Based on the type of materials, positioning of different components, method of construction, intended purposes, etc., the common types of floors used in the building are discussed below.
1. Ledged Doors
A ledged door is formed by joining the vertical boards (battens) and horizontal supports (ledges) securely by suitable joints (Fig. 20.2). The battens are of 10–15 cm wide and 20–30 mm thick, whereas the ledges are of 10–20 cm wide and 30 mm thick. Top, middle and bottom ledges are used. Shutter is hung on T-hinges which are fixed to the ledges. This is the simplest form of door. It is used where strength and appearance are not very much important.
2. Ledged and Braced Doors
These doors are similar to the ledged doors discussed above but for the difference that diagonal members, known as the braces, are provided as shown in Fig. 20.3. The braces are generally of 10–15 cm wide and 30 mm thick. The braces provide rigidity and for this reason such doors are preferred for wide openings. The braces are usually housed in the ledges. It is to be noted that the braces should work in compression and not in tension.
Figure 20.2 Front elevation of ledged door
Figure 20.3 Back elevation of a ledged and braced door
3. Ledged and Framed Doors
In this type of doors, a framework for shutter is provided. This makes the door stronger and better in appearance as shown in Fig. 20.4. Styles are of 10 cm wide and 40 mm thick. As usual the battens and ledges are provided.
Figure 20.4 Front elevation of ledged and framed door
4. Ledged – Framed and Braced Doors
This type is similar to the one discussed above but for the difference that the braces are introduced (Fig. 20.5). As this type of door is strong and durable, this can be adopted for external use. The braces should incline upwards from the hanging side.
Figure 20.5 Elevation of ledged – framed and braced door
5. Framed and Panelled Doors
Panelled doors are mostly used. It consists of a framework in which panels are fitted. The styles are continuous from top to bottom and rails are joined to the styles. Mullions, if any, are joined to rails. The thickness of the shutter depends on various factors such as type of work, situation of the door, number of panels, etc. The thickness of the shutter is about 30–40 mm and the thickness of panels is about 20 mm. Panels are secured in position by the grooves inside the edges of the framework. Figure 20.6 shows panelled doors with panels. Moulding of panels adds to the beauty. Number and size of panels depend on the desire of the owner.
Figure 20.6 Elevation of framed and panelled doors
For small openings, single shutter may be adequate while double-leafed shutters are used for large openings.
6. Glazed or Sash Doors
When there is a need for more light in a room, glazed doors may be preferred. Partly panelled and partly glazed doors may be considered while some light is already available through glazed windows.
Usually the ratio of glazed portion to the panelled portion is 2 : 1. The glass is fixed into the rebates made in the wooden sash bars and secured by nails and putty or by wooden beads (Fig. 20.7).
In order to increase the area of the glazed portion, the width of styles above lock rail is decreased as shown in Fig. 20.7. These are known as the diminished styles or gunstock styles. Glazed or sash doors are preferred in hospitals, offices, libraries, show rooms, etc.
Figure 20.7 Fully and partially glazed and partially panelled doors
7. Flush Doors
A flush door comprises of a framework of rails and styles and covered with plywood or hardboard. There are two types of flush doors, viz., a framed flush door and a laminated flush door.
A framed flush door consists of styles, rails, horizontal ribs, vertical ribs and plywood (Fig. 20.8(a)). For ventilation purposes, holes are provided in horizontal ribs. The vertical ribs rest on rails. Hollow space is also filled sometimes by granulated cork or any other light material. In order to fix the hinges and mortise lock, hinge and lock holes are to be provided. These doors are light and cheap but weak and not durable.
A laminated flush door consists of styles, rails, laminated core and plywood (Fig. 20.8(b)). Under great pressure the laminae of wood are glued. Along with the plywood, sheets on either side are also glued to the laminated core under great pressure. Evidently these doors are heavy and durable.
8. Louvered Doors
Louvers are provided in the shutters which may be fully or partially louvered. Further the louvers may be movable or fixed. Figure 20.9 shows a movable type partially louvered door. Louvers are arranged at such an inclination that the horizontal vision is obstructed. That is the upper back edge of any louver will be higher than the lower front edge of the louver just above it. In the movable louvers, a vertical piece of timber is provided to which the louvers are attached through hinges. With this vertical piece, the movement of louvers can be performed. Louvers may be of glass or wood (Fig. 20.9).
Figure 20.8 Types of flush doors
Figure 20.9 Movable louvered doors
Louvers provide free passage of air in the closed position and at the same time maintain sufficient privacy. Such doors are preferred in sanitary blocks of public buildings, residential buildings, etc. However, the louvers should be cleaned often failing which dust may accumulate.
9. Wire-gauged Doors
These doors permit easy passage of air into the room. Further prevent movement of flies or insects. They are made of vertical and horizontal styles into which wire gauge is fixed. They may be provided on a separate frame or hung (Fig. 20.10).
Styles and rails shall be of the same size similar to other doors. The wire gauge shall be of best quality woven wire webbing. These doors may be of double-leaf type.
Figure 20.10 Elevation of wire-gauged door
10. Revolving Door
In a revolving door, a central support is provided to which four radiating shutters are fixed (Fig. 20.11). The shutter may be glazed, fully or panelled or partially panelled, or partially glazed. At the bottom of the shutters, called rubbing ends of the shutters, are rubber pieces fixed to prevent draught of air. The arrangements of shutters are made in such a way that the shutters may be folded and the opening can be closed. A revolving door simultaneously provides entrance on one side and exit on the other end (Fig. 20.11).
Figure 20.11 Revolving doors
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