Mattress Terms

Air Beds

Sleep system that features air chambers that can be filled or expelled to adjust the support of the mattress. Typically upholstered with cushioning materials and a quilted mattress cover.


Air Mattress

A vinyl or rubber mattress core that is filled with air, and typically is not upholstered.


Bed Frame or Bed Base/Frame

Refers to the frame or type of platform the bed will be resting on. Usually, a metal or wooden frame with legs is used to raise, suspend or support a bed above the floor, headboards can be attached to the frame. All queen and king size sets require a frame that is either metal with a center support bar and vertical center leg, or on a headboard/footboard system with a minimum of five slats (1″ x 4″) with a vertical center support.


Bed Rails

Metal or wood frames that connect the headboard and footboard together and also support the mattress set. Most commonly in a hook-on or bolt-on style.


Body Impressions

The normal compression of upholstery layers as they lose resilience over time. Often mistaken for sagging. Usually appearing in the center of the bed, body impressions can be minimized by rotating or flipping the mattress. While considered normal, these should not exceed 1-1/2″.


Bonnell Coil

An hourglass-shaped mattress coil usually with five turns; cylindrical at the top and bottom and tapered in the center.


Border Rod

A heavy wire placed around the perimeter (top and bottom) of a non-foam encased mattress and/or box spring. The border wire is attached to the outermost coils, providing shape and form for the mattress and/or foundation.


Box Spring

Traditional style mattress foundation constructed with coils mounted on a wooded frame. The box spring coils are attached at the top with a wire grid top and upholstered.



Usually a twin-size mattress used on bunk beds. Sometimes a mattress and wooden frame are combined so a bunkie board is not necessary.


Bunkie Board

A platform base or a board usually covered with material or fabric. Typically used under mattresses on bunk beds.


California King

A bed that measures 72″ x 84″ as opposed to the more common 76″ x 80″ king size bed. Widths and lengths can vary +/- 1/2″ due to upholstery thickness. Sometimes referred to as a Cal-King or Western King.



Non-woven cloth that covers the bottom of the box spring unit. Also called a “dust cover.”


Center Rail

A support beam running head-to-foot or side-to-side down the middle of a foundation or frame for added support.


Channel Quilt

Stitching in lines parallel to the length or width of the fabric.


Clipped Border Rod

A border rod attached to coils by a steel clip as opposed to a small spun wire known as a helical wire.


Coil Count

The specific number of coils in a mattress or box spring. The standard count is based on the coils within queen-size units. A high coil count does not necessarily indicate better quality. Rather, the design of a coil, the gauge of wire used and the way the coil is engineered determines the comfort, support and durability that it will provide.



The individual wire springs that are the major components of an innerspring unit.


Comfort Layers

The upholstery material in a mattress between the innerspring unit and the mattress cover that provides the comfort of the mattress.


Cone-Shaped Coil

Used in coil box springs. These coils are wide at the top and pointed at the base. The special cone-shaped design allows even compression over the entire coil.


Continuous Coil

A mattress configuration in which each row of coils is made using a single, continuous wire.


Continuous Quilt

Multi-needle quilting featuring a continuous pattern. The tighter (closer together) the pattern is, the firmer feel the top will have.



The finished covering of a mattress; also known as ticking.



Materials that are between the innerspring unit and the ticking in an innerspring mattress.


Damask Cover

Usually a tone on tone colored heavy fabric woven on a loom. Usually featuring designs and patterns woven into the fabric against a flat background used to cover mattresses.



A measure of weight per cubic volume. Usually expressed in pounds per cubic foot. An important quality of foam, independent of firmness. Greater density in foam means more durability. Density can also mean number of coils per given area or wire surface coverage.



The top upholstered comfort section, typically of a softer more conforming mattress, indicated by an additional side gusset border and taped edge.



A loss of load-bearing capacity in a mattress.



A product for cushioning, produced from cotton fibers combined and laced together by a “garnet” machine.



A natural or synthetic substance, which may be separated into thread-like filaments that can be spun, woven or matted. Heavier polyester fibers are bonded and compressed into pads used as insulators and to add firmness to the comfort of a mattress. Softer synthetic or natural fibers, like batting are used to create surface plushness in the quilt.



The cushioning material in quilting between the fabric and the quilt backing.



A sought after quality, usually interpreted to mean support. For some, firmness is a comfort term synonymous with hardness; for others, it is a structural term associated with the support of the innerspring unit.



The process of sewing a fabric to the cover edge and attaching it to the innerspring unit. It secures the cover and reduces the possibility of shifting.



Refers to the turning over of the mattress so that the top becomes the bottom. Double-sided mattresses should be rotated and flipped at the same time. Single-sided mattress should be rotated for optimum service.



Upholstery or cushioning materials used in mattresses. Different types include latex, polyurethane and Viscoelastic (memory foam or gel foam).



The bottom part of the mattress set that gives mattress support and durability.



The measure of the diameter of wire used in a mattress and/or foundation. The lower the gauge, the heavier/thicker the wire.


Gel Memory Foam

The newest generation of memory foam that utilizes gel to further reduce heat from being trapped, and toincrease support characteristics.



The steel wire assembly that forms the top surface of a foundation. Usually welded into a lattice to which steel supports are affixed.


