Types of Glass and its Engineering Properties for Use in Construction

There are various types of glass used in construction for different purposes. Engineering properties and uses of these glass is discussed in this article.

Glass is a hard substance which may be transparent or translucent and brittle in nature. It is manufactured by fusion process. In this process sand is fused with lime, soda and some other admixtures and then cooled rapidly. Glass is used in construction purpose and architectural purpose in engineering.

Engineering Properties of Glass

• Transparency
• Strength
• Workability
• Transmittance
• U value
• Recycle property

Transparency of Glass

Transparency is the main property of glass which allows the vision of outside world through it. The transparency of glass can be from both sides or from one side only. In one side transparency, glass behaves like mirror from the other side.

Strength of Glass

Strength of glass depends on modulus of rupture value of glass. In general glass is a brittle material but by adding admixtures and laminates we can make it as more strong.

Workability of Glass

A glass can be molded into any shape or it can be blown during melting. So, workability of glass is superior property of glass.

Transmittance

The visible fraction of light that passing through glass is the property of visible transmittance.

U value of Glass

U value represents the amount of heat transferred through glass. If a glass is said to be insulated unit then it should have lower u value.

Recycle Property of Glass

Any glass can be 100% recyclable. It can also be used as raw material in construction industry.

Types of Glass and their Uses in Construction Works

The types of glass used in construction are:

• Float glass
• Shatterproof glass
• Laminated glass
• Extra clean glass
• Chromatic glass
• Tinted glass
• Toughened glass
• Glass blocks
• Glass wool
• Insulated glazed units

Float Glass

Float glass is made of sodium silicate and calcium silicate so, it is also called as soda lime glass. It is clear and flat so, it causes glare. These glasses are available from 2mm to 20mm thickness ranges. They have a weight range of 6 to 36 kg/m2. These are used as shop fronts, public places etc.

Shatterproof Glass

Shatterproof glass is used for windows, skylights, floors etc. Some type of plastic polyvinyl butyral is added in its making process. So, it cannot form sharp edged pieces when it breaks.

Laminated Glass

Laminated glass is the combination of layers of normal glass. So, it has more weight than normal glass. It has more thickness and is UV proof and soundproof. These are used for aquariums, bridges etc.

Extra Clean Glass

Extra clean glass has two special properties, photocatalytic and hydrophilic. Because of these properties, it acts as stain proof and gives beautiful appearance. Maintenance is also easy.

Chromatic Glass

Chromatic glass is used in ICU’s, meeting rooms etc. it can control the transparent efficiency of glass and protects the interior from daylight. The chromatic glass may be photochromic which has light sensitive lamination, thermos-chromatic which has heat sensitive lamination and electrochromic which has electric lamination over it.



Tinted Glass

Tinted glass is nothing but colored glass. A color producing ingredients is mixed to the normal glass mix to produce colored glass which does not affect other properties of glass. Different color producing ingredients are tabulated below

Coloring ion	Color
Iron oxide	Green
Sulphur	Blue
Manganese dioxide	Black
Cobalt	Blue
Chromium	Dark green
Titanium	Yellowish brown
Uranium	yellow

Toughened Glass

Toughened glass is strong glass which has low visibility. It is available in all thicknesses and when it is broken it forms small granular chunks which are dangerous. This is also called as tempered glass. This type of glass is used for fire resistant doors, mobile screen protectors etc.

Glass Blocks

Glass block or glass bricks are manufactured from two different halves and they are pressed and annealed together while melting process of glass. These are used as architectural purpose in the construction of walls, skylights etc. They provide aesthetic appearance when light is passed through it.

Glass Wool

Glass wool is made of fibers of glass and acts as good insulating filler. It is fire resistant glass.

Insulated Glazed Units

Insulated glazed glass units contains a glass is separated into two or three layers by air or vacuum. They cannot allow heat through it because of air between the layers and acts as good insulators. These are also called as double glazed units.

Different Types of Doors Used in Building Works

There are various types of doors that are used in building works. A door is an accessible barrier which is provided in a wall opening to give an access to the inside of a room of a building. The internal portions of a building are connected by doors.

Types of Doors Used in Building Works

Doors are classified into several types, based on

1. Placing of components
2. Method of construction
3. working operations
4. Construction material used

Types of Doors based on Placing of Components

Based on the arrangement of door components, the doors are classified as following,

1. Battened and Ledged Doors

• Battens are vertical bonds which are having grooves are attached together by horizontal supports called ledges as shown in below figure.
• General Dimensions of batten are 100-150mm width and 20-30mm thick.
• General dimension of ledges are 100-200mm width and 25-30mm thick.
• This type of battened and ledged doors suitable for narrow openings.

