How We Count Windows

Single Hung Windows

Windows that have one (single) sash that slides up and down.
Double Hung Windows

Windows that have both (two) sashes that slide up and down.
Plate Windows

A large, single pane of glass.
Plate Windows

A large, fixed single pane of glass that is non-operable.
Transom Windows

A window that is non-operable or fixed, often above or near a door or another window.
Hexagon/Octagon

A fixed window that is designed to be non-operable and consist of a glazed frame or a non-operating sash within a frame, cut in the form of a six or eight-sided polygon.
Suspended Grids/False Grids

The grid that "creates" the panes is suspended or between sheets of glass. You can't feel them with your hand.
Removable Grids

Window grids that can be added or taken from the window frame as desired. Usually attached on the room side of the glass.
Glider and Sliding Glass Windows

Open by sliding horizontally along a track for ease-of-use.
Awning, Hopper, Projected Windows

A window consisting of one or more sash hinged at the top or bottom which project outward or inward from the plane of the frame.
Casement Windows

A window consisting of one hinge to open from the side (adjacent to the jambs), which project outward or inward.

Two Single/Double Hung Windows

Two of these windows placed side-by-side are counted as two.
Single Windows With Transom

A full-size window with a transom counts as two.
Sliding Glass Doors

These large glass panels are counted as two windows.
French Doors

Doors with glass panes throughout its length, typically with one or two doors that swing open.
Fixed/Non-Removable Grids

Windows with non-removable obstructions making window look and feel like individual pieces of glass.
Two Casement Windows

Two window sashes hinged to open from the side (adjacent to the jambs), which project outward or inward.

Three Double Hung Windows

Three double hung windows grouped together are counted as three windows.
Bay Windows

A window or series of windows forming a bay in a room and projecting outward from the wall (in this case 3 panes of glass).
Storm Windows

Additional windows installed outside of the primary windows for insulation.

Garden Windows

Specialty window that protrudes from the house, may have shelves, angled glass for plants.
Skylights

Specialty window that is installed in the roof for natural light.
Jalousie Windows

A series of glass slats set in a track. The slats are operable.
Glass Block Windows

Thick blocks of glass, between 2 and 4 inches thick, that are inset into a window frame.
Stained or Leaded Windows

Colored glass used for making decorative windows through which light passes.