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Carpet Terms Glossary

If you’re not familiar with the carpet industry, you may be wondering just how many words there can be that are associated with such a simple product. But carpet can actually be a lot more complex than many people suspect, and it comes with an entire lexicon of carpet-related terminology. This glossary of carpet terms and their definitions from the friendly team of Minneapolis carpet service professionals at 651 Carpets will come in handy next time you need to know what BCF means, or are wondering about the difference between cut-pile and loop-pile.


Abrasive Wear: A type of damage that causes carpet to change texture (and sometimes color) due to friction from foot traffic.

Any Width: When a manufacturer offers the same style and color of carpet in every standard width to make it easier for installers to avoid wasting carpet during an installation.

Attached Cushion: Carpet with underlayment pre-attached or bonded with the backing to form a single unit that is ready for installation.

Average Pile Density: A measure of how densely packed the pile yarns are in a cubic yard of carpeting, expressed in ounces per yard. The formula is Density = Pile Yarn Weight x 36 / Pile Thickness or Pile Height.


Backing: The fabric, polymer compounds and other material that pile is tufted into or glued onto to form a piece of tufted, flocked or bonded carpet. Tufted carpets have both primary backing and secondary backing.

BCF (Bulked Continuous Filament): Continuous strands of synthetic yarn that are fabricated through an extrusion process without the need for spinning. BCF polypropylene and nylon yarns are used for synthetic carpet manufacturing.

Berber: A generic term for any cut-pile or loop-pile carpet manufactured with naturally-colored yarns. Originally, use of the term Berber carpet was limited to carpets hand-made by the Berber people, but the meaning expanded into a more general term over time.

Bonded: A type of carpet that is manufactured by gluing pile yarn onto a backing with an adhesive coating rather than tufting them with a needle.


Carpet Repair: The process of fixing appearance and structural problems with damaged carpet by gluing in new fibers, stretching, patching, cleaning and using other carpet repair techniques.

Compression: When carpet pile yarns are flattened by continuous pressure from a heavy object such as a piece of furniture.

Crimp: A fiber treatment that leaves yarns with a wavy texture to improve the handle and bulk of a finished piece of carpet.

Crocking: A sign of deterioration in which fibers fade in color because they have lost dye through wet or dry friction from foot traffic or rubbing. Crocking happens because of poor dye penetration, faulty dyeing methods, inadequate post-dye treatment or insufficient dye fixation.

Cut-Pile: A style of tufted carpet where the pile yarns are cut so the end of the yarn tufts forms the visible carpet surface.


Delamination: A kind of damage where the primary backing on a tufted carpet separates from the secondary backing.

Denier: A measurement unit that represents the fineness of yarns, equal to the weight in grams per 9,000 meters of yarn.

Design Repeat: A measurement unit that represents the length of a stretch of carpet before its design is repeated.

Differential Dye: A dyeing process in which yarns are pre-treated with compounds that either improve or resist dye absorption, causing color variations along the length of the yarn so the finished fabric or carpet has a mottled or flecked appearance.  

Dye Fastness: The ability of carpet yarns to retain their color when exposed to fading agents such as ultraviolet light, carpet shampoo and friction.


Extrusion: A method of fabricating synthetic fibers by forcing fiber-forming materials such as polymers through a hole in a spinneret to create a single filament strand of yarn.


Face-to-Face: A carpet manufacturing process that involves attaching yarn tufts to two backings on either ends of the tuft and then cutting down the middle to create two cut-pile carpets.  

Fixed Width: Carpet that is only available in the manufacturer’s standard width, typically 12 or 15 feet.

Flocked Carpet: A type of carpet that is manufactured by applying short lengths of fiber, called flock, to a backing coated in adhesive, usually with an electrostatic process. 

Foam Back: A type of attached cushion carpet with a secondary backing made of foam material.

Foot Traffic Unit: A measurement unit of foot traffic; one unit represents the effects of a pedestrian walking across a section of carpet once. Light foot traffic is considered fewer than 100 units in a day, between 100 and 1,000 daily is moderate, heavy traffic is between 1,000 and 10,000 foot traffic units in a single day, and more than that is considered extra heavy foot traffic. Residential foot traffic is usually light to moderate, while foot traffic in commercial settings or public spaces is typically heavy or extra heavy.

Frieze: A type of carpet with a bumpy, rough appearance and texture that comes from extra-twisted pile yarns.


Gauge: A measure of the number of pile yarns per inch, expressed as a fraction of an inch. A 1/8 gauge, for example, means there are eight yarns per inch.

Grade: An assessment of the quality and durability of carpet material that is assigned by the manufacturer. There is no universal grading system for carpet, so the meaning of different grades or grading scales can vary according to the manufacturer.

Grinning: When the primary backing of a carpet is visible between the rows of pile yarns. This problem indicates a faulty manufacturing process or a very low-density pile.


Handle: The textural or tactile qualities of a carpet, such as pliability, smoothness and softness. 

Hessian: A secondary backing for tufted carpets made of woven jute material.

Hybrid Carpet: A type of carpet made of a combination of two or more types of yarns, such as a wool and synthetic blend.


