

The log used to create wood floor planks is first cut into quarters and then cut into boards using parallel cuts.

A hard white or colorless mineral consisting of silicon dioxide, found widely in igneous, metamorphic, and sedimentary rocks. It is often colored by impurities (as in amethyst, citrine, and cairngorm). Quartz countertops are man-made even through quartz is a natural material. Quartzite countertops are natural.

R - S


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.

Rebond Padding
Eco-friendly, comfortable rebond carpet padding is made from recycled scraps of high-density foam bonded together. It’s ideal for use with trade show carpet, and also an economical option for applications requiring carpet padding for one-time use.

Reducer Molding
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.

Refers to the practice of sanding down a wood floor and finishing it again, to reduce the appearance of damage, wear, and tear. A solid wood floor can be sanded and refinished many times. However, an engineered wood floor can only be sanded and refinished if the veneer is 2mm or thicker.

A remnant is a smaller piece of carpet that is typically the ‘end of the roll’ usually left over from a previous job. Remnants vary in size, usually ranging from about 3 feet up to around 25 feet, but they can be any size. They are often sold ‘as is’, meaning that they do not come with a full warranty, but they are generally offered at discounted prices.

Resilient Floor
Smooth-surfaced flooring (tiles, strips, or sheet goods) are manufactured by first combining a plastic material with filler and pigments, and then processing them into sheets of different thickness. If a backing material is used, the plastic sheet is joined to the backing. Types include solid vinyl, backed or cushioned vinyl, rubber, cork, and linoleum.

A method of cutting a log into boards that ensures each board has the same relation to the log, providing the same grain pattern. This is the most stable lumber. 

Rotary-Peel Cut
Refers to a cutting method used to create a solid hardwood veneer for the top layer of an engineered hardwood floor. It involves boiling the log for a certain amount of time at a certain temperature to prepare the wood. After the wood has been prepared, it is scraped from the log with a blade working from the outside in and then pressed flat. It typically has a plywood-like grain and can have issues with cupping and warping to try to revert to its original shape.


Sculptured Carpet
Any carpet pattern formed from high and low pole areas, such as high-low loop or cut-and–loop.

A grasslike plant that lives in or close to the sea, especially eelgrass. Seagrass carpet is one of a group of natural floor coverings that are environmentally friendly and are becoming increasingly popular as we become more aware of eco-friendly practices and materials.

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

The line along which two pieces of sheet flooring are joined.

Shag Carpet
A deep-pile texture with long-cut surface yarns. Shag carpet was popular in the 1970s and a new type of contemporary shag in more up to date colors is gaining in popularity today.

The Sisal plant is a Mexican agave with large fleshy leaves, cultivated for fiber production. Sisal carpet is a natural carpet fiber extracted from Agave plant’s long spiny leaves (species Agave sisalana). Sisalana is a highly durable carpet often used in heavy traffic areas and higher end homes. It can be used as a wall-to-wall carpet, an area rug, or runner.

Solid Surface Countertops
Solid surface is a non-porous low-maintenance material used for surfaces such as countertops. It can mimic the appearance of granite, marble, stone, and other naturally occurring materials. A major appeal of solid surface is its impermeability.

Spread Rate
The amount of coverage which can be expected from a given amount of adhesive when spread using the recommended trowel.

Stair Nosing
A molding designed for the purpose of trimming a stair landing or the border of an open room that adjoins a room that is a lower level. One side possesses a rounded nose. Available prefinished with urethane to blend with the floor or available unfinished.

Stair Risers
The vertical board under the tread in a set of stairs.

Stair Treads
The horizontal board which forms the “walking” portion of the set of stairs.

Strand Woven Bamboo
Bamboo is a rapid growing grass that reaches maturity very quickly, meaning that it can be harvested every five years. To make natural strand woven bamboo flooring the bamboo is cut, stripped down, shredded into fibers and woven together. It is then compressed under extreme heat and pressure along with a resin.

A floor laid as a base for underlayment, resilient floor covering or other finished flooring. Most commonly plywood or concrete.

A smooth surface used beneath floor covering – such as concrete, underlayment, or existing resilient flooring.

