Have you ever been confused when talking to a window and door contractor? Window and door terms can be confusing to average homeowners, so we hope this page is a good resource!

Window & Door Terminology

Bottom rail: bottom horizontal part of a window sash

Casing or trim: exposed molding or framing around a window or door that covers the space between the frame and wall

Caulk: rubber based material used to seal cracks and fill joints to prevent water and air leakage

Coated glass: glass with a reflective exterior surface; can help protect you from UV rays

Drip cap: horizontal molding used to divert water from the top casing so that it drips beyond the outside of the frame; this can prevent water damage

Fenestration: the design and placement of window openings in a home or building

Fixed window: type of window that doesn’t open

Hinge: a moveable joint that allows a window to swing open

Hopper light: inward opening sash that is hinged at the bottom

Jamb depth: width of the window frame from the inside to the outside

Moisture barrier: a material that protects your windows and doors from water damage; polyethylene is often used

Orientation: placement of windows in regard to access, view, sun, etc.

Pane: a sheet of glass for glazing a window

PVC: a molded plastic material used for window frames and as a thermal barrier for aluminum windows

Reflective glass: type of glass that reflects the sun’s rays

R-value: measure of resistance to heat flow; the higher the value, the better the heat insulating properties

Sash: framework in which the pane of a window is set

U-value: the rate of heat flow through a building (difference between the indoor and outdoor air temperature)

Weatherstrip: flexible material used to cover the joint of a window between the sash and frame; helps reduce air and water intrusion

Weephole: small holes in the bottom edge of the storm sash to allow rain to wash away from the sill to the outside; helps prevent water damage

Heard a term that isn’t on this list? Want to learn more about these window and door terms? Contact Quality Window & Door today!