Window & Door Glossary

Aluminum
A strong, but light weight metal, that can be narrow in frame, is resistant to corrosion and is frequently used in the production of impact windows and doors.

Architectural Style/Shape Window
Fixed windows that are available in all different sizes and shapes.

Argon Gas
Colorless and odorless gas that is less dense than air. It is used to fill the air space between glass panes to increase energy efficiency.

Balancer
Counter-weight mechanism to assist raising or lowering of a double-hung or single-hung sash

BBB
The Better Business Bureau is a nonprofit membership organization with chapters throughout North America that are “focused on advancing marketplace trust.” It promotes that mission primarily through two functions: rating businesses based on their reliability and performance, and facilitating the resolution of consumer complaints.

Condensation
Moisture that forms on a surface. This could be a result of a difference in temperature or an excess of humidity between the surface and the air.

Design Pressure
Pressure (measured in pounds per square foot or psf) required by building codes to meet wind-load requirements.

Double Hung Window
A window where both the upper and lower sash slide up and down vertically. The sashes are designed to tilt into a room for easy removal or cleaning on both sides from inside a home and lock when they meet in the middle.

Egress window
A venting window large enough to be used as an emergency exit. Check local codes for egress requirements in your area.

Energy Star Certification Program
A government-backed program to help consumers identify energy efficient products.

EPA
EPA is an acronym for Environmental Protection Agency. This is in independent executive agency within the federal government that handles matters pertaining to environmental protection.

Fenestration
Refers to any opening in a structure filled with a window, door or skylight.

Fiberglass Entry Door
Fiberglass exterior doors consist of a core of rigid insulation complete with fiber-reinforced polymer and topped with faux grain to resemble wood.

Fixed Light
Fixed light window designs are directly inserted into frames, meaning they allow light into a home rather than serving the purpose of opening and closing.

Fixed Panel
Fixed panels are the sections of windows that are inoperable panels, similar to the upper sash of a single-hung style window.

Fixed Window
Fixed windows, also referred to as picture windows, are standard non-operational windows. Therefore, fixed windows do not have operable hardware, hinges or handles. These windows allow light to move inside yet the window does not allow the outside air indoors.

French Door
A style of door that has two sections that pivot on hinges mounted on opposite sides of the door framing, opening and closing in the middle. Each door section is constructed with glass panes which can extend the length of the door or a partial portion.

Full-Frame Replacement
Existing windows are completely removed down to the studs and the new window is installed in the opening.

Glazing
Installing glass into a window or door.

Grilles/Muntins/Dividers/Bars/Grids:
Components used to simulate individual pieces of glass within a sash/panel.

Horizontal roller
A versatile window with sashes positioned side by side with a slight overlap. Tracks are built into the top and bottom of the frame to allow the window to be opened and closed horizontally.

HVHZ
HVHZ stands for High Velocity Hurricane Zones and is part of the Florida building code. This designation states building products used in the area have been tested by labs to meet elevated performance standards when subjected to powerful wind and pressure.

Impact Window
A window with a heavy-duty frame along with laminated glass that is impact-resistant. Some such windows also include specialized silicone glazing to ensure the glass does not break out of its frame. Impact windows withstand powerful forces, reduce noise pollution and safeguard the home.

Impact Door
Impact doors are those designed to endure powerful blows and remain intact when a heavy object hits it. Decorative glass insets on such doors consist of specialized glass that can withstand a powerful force before giving way.

Jamb
Window or door frame members that form the top and sides of a unit.

Laminated/Impact Glass
Even more durable than tempered glass, laminated glass is often referred to as impact resistant or safety glass as it tends to remain in place when cracked. It is held in place by an interlayer, typically of polyvinyl butyral (PVB), between its two or more layers of glass.

Low-E
An extremely thin coating of special low emissivity (low E) metallic material applied to glass pane to boost energy efficiency and block out UV rays.

Miami-Dade Hurricane Rated
According to the Florida Building Code, windows must be impact-resistant or properly protected if positioned within a mile of the coast where the wind speed hits 100 mph or higher.

Mull
The actual components used to attach two or more windows and/or door units together to form an assembly.

Mulling
The process of attaching two or more window or door units together.

Mullion
The vertical or horizontal joint between individual window or door units that form a combination.

Muntins
Bars that form the decorative grille pattern on a window or door.

NFRC
National Fenestration Rating Council is a non-profit organization that provides for fair, accurate and credible energy performance ratings for windows, doors & skylights.

Obscure glass
Glass with a texture of pattern of various degrees of opacity that limits visibility through a window or door.

PACE
Property Assessed Clean Energy is affordable financing that allows property owners to pay for upgrades that increase energy efficiency, harness renewable energy, conserve water, and protect against storms.

Pane
A single piece of glass within a window or door.

Panel
Stationary or operating portion of the door that holds the glass and is separate from the frame.

Patio Doors
Patio doors are typically Sliding Glass Doors or French Doors that provide indoor access to the patio and vice versa. Patio doors let in a considerable amount of light and fresh air.

Picture Window
A fixed/stationary window to align with the profiles of operating windows. A sash is non-operable and attached directly to the frame. Often available in significantly larger sizes than accompanying operating windows.

Sash
The operating and/or stationary portion of the window that holds the glass and is separate from the frame.

Side Light
Side lights are windows that have more of a vertical emphasis. Side lights flank a large window or a door and are fairly narrow and stationary.

Simulated divided light
Use of interior and exterior grille with no spacer between the glass panes; used to simulate the look of a window with multiple glass lites.

Single Hung Window
A window with one movable sash and raised from the bottom for ventilation.

Sliding Glass Door
A type of door that has large glass panels in a frame structure that provides entry/exit access from a room to the outdoors. This type of door allows for considerable natural light and fresh air. A sliding glass door is usually considered a single unit consisting of various panel configurations that stack neatly to allow for ultra-wide openings that can be designed to slide from left, right or center.

Solar Heat Gain Coefficient
Also referred to as SHGC, this rating refers to a window’s ability to regulate the heat coming into your home. This is different than the U-Factor rating because it refers to the heat a window lets in or blocks from the sun’s rays. A window with a lower SHGC rating will allow less radiation from the sun and, therefore, less heat.

Stationary
An area of a window or an actual window that is not designed to open.

Tempered Glass
Glass that is treated to be upwards of four times as strong as conventional glass in resisting wind loads. This glass is treated through rapid heating and then cooling to help the glass become stronger.

Transom
A non-operating window stacked above another window or door.

Threshold
The bottom area of the door frame made of wood, metal or stone that you step over when entering or exiting through a doorway.

U-Factor
Commonly used measurement of heat transmission through a window/door. The lower the U-Factor, the better the insulating value.

Vinyl
Polyvinyl chloride (PVC) material that is very durable and resistant to corrosion, rotting, peeling or chipping. Windows and doors made with this material are very easily cleaned and are resistant to insect or fungus attacks.

WBD (Wind-Borne Debris)
There are areas of Florida that are designated as wind-borne debris regions by the Florida Building Code. These areas are along the coastline and inland areas, located within one mile of the coastal mean high water line (where the wind speed is 130 mph or greater) or any location where the wind speed is 140 mph or greater.

Weatherstripping
A strip of resilient material designed to seal the window or door in order to reduce air and water infiltration.

Weep holes
Small holes placed on the exterior of a window or door that allows for water drainage.

XO/OX
The letters XO or OX identify the operation of window or door units as viewed from the exterior. The letter O stands for stationary, while the letter X stands for operating.