The same trim or casing is always used around the windows as around the doors, and when the box or ground casing, or, if there is none, the edge of the pulley stile, is flush with the plaster, the finishing of the windows is exactly the same as around the doors, except that the window trim usually stops on a "stool." The stool is most frequently made of the shape shown in Figs. 94,95 and 97, being rebated to set over the wood sill. In the better class of work it is usually 1 1/8 inches thick, and should be wide enough to stop the casings. Many architects prefer to tongue the stool into the back of the sill about } inch below the top of the latter, as shown in Figs. 96, 98 and 103. When this is done the stop bead is carried across the top of the stool as shown. Where jamb casings are required (see Section 93) the latter method makes perhaps the neatest finish, but in thin walls where there are no jamb casings the author prefers the former method, as it gives a wider stool. Under the stool a moulding or board called the " apron " is always placed to cover the ground or rough edge of the plaster, and also to help support the stool. The apron should be at least 3½ inches wide.
When the box casing (see Section 93) does not come flush with the plaster, jamb casings (sometimes called " linings" or "sub-jambs") are necessary to finish between the architrave and the frame, as shown in section in Fig. 98. The jamb casings are usually made of plain boards and the inner edge is generally just flush with the plaster. When a deeper recess is desired, however, the architrave may be set against the back of the jamb casing, as shown at A, Fig. 244, but this requires additional grounds, and is not as good a method as the more common one shown in Fig. 98. In a thin wall the stop beads may be brought flush with the casings when greater width is required, as at B. If the width of the jamb casing exceeds 6 or 7 inches it will look and stand better if paneled. Very often the jamb casings are splayed, as shown in Fig. 246 (a Colonial example), and occasionally they are moulded their full width, as shown in Fig. 245. This finish is especially appropriate to deep mullioned windows.
Panel Backs. - In thick walls, whether solid or furred for shutters, the portion of wall between the window sill and the floor is often made of less thickness so as to form a recess to the floor. The inside of this wall is then generally paneled between the jamb casings, although it may be plastered and finished with a base and apron. Windows recessed in this way are said to have "panel backs." With panel backs the architraves and jamb casings are carried to the floor and finished the same as around the doors. Two very simple panel backs are shown in Fig. 247, while Fig. 246 shows a section and partial elevation of a window with panel back, paneled jambs and inside shutters. The jambs, box casings and stop beads should always be of the same wood as the architrave or casing.