Helical Wire

Thin wire spirals that hold adjacent rows of coils together and may be used to hold coils to the border rods. They may run horizontally or vertically. Not present in mattresses with individually pocketed coils.


Hinged King

A king size sleep set that features a mattress with divided border rod in the center to allow for slight bending or folding without damage.


Hog Ring

A staple used to secure the flange and insulators to the innerspring unit.



Initial Load Deflection. A measure for the firmness level of foam.


Inner Panel

A true pillow top mattress will have an “inner panel,” meaning the first several layers of upholstery are actually covered with a layer of fabric that is sewn to the tape edge. The pillow top would be a separate section of layers positioned on top of the inner panel.


Inner Tufting

A method of attaching and combining layers of padding below the quilted cover of a mattress.


Innerspring Unit

The spring and wire unit made up primarily of coils and helicals, which is the inside of an innerspring mattress.



Separates mattress coils from cushioning. Usually a compressed polyester fiber pad, compressed cotton, or a polypropylene mesh screen used to separate and protect foam upholstery layers from the innerspring unit.


Kiln Dried Wood

Wood hat has been heated in a kiln to help prevent warping or splitting. The wood used in mattress foundations is typically kiln dried.


Knit Fabric

A fabric used for mattress covers that is made from polyester or nylon. It is knitted as opposed to woven and is softer and more “stretchy” than other fabrics.


Lacing Wire

Helicals formed from finer gauges of wire that attach rows of coil springs together.



Foam rubber made from the rubber tree or synthetic rubber. This product is typically used in premium mattresses and is naturally hypoallergenic.



A term used broadly for products used for sleeping. Derived from the Arabic word “matrah,” meaning to throw down.


Mattress Handles

Cords or fabric that are usually sewn into the padding to aid in positioning the mattress on the foundation.


Memory Foam

Memory foam is polyurethane with additional chemicals increasing its viscosity and density that softens in reaction to body heat. It is often referred to as “visco-elastic” polyurethane foam.


Micro Coils

One-inch to 3-inch tall individual coil springs, pre-tensioned and wrapped in a non-woven fabric. Rows of pocketed coils are typically glued together to make a pocketed mini coil mattress topper.



Refers to the movement of the fiber quilt in the quilt of a mattress. Some fiber layers start moving away from the areas of usage. Good quality fibers and certain quilt patterns can reduce this effect.


Offset Coil

A metal hourglass-shaped coil evolved from the Bonnell coil. The top and bottom turns are flattened on opposite sides for a better “hinging” action when laced together with helical wires.


Platform Foundation

A wooden foundation with no metal wire. Usually covered with a layer of foam and fabric to look like a box spring.



The top upholstered comfort section, typically of softer, more conforming mattress, indicated by an additional side “V” shaped gusset and taped edge.


Pocketed Coils

Individual coil springs, pre-tensioned and wrapped in a non-woven fabric. Rows of pocketed coils are typically glued together to make a pocketed coil innerspring unit.



A sign of mattress wear where upholstery layers separate down through the surface of the innerspring coils.



A word created by the bedding industry to describe additional support in the center of a mattress or foundation unit.


Pressure Points

Specific areas of the body where blood flow through the capillaries is restricted due to pressure against that area, causing discomfort and tossing and turning.



The top few layers of upholstery that are stitched together with a backing material. Simple quilting may consist of backing material, 1/4″ of foam, and the fabric cover. Upper-end quality mattress may have multiple layers of foam and various fibers, synthetic and/or natural.



Ability to spring back. A term used to describe the property of foam, fiber, fabric or spring unit to spring back to its original form.



The result of a worn out or defective mattress that sags in the center, causing your body to want to roll towards the center.



Turning your mattress so that the head of the bed becomes the foot, allowing the bed to wear evenly.



Structural effects of wear causing loss of support and indentation of the surface of an innerspring mattress. Often confused with normal settling of upholstery layers defined as body impressions.



A wooden board used as the bottom structure to support box spring units within their frames. Also used in complete beds with wood rails and in bunk beds to support the mattress in place of a box spring.


Smooth Top

Industry term used to describe a mattress cover that isn’t quilted.


Split Queen Box

Two queen size foundations, each measuring 30″ by 80″, designed to accommodate the passage of a single-piece foundation.


Spring Wire

Tough, durable wire made from high carbon steel used to make innerspring mattress coils.



The ability to bear weight.


Tack and Jump

A quilting process in which stitching is in specific spots, and not connected as in multi-needle quilting. The result is a more tufted look that allows for the upholstery layer to rise to a more fuller loft.


Tape Edge

The cord-like seam that is stitched to connect border panels to the top quilt panels of a mattress.


Tempering/Stress Relief

Process using either heat or electric charge to realign the molecules in wire after it is formed into coils to create more strength, resiliency and durability. Tempering helps assure that the wires will return to their original shape after compression.



Term used for mattress and foundation fabrics.


Topper Pad

Insulation and padding material on top of the spring assembly.



A process in which twine, cord or threads are drawn tightly through a mattress to hold padding into place.


Upholstery Layers

All the layers of material (comfort layers) of a mattress, including the insulators and quilted covers.


Visco-elastic Foam

Visco-elastic foam is polyurethane with chemicals added to increase its viscosity and density. Visco-elastic foam softens in reaction to body heat. It is often referred to as “memory” foam.