Jacquard: 1. A mechanical fabric patterning device that controls the patterning components of a loom with a punched card mechanism. 2. Fabric produced on a jacquard loom.


Latex: 1. A milky fluid found in plants such as rubber trees that is mixed with chemical additives and applied to a carpet’s secondary backing to make it water resistant. 2. Synthetic materials that resemble latex, formed by a dispersion of water in polymer particles.

Loop-Pile: A type of tufted carpet in which both ends of a yarn strand are tufted into the carpet backing and the carpet surface is formed by the looped end of the strand.

Luster: A quality of brightness or the ability to reflect light in fibers such as carpet yarn. Synthetic pile yarns are classified into categories like semi-dull, semi-bright and bright by manufacturers.  


Matting: When fibers tangle together into solid clumps, or mats. Matting occurs due to a combination of abrasive wear from foot traffic and ground-in dirt working its way into the fibers over an extended period of time. Matting is usually not reversible and the best solution is a new carpet installation.

Metameric Color Match: Two differing materials that appear to be an exact color match under some lighting conditions, but look different in other lighting conditions. This can occur when the materials are colored with different pigment types.


Naturals: 1. Carpet material fabricated from natural fibers such as jute, seagrass or sisal. 2. Synthetic composite fibers that mimic the appearance and texture of 100% natural fibers.

Non-Woven: Carpet fabric in which the fibers or yarns are attached to the backing with adhesives or chemical bonding agents rather than being woven or tufted. 


Over-Tufting: A manufacturing process in which a plain but complete tufted carpet is put through a tufting machine again to have a design applied in a longer length of pile yarn.


Pile: 1. The visible surface of a carpet installation, composed of loop-pile or cut-pile yarn tufts. 2. The density of carpet yarns, as determined by the weight and thickness of the yarn pile.

Pile Thickness: The length of the pile yarns from surface to backing, not including the backing.

Pile Weight: The total weight of the pile yarn in a carpet, expressed in grams per square meter or ounces per square yard.

Pilling: A sign of abrasive wear in which little balls of fiber are attached to the surface of the pile. Certain materials such as wool and some types of synthetics are more prone to pilling.

Ply: The number of yarn strands that are twisted together to form a single strand; two-ply carpet, for example, is fabricated with yarn strands composed of two single strands.


Rippling: Waves or wrinkles in a carpet installation, typically caused by heat and humidity warping the backing. The best carpet repair solution for this problem is stretching the ripples out and refastening the carpet at the edges of the room so it lies flat. 


Saxony: A type of tufted carpet with a level cut-pile and clearly defined tufts that are longer than velvet and have a lower average pile density. 

Scotchgard: A brand of fluorochemical compound that is applied to pile yarns during the manufacturing process to give them greater resistance to dirt and staining.

Seaming: The process of joining two sections or lengths of carpet together during installation. Seaming is more difficult with patterned carpet because the pattern needs to line up perfectly to make the seam invisible.

Shading: A visual phenomenon that occurs when cut-pile carpet lies in differing directions, causing it to appear lighter and darker in areas because of the way it reflects light. Some people take advantage of the shading effect to make uniform lines on the carpet with a vacuum. 

Shag: A style of carpet with an extra-long pile length that exceeds three-quarters of an inch and can be several inches long.  Shag carpeting was very popular in the 1960s and 1970s, but it is now usually seen as outdated and is not typically produced by modern carpet manufacturers.

Streaking: When a carpet has a lined or streaky appearance caused by issues such as yarn variation, faulty dyeing methods or poor tufting.


Tip Shearing: 1. The process of trimming pile yarns with scissors to even out the surface. 2. A pattern created by shearing off the tips of some loops in a multi-height loop-pile tufted carpet.

Tufted: A type of carpet that is constructed by using a needle to insert individual yarn tufts into a pre-made backing. The yarn pile tufts can be looped with both ends inserted into the backing, or cut to form a fluffy cut-pile surface.

Twist: A measure of how many twists or spirals are in the bundles of fibers that form yarn strands in carpet pile, usually expressed in turns per inch (tpi).


Underlayment: A thin layer of padding like felt, rubber or foam that is installed under carpeting to give the floor a cushioned feeling underfoot and provide support for the carpet so it doesn’t take as much abrasive wear damage over time. Underlayment is sometimes referred to as underlay or cushioning.


Velvet: A type of carpet with a very dense, low pile made from fine, twisted yarns.

Vinyl (PVC, Polyvinyl Chloride): A synthetic polymer that is used as a non-slip backing on carpeting.


Warp: Lengthwise yarns that are held stationary on a loom during fabrication while the weft yarns are woven in and out of the warp yarns. For the purposes of carpet fabrication, the warp yarns are typically reinforced with wire.

Weft: Transverse yarns that are woven through the stationary warp yarns on a loom during the fabrication process.

Wool: Natural fibers spun from sheep fleece, often used in natural carpets or blended with synthetic fibers for wool-blend pile yarn.


Zippering: A type of damage that appears on tufted loop-pile carpets in which long tufts are pulled out of the backing. This happens because the tufts are not securely fastened into the backing with an adhesive compound.