A door may be defined as a framework of wood, steel, aluminum, glass or a combination of these materials secured in an opening left in a wall for the purposes of providing access to the users of the structures. It basically consists of two parts i.e., (i) A frame and (ii) Shutter (leaf).
Types of doors Used in Building construction
Depending upon the type of material used, the arrangement of different components, a method of construction and nature of working operation. Doors can be broadly classified into different types as under:
1. Battened and Ledged Door
This is the simplest form of door commonly used for narrow openings. The doors consist of a series of vertical battens or broads usually tongued and grooved and fixed together with horizontal battens known as ledges. There are three ledges one each is fixed near the top and bottom and the third one is fixed in the middle of the shutter. The middle ledge is also known as lock ledge. The battens are 75 to 100 mm. wide and 20 mm. thick. The thickness of ledges varies from 25 to 30 mm. and generally, the middle and bottom ledge are wider than the top one. The top ledge is 110 mm. wide while the middle and bottom edges are each 175 to 200 mm. wide. The door is hung on the frame by iron hinges (called T-hinges or cross garnets) fixed on the ledges.
This type of door is recommended for W.C’s, bathrooms etc, in buildings where economy rather than the appearance is of main consideration.
2. Battened Ledged and Braced Door
This is an improved form of battened and ledged door.In this type of door two additional members are provided in the form of inclined braces between the ledges. The braces are normally housed and not tenoned into the ledges. The braces incline down towards the side on which the door is hung. In this position, they act as struts and provide increased rigidity and strength to the door. The type of door can be used for wider opening in the situation where appearance is not so important as the economy.
The size of different components of the door are as under:
i) Battens: 100 to 175 mm., wide and 20 mm., thick.
ii) Ledges: 175 to 225 mm., wide and 25 to 30 mm., thick.
iii) Braces: 125 to 175 mm., wide and having the same thickness as that of ledges.
3. Battened, Ledged, Braced and Framed Door
This type of door is considered to the superior in strength, durability, and appearance to other two type of doors mentioned above. The frame work of this type of door consists of two vertical members called stiles, three horizontal members known as ledges or rails, vertical battens and two inclined braces. The rails positioned near the top, middle and the bottom of the shutter are mortised and tenoned into the stiles. The battens are generally tongued are grooved and V-jointed. At their upper end, the battens are left into the top rail while at mid height and lower ends they go right over the middle and bottom rails. The side battens are tongued into the sites. The braces are normally housed into the rails at about 4 cm., from the stiles. In order to have this arrangement of joining, the thickness of the stiles and the top rail is kept same and is equal to the combined thickness of braces and battens.
This type of door is considered suitable for external use as well as in situations where the door is likely to be subjected to rough handling.
4. Framed and Paneled Door
This type of door is commonly provided in all types of buildings. This door consists of timber frame work of stiles and rails which are grooved on the inside to receive one or more panels. Framed and paneled doors are made in several designs to suit the functional as well as architectural requirements. The door may be single, double, three, four, or six paneled and so on. The panels can be of timber, plywood, block board or hard board. Timber panels are fixed within the grooves in the frame. However additional timber beading is also provided either on one or both sides to improve the elevation of the door.
5. Glazed or Sash Door
This type of door is used in residential as well as public buildings like hospitals, schools or colleges etc., with a supplement the natural lighting provided by windows or to make the interior of one room visible from the adjacent one Glazed or Sash doors are made in several designs. They can be glazed fully or partly. Fully glazed doors are recommended in situations where sufficient light is required through the door opening as in the case of shopping or display centers, lobbies, entrance hall etc. In the case of glazed doors normally the bottom 1/3rd height of the door is paneled and the remaining 2/3rd height is glazed. In the case of partly glazed doors, the stiles are sometimes diminished at the lock rail to improve the elevation and to permit more area of glazing in the process.
6. Flush Door
With the large scale production of plywood and face veneers, use of flush door has become very popular these days. Flush door has the pleasing appearance, simple construction, high strength and durability and cost less as compared with paneled doors. These doors are commonly used in residential as well as public buildings. Flush door shutter consists of a solid or semi-solid framed skeleton (core) covered on both faces with either plywood or a combination of cross bands and faces with either plywood or a combination of cross bands and face veneers giving perfectly flush and joint-less surface. In case commercial type plywood or face veneer is used for the face panel the door is termed as commercial type flush door.
