top of page
  • Writer's pictureBennett Glass Company

Fenestration Common Terms:

Little lost in all the nomenclature? Here are some common terms your will frequently find in fenestration installations.


Authentic/ True Divided Lites - Individual panes of glass stopped into a window or door with divisions between the glass

Awning Window - Type of window that hinges from the top and opens outward from the bottom.

Bi-Folding Door - A type of (typically) exterior doors that folds 2 panels or more that fold to either side.

Call Out Sizes - Varying by manufacture, call out sizes are rough estimates for window and door sizes, usually listed on architectural drawings and/or plans.

Casement Window - A type of window that cranks or pushes open either from the left or right.

Caming - A aesthetic detail usually incorporated into entry doors, sidelites and transoms that uses a metal divider with decorative glass patterns.

Corner Window - Usually incorporated into more contemporary designs, this is window that wraps around the corner of a building.

Door Jamb - The frame that the door panel is hinged to.

Double Hung Window - Consists of two moving sashes, one that moves top to bottom and other other bottom to top.

Egress - Applicable to all bedrooms that do not have a door leading to the outside, Egress specifications are calculated so that fireman with an air pack can easily get someone out of the home in a fire situation.

Emissivity - The measure of an object's ability to emit infrared energy. Emitted energy indicates the temperature of the object. Emissivity can have a value from 0 (shiny mirror) to 1.0 (blackbody).

Fenestration - The arrangement of windows and doors on the elevations of a building.

French Casement - A pair of casement windows mulled together, one left and one right, that when in operation have no spacer or divider bar between the 2 windows, giving the look of a French door.

French Doors - With a thicker bottom stile (typically 12 inches but varies by manufacture), this is a very popular style for most colonial, craftsmen homes and can come in either sliding, in-swing or out-swing configurations.

Garden Window – A type of window whose ledge sits proud to the exterior of the home, usually made of aluminum or vinyl with vents on either side. Click here to see our Garden Window options.

Glazing - The glass portion of a window. In modern windows this usually comprises an insulated unit with 2 pieces of glass sealed together.

Grid/Grill - The bar in a window or door creating the appearance of true, individual divided lites. See Simulated Divided Lites

Hinge Door – A door that swings either inside or to the outside when in operation.

Hopper Window - In contrast to an awning window, a hopper hinges from the bottom of a window and swings inward.

Insulated Glass Unit – Two panes of glass that are bonded together with a hermetic seal around the perimeter of the glass. Insulated glass unites typically also incorporate argon gas for improved energy efficiency.

Lift-and-Slide Doors - a specific door type that utilizes spacial hardware that allows for large panes of glass with easy operation, lifting and sliding the large panes into either pocket doors or stacking panels.

Low E3 - A Title 24 complaint glass coating to the interior of a insulated glass unit, the E stands for emicivity.

Nail-On Fin - For new construction or re-framed openings, the nail on fin (typically in 1" or 1 3/8") allows the installer to create a proper seal all around the window frame and attached directly to the studs in the wall. This is often why new construction is preferred when doing window installation.

Net Frame Size – the measurement of a windows opening including the frame of the window.

Patio Door - A sliding or hinging door with a single glass lite.

Pocket Doors - Sliding door panels that slide into a wall on either the left or right had side for concealment.

Privacy Glass - Glass typically used in bathroom applications, privacy glass styles vary by manufacture.

Retrofit - A window installation type that indicates a like-size for like-size replacement.

Rough Opening Sizes - The measurement of the stud to stud frame of either a door or window.

Sash - The operable or moving part of a window.

Sidelite - A fixed or operable window that sits to the left or right an entry or patio door. These often incorporate caming or privacy glass into their design.

Sill - The ledge of sill form in the bottom portion of a window.

Simulated Divided Lites - Creating the look of authentic or true divided lites, simulated divided lite simulate the appearance of individual panes of glass in a window or door

Single Hung Window - Common window operation type for many manufactures. Consists of one moving sash on the bottom and one non operating fixed sash.

SHGC - An acronym for Solar Heat Gain Coefficient. That measures the fraction of solar energy transmitted and tells you how well the product blocks heat coming into the house caused by sunlight. SHGC is measured on a scale of 0 to 1; values typically range from 0.25 to 0.80. The lower the SHGC, the more a product is blocking solar heat gain.

Stacking Doors - Typically utilized in lift and slide and moving glass wall configurations, stacking doors stack left, right or evenly, allowing for massive openings for easy indoor outdoor access. Click here to see examples.

Title 24 - In June of 2014, new energy requirements mandated by the states for remodels. Title 24 Compliance affects all aspects of home renovation in California.

Transom - A fixed or operable window that sits above an entry or patio door.

U-factor - measures how well a fenestration product prevents heat from escaping a home or building. U - factor ratings for windows generally fall between 0.15 and 1.20. The lower the U - factor is, the better a product is at keeping heat inside the building, thus is a better insulator.

WUIBS - An acronym for Wild Life Building Interface Building Standards. Homes that are located on plots that are near what Cal Fire deem as high risk fire zones have additional required specifications for exterior windows. Contact one of our sales reps for more details. Contact your cities building department to find out if your home must be in compliance.

Z-Bar - Specifically for the replacement of windows within an existing window opening, a Z-bar is a window installation type that has a exterior fin that sits to the exterior of the opening.

764 views0 comments
bottom of page