The frame is the stationary portion of a window that encloses either the glass (direct glaze) or the sash (operating or stationary) and consists of the following parts:
1. HEAD JAMB: The top frame member.
2. SILL: The bottom frame member.
3. SUB-SILL: The supplemental member used under most awning and casement units as an additional sill with the primary
purpose being to hold multiple units together at the sill.
4. SIDE JAMB: Side or vertical frame members.
5. JAMB EXTENSION: The addition onto the standard jamb to adapt a window unit to deeper wall thicknesses, in most cases will be factory applied unless specified otherwise.
6. BRICK MOULD OR FLAT CASING: The exterior trim member applied to the side jambs and head jamb on wood units. Often used to secure the window to the wall opening.
7. BLIND STOP: The frame member on a double hung window located between the jambs and the casing. The blind stop forms a rabbet that supports either a storm sash or screen.