Glossary of Terms:
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.
Glare
Glare is difficulty seeing in the presence of bright light such as direct or reflected sunlight or artificial light such as car headlamps at night.
Glazing
Glazing, which derives from the Middle English for 'glass', is a part of a wall or window, made of glass.
Infrared Light (NIR)
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
Knit fabrics consist of rows of loops intertwined around each other (see Figure 1.2). The way the loops are intertwined gives unique patterns to different styles of knit fabrics. Warp knit fabrics wrap these loops around straight warp yarns, which give the fabric structure.
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
Openness factor tells you how much light your shades will let through in a percentage that is formed by the ratio of openings in the fabric.
Plastisol
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.
Railroading
“Railroad 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.
Solar Energy
The energy the Earth receives from the sun, primarily as visible light and other forms of electromagnetic 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.
Tentering
Tentering sets the warp and weft of woven fabrics at right angles to each other, and stretches and sets the fabric to its final dimensions. The fabric is stretched by the use of a tenter frame, consisting of chains fitted with pins or clips to hold the selvedges of the fabric, and travelling on tracks.
Total Solar Absorption (As)
Total amount of solar energy that is absorbed. 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
A form of radiation which is not visible to the human eye. It's in an invisible part of the "electromagnetic spectrum". Radiated energy, or radiation, is given off by many objects: a light bulb, a crackling fire, and stars are some examples of objects which emit radiation.
Visible Light
A form of electromagnetic (EM) radiation, as are radio waves, infrared radiation, ultraviolet radiation, X-rays and microwaves. Generally, visible light is defined as the wavelengths that are visible to most human eyes.
Visible Light Transmission
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.
Weft
In weaving, the weft (sometimes woof) is the term for the thread or yarn which is drawn through the warp yarns to create cloth.