The term synthetic refers to man-made, synthetic carpet fibers are man-made carpet fibers, and include nylon, polyester, olefin, and Triexta.



A molding designed for obtaining an expansion space up to 1/2″ wide between two different Armstrong hardwood floors or hard surface floors of the same thickness or as an internal expansion space for long spans. It is 3/8″ thick x 2″ wide x 78″ long and prefinished in urethane to blend with the floor or available unfinished.

A smooth, multicolored floor made of marble or stone chips embedded in a cement binder, and the highly polished. Traditionally terrazzo floors are poured and set on site but manufactured terrazzo tiles are also available.

A molding designed for the purpose of completing an installation around or next to sliding glass door tracks, fireplaces, carpeting, ceramic tile, and other objects so as to maintain a proper expansion space next to Armstrong hardwood floors and to obtain a good transition. Threshold is 2″ wide x 78″ long and prefinished in urethane to blend with the floor or available unfinished.

Tongue and Groove
In strip, plank and parquet flooring, a tongue is milled on one edge and a groove cut on the opposite edge. As the flooring is installed, the tongue of each strip or unit is engaged with the groove of the adjacent strip or unit. 

In carpeting terms, twist can refer to either a style of carpet that is highly twisted (a frieze, as described above) or to the twist number of a carpet. The twist number is the number of times carpet strands have been twisted in a one-inch length of fiber. The twist number is one of the most important components of a carpet’s durability.


The layer of material that is laid loosely between the sub-floor and and the main flooring. It serves one or more of the following functions: vapor barrier, padding, sound barrier and/or insulation. Examples of underlayment include foam, rosin paper/felt, cork, plastic sheathing or Quiet Walk.

UV Cured Polyurethane
A special type of polyurethane that is cured by subjecting it to a specific dosage of radiation in the form of ultraviolet light. See Polyurethane and Ultraviolet.


Vapor Barrier
A material, such as foil, plastic film or specially coated paper, with a high resistance to vapor movement, used to control condensation or prevent migration of moisture. b.) Any material used to stop the migration of vapor through walls, floors or ceilings.

A finish that contains either natural or synthetic oils that are refined by boiling and cooking with the addition of dryers. Slow to cure, but can be accelerated by the addition of heat. When used as a sealer, it is often burnished with a buffer and pads, the friction of which accelerates the curing process. Ambers well, somewhat stain and spot resistant, but may be scratched easily when new due to slow curing time.

A thin layer of real, solid hardwood glued to the top of a core board to create an engineered wood floor. Veneers can vary in thickness from 0.6mm to 6mm. Veneer thickness dictates how many times an engineered wood floor can be sanded and refinished. If the veneer thickness is less then 2mm then the floor cannot be sanded or refinished at all.

Synthetic resin or plastic consisting of polyvinyl chloride or a related polymer, used especially for floor covering needs. Sheet vinyl flooring is vinyl flooring that comes in large, continuous, flexible sheets. A vinyl sheet floor is completely impermeable to water, unlike vinyl floor tile, which comes in stiff tiles, and vinyl planks, which come in interlocking strips.

Vinyl Composition Tile
A resilient tile floor covering composed of binder, fillers and pigments compounded with suitable stabilizers and processing aides. The binder consists of polymers and/or copolymers of vinyl chloride, other modifying resins, and plasticizers. The tile meets requirements of ASTM F 1066, Standard Specification for Vinyl Composition Floor Tile.


A general term describing any distortion in a piece of wood from a true plane.

Water-Base Urethane
A waterborne urethane that is fully cured and dries by water evaporation. See Polyurethane.

Wear Layer
The portion of a resilient floor covering that contains or protects the pattern and design exclusive of temporary finishes or maintenance coatings.

Wool Carpet
The dense, soft, often curly hair forming the coat of sheep and certain other mammals, such as the goat and alpaca, consisting of cylindrical strands of keratin covered by minute overlapping scales and much valued as a textile fiber.

Form (fabric or a fabric item, ie carpet) by interlacing long threads passing in one direction with others at a right angle to them.

Not seeing the answer to your question? Contact our knowledgeable team today, or stop by our showroom! We’re here to help with your remodeling project needs, from the floor up.