Glossary - F

A Glossary of window terminology

A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z

Fixed

Non-venting or non-operable. 

Flashing

A thin strip of metal or synthetic material that diverts water away from a window or door. 

Frame

The combination of head, jambs and sill to form a precise opening in which a window sash or door panel fits. 

French sliding door

A sliding patio door, which has more substantial (wider) panel frame members giving it the look of French doors.

Face
Refers to the side of a siding or soffit panel that is showing once the panel has been installed.

Face-nailing
The action of fastening directly onto the “face” side of a panel (instead of using the nail hem slot). This practice is generally not used in siding installation.

Fascia Board
A board attached to the ends of the rafters between the roofing material and the soffit overhang. Fascia cap is the covering around that board.

Fixed Lite
A pane of glass installed directly into non-operating framing members.

Fixed Panel
An inoperable panel of a sliding glass door or slider window.

Flashing
A thin, flat material, usually aluminum, positioned under or behind J-channels, corner posts, windows, etc., to keep draining water from penetrating the home.

Furring Strip
A wooden or steel framing material, usually 1" x 3", used to provide an even nailing base. To “fur” a surface means to apply these strips.

Fusion-welded
The process of joining materials by melting them together with extreme heat (in most cases over 500ºF), resulting in the materials combining into a one-piece unit.

Fenestration
The placement (or arrangement) and design of the windows and exterior doors of a building. In Greek architecture, windows began as simple openings in temples. These openings began to contain glass in the 13th century, when clear glass was available for buildings such as Westminster Abbey. Another important shift in fenestration occurred in the 20th century when large windows became important components in commercial buildings.  

Fiberboard
A broad term used to describe wood sheet material of widely varying densities manufactured of refined or partly refined wood fibers.  

Filler
A trim piece used to provide a weatherstrip seal for the operating sash or panel on a horizontal sliding window or door.  

Finger Joint
A joint between two pieces created by machining a series of interlocking groves; used to create a longer section of wood. The joints are firmly held in place with an adhesive.  

Finish
The final, protective treatment of a surface (paint, stain, etc.).  

Fire-Rated Door
A door that is noncombustible in the average structure fire for a minimum period of time. A fire-rated door takes a certain number of minutes to burn; usually 20, 60 or 90 minutes.  

Fixed
Refers to a window or door that is non-venting or inoperable.  

Flat Door Panel
A door panel consisting of a flat piece of plywood, solid wood or other material in contrast to a raised door panel.  

Flitch
A thin piece of wood, used often as a veneer. 

Flush Door
A door consisting of a core, cross-banding and flat-face veneers, or a door consisting of a core and flat-face veneers only.  

Frame
The assembly of structural members (head, sill, jambs) used to fasten a window sash or a door panel to a structure. 

French Door
A style of door in which two panels open to provide a clear opening which is approximately twice as wide as one panel. In the 19th century, glass was being added to door construction, mainly in French and German homes, on internal doors leading to rooms containing more natural light, such as conservatories, glass houses and vestibules. 

French Casement Window
A window unit comprised of a single frame in which two sash (hinged at the side jambs) may be opened outward from the center of the frame. This creates an unobstructed opening which spans nearly the complete width of the frame.