7. Fly Proof Door
This type of door is used to check the entry of flies, mosquitoes, insects etc., into the room and to allow free circulation of air at the same time. The door consists of timber frame work of vertical stiles and horizontal rails and the opening of the panels are fitted with fine mesh galvanized wire gauge. The ground level wire is fixed by use of nails and timber beading. Generally the door opening in such a case is provided with double shutters. The shutter opening inside the room is fully paneled whereas the fly proof of wire gauge shutter opens out side the room or vice versa. Fly proof doors are commonly provided for kitchens, canteens, refreshment rooms, cupboards for storing food, sweets, meat etc.
8. Revolving Door
Revolving door provides entrance on one side and exit on other simultaneously keeping the opening automatically closed when not in use. The door is so assembled as to exclude the wind draught. This type of door is advantageously provided in places where there is a regular foot traffic of people entering in and going out of the building especially when it is air conditioned or situated in a place where strong winds blow for most part of the year. The door essentially consists of four leaves radially attached to a centrally placed million in a circular opening. The mullion or the central member is provided with ball bearing at the bottom and bush bearing at the top so as to enable the door revolve smoothly without producing jerks. The leaves and the mullion are enclosed in a vestibule. At their edges the leaves are provided with rubber pieces which fit flexibility against the inside the face of the vestibule. The attached leaves may be glazed paneled or partly glazed and partly paneled. Suck doors are commonly provided in hotels, banks, offices and other such important public buildings.
9. Mild Steel Sheet Door
This type of door is recommended for railway goods sheds, garage, go-downs etc., where high degree of protection and safety is needed. The door is normally provided with two shutters. The door shutter id fabricated from angle iron or channel section braced with the angle iron diagonal braces or with mild steel flats placed horizontally. Different members of the shutter frame or riveted or welded at the junctions. In case of riveted connection, gusset plates are necessarily used at each junction. Mild steel plates of required thickness are fixed to the shutter frame with rivets or welds. The outer frame of the shutters is provided with flat iron angle cleats for fixing the shutter to the door opening. Each cleats has a 25 mm. Φ hole in the horizontal leg for supporting the shutter on pin clamps. Two pin clamps are used for each shutter. One end of the pin clamp is embedded in masonry and the other end has a 20 mm.
Φ mild steel pin riveted or welded to the clamp. The pins clamps are so placed that top pin faces downward and the bottom pin faces upwards so that the shutter can not be removed by lifting over the pins. The pins are made to pass through the holes in the cleats of the outer frame of door shutters and that is how the shutters get supported and hence attached to the jambs.
10. Sliding Door
This type of door is considered suitable for shops, sheds, go-downs, garages etc., and in places where the use of hinges for fixing the shutter is to be avoided. Depending upon the size of the opening, and the space available on either side, the door can have single, double or more number of leaves or shutters. The door is provided with top and bottom guide rails run past the openings for a distance equal to the width of shutter so that when the door is required to be opened, the door shutter occupies a new position parallel to the wall face and clear of the openings. The shutters are also provided with locking arrangements, handles, stopper etc.
11. Swing Door
This type of door is generally provided in passages of public buildings like offices, banks etc. The door may have single shutter or two shutters. The shutters are fixed with special hinges known as double action spring hinges which hold the shutter in closed position when not in use. Since these doors are pushed open, they should have glazed shutters so as to enable the users to see the objects on other side of the door and avoid accidents. As the springs return the door with force, the glazing should preferably be carried out by use of wired glass or it should be protected by other suitable means. Such doors should not be rebated at the meeting stiles. The closing edges of the meeting stiles should be segmental. Alternatively the door shutter should have a peep hole, fixed with glass. The peep hole should be at eye level.
12. Rolling Grill Door
The design, construction and operation of rolling grill is similar to the rolling steel door in all respects except the type of shutter. In this case the grill shutter is built of aluminium alloy or steel links of 0.9 mm. thickness assembled on tubes or rods. The grills can also be made out of 8 mm. diameter mild steel or aluminium alloy round bars. The rolling grill shutter can be manufactured in a variety of designs to suit the individuals choice. This type of door is used in situations where besides protections and safety, visibility and ventilation is also desired.
In some cases like transformer rooms, insulation’s etc., certain amount of ventilation is needed through the door along with increased magnitude of protection and safety. This is achieved by providing rolling steel door with small portion of the shutter at top or bottom being made up of rolling grills. This type of door is also known as rolling shutter cum grill door.