Sun Shade Screens Glossary of Common Fabric Industry Term Definitions | MermetUSA
  • Search
  • 0
      There are no items in your cart

Sun Shade Screens Glossary of Common Fabric Industry Term Definitions

Building Envelope

The physical separator between the conditioned and unconditioned environment of a building including the resistance to air, water, heat, light, and noise transfer.


The illumination of buildings by natural light.


The measurement of the thermal properties of the materials used in the arrangement of windows and doors on a building. 


Glare is the presence of harsh bright light such as direct or reflected sunlight or artificial light that can make it difficult to see.


Glazing, which derives from the Middle English for 'glass', is a part of a wall or window, made of glass.

Infrared Light (IR)

A wavelength just greater than that of the red end of the visible light spectrum but less than that of microwaves. Infrared radiation has a wavelength from about 800 nm to 1 mm, and is emitted particularly by heated objects.


Knit fabrics consist of rows of loops intertwined around each other. The way the loops are intertwined gives unique patterns to different styles of knit fabrics.

Noise Reduction Coefficient (NRC)

NRC stands for Noise Reduction Coefficient and is the average of a product's ability to absorb sound waves at 4 frequencies (250, 500, 1000 and 2000 Hz), which are the range of frequencies of human speech.

Openness Factor (OF)

Openness factor represents the woven density of a fabric, the percentage is the amount of physical holes in the fabric. 


A single yarn of the weft, crossing the warp, is called a pick.


A liquid substance that can be converted into a solid plastic simply by heating, consisting of particles of synthetic resin dispersed in a nonvolatile liquid.


This stands for Polyvinyl chloride, the third-most widely produced synthetic plastic polymer.


“Railroading Fabric” is an option that helps you avoid “seam lines” on large windows that exceed the width of the fabric roll. The fabric is turned 90 degrees clockwise from its normal direction.


Abbreviation for the thermal properties of the total sun's energy. 100% of the sun's energy must be either Reflected, Absorbed, and Transmitted. Rs + As + Ts = 100%.

Solar Energy

The total amount of energy the Earth receives from the sun. This is further broken down into different spectrums of energy, Ultraviolet light, Visible light, and Infrared radiation.

Solar Heat Gain Coefficient (SHGC)

The percentage of solar energy able to pass through the glazing system and fabric as heat. Lower SHGC values equate to better heat blocking by the glazing system and fabric.

Sound Absorption Average (SAA)

SAA stands for Sound Absorption Average and is the average absorption of sound waves from 12 octave frequencies ranging from 200 - 2500 Hz. It supersedes the NRC because it has a wider range and more points of measure.


A heat treatment process that sets the warp and weft yarns of the woven fabric at right angles to each other. This process locks the yarns together to give the fabric dimensional stability and strength. 

Total Solar Absorption (As)

Total amount of solar energy that is absorbed into the material. Any energy absorbed by a material is converted to heat and eventually released in the surroundings.

Total Solar Reflectance (Rs)

Total amount of solar energy reflected by the material. The higher the reflection value of a material, the better heat blocking capability it will have.

Total Solar Transmission (Ts)

Total amount of solar energy that able to pass directly through the material. This includes UV, Infrared and Visible Light.

UV - Ultraviolet Light

An invisible part of the electromagnetic spectrum of the sun's energy. These shorter wavelengths come before the visible spectrum and are known to cause color fading damage to materials.

Visible Light

The part of the electromagnetic spectrum of the sun's energy in which we can see. These wavelengths reflect off objects back to our eyes and make up all of the colors of the rainbow. 

Visible Light Transmission (VLT)

Percentage of visible light that is transmitted through the entire window system. Openness factor and color affect the VLT of materials. The VLT value is associated with glare control and view through capability. The greater the VLT reduction percentage, the less light passes through.


Warp is the lengthwise, longitudinal, or machine direction of a roll or a term used for individual lengthwise yarns.


Weft is the term used to describe the yarns drawn perpendicularly through the warp yarns to create cloth.


Woven fabrics are created by interlacing yarns at roughly right angles to one another. The long constant threads which run vertically in the fabric are the warp and yarns that run perpendicular to the warp are the weft.

Want to order free samples of our fabrics?
Browse swatches and order samples online >