2. Battened, Ledged and Braced Doors

• To make more rigid, braces are provided diagonally in additional to battens and ledges as shown in figure.
• Braces are having 100-150mm width and 25-30mm thickness are preferable.
• Braces should place upwards from handing side, then they acts as struts and take compression.
• These type of doors can be used for wider openings.

3. Battened, Ledged and Framed Doors

• For the simple battened and ledged door, frame work is provided in the form of two verticals, known as stiles.
• Stiles are generally 100mm wide and as far as thickness is concerned, the thickness of stile should be equal to the combined thickness of ledge and batten. Preferably 40 mm.

4. Battened, Ledged, Braced and Framed Doors

• In this type, the door made up of battens, ledges, stiles and braces. So, it is more rigid.
• The braces are connected diagonally between the ledges, at about 40mm from the stiles.

Types of Doors based on Method of Construction:

Based on the method of construction, the doors are again classified into 5 types and they are:

5. Framed and Panelled Doors

• These are very strong and will give good appearance when compared to battened doors. These are the widely used doors in almost all types of buildings.
• Stiles, vertical members and rails, horizontal members are grooved along the inner edges of frame to receive the panels.
• The panels are made up of timber or plywood or A.C. sheets or glass.
• These doors may be single leaf for narrow openings and double leaf for wider openings.
• Minimum width of stile should be 100mm and minimum width of bottom and locked rail should be 150mm.

6. Glazed Doors

• Glazed doors are generally provided in interior wall openings or in hospitals, colleges etc.
• The interior of room is visible through glazed doors and light also passes through glazed portion of the door.
• These may be fully glazed or partly glazed and partly panelled. Glass panels are provided for glazed doors.

7. Flush Doors

In flush doors, a solid or semi-solid or core portion is covered on both sides with plywood or face veneer. Now a days these type of doors are widely used because of good appearance, economic, ease of construction and greater durability.

There are two types of Flushed doors:

Solid Core or Laminated Core Flush Door

• The core part in solid core flush door consists of core strips of timber which are glued under high pressure condition. Similarly in the laminated core, battens of 25mm width are glued under high pressure.
• These doors consists of wooden frame with stiles and rails for holding the core.
• Finally plywood sheets or face veneer and cross-bands are glued under pressure on both side of doors.

Hollow core and cellular core flush door

• In this case also stiles and rails are provided for frame. But, a minimum of two intermediate rails should be provided.
• The inner space of door consists of equally space battens of width 25mm each. Other space is called void space which does not exceed 40% of the area of door.
• Here also face veneer and cross-bands are glued under high pressure.

8. Louvered Doors

• The louvers permit natural ventilation when the door is closed and also provide privacy in the room.
• These are generally used for toilets of residential and public buildings.
• The door may be fully louvered are partly louvered.
• Louvers are made up of timber or glass or plywood and these may be either fixed or movable.

9. Wire Gauged Doors

Wire gaged doors permits natural ventilation and restrict the entry of flies, mosquitoes, insects etc.. These doors are commonly used in hotels, restaurants and for cup boards containing eatables.

Types of Doors based on Working Operations

The doors are classified on the basis of working operations as:

10. Revolving Doors

Revolving doors are only provided in public buildings like museums, banks, libraries etc., because of constant visitors. It consists mullion at its centre to which four radiating shutters are attached.

11. Sliding Doors

In this type, with the help of runners and guide rails the door slides to the sides. The door may have one or more sliding shutter depending up on the opening available.

12. Swing Doors

In this case, the shutter is attached to frame by double action spring which helps the shutter to move inwards as well as outwards.

13. Collapsible Steel Doors

Collapsible steel doors are generally used for workshops, sheds, warehouses etc.. It acts like a steel curtain which will opened or closed by horizontal pull or push. Vertical double channel units of (20x10x2 mm) are spaced at 100 to 120 mm thick and are braced flat iron diagonals 10 to 20mm wide and 5mm thick.

14. Rolling Steel Shutter Doors

Rolling steel shutter doors are commonly used for warehouses, garages, shops etc.. These are very strong and offer proper safety to the property. The door consists frame, drum and a shutter of thin steel plate inter locked together. A horizontal shaft is provided in the drum which helps to open or close the shutter.

Types of Doors based on Materials:

Doors are made up of wood, glass, metals. Wood doors are already discussed in the 1t classification and glass doors are nothing but glazed doors. Types of Metals doors are described below.

15. Mild Steel Sheet Doors

• The door frame is made up of angle or T-sections.
• Shutter is made up of frame of angle of iron, having 2 verticals at least 3 horizontal.
• Mild steel plates are welded to the shutter frame.

16. Corrugated Steel Sheet Doors

These are same as mild steel sheet doors, but in place of mild steel sheet corrugated steel sheet is welded.

17. Hollow Metal Doors

Hollow steel sections are used to make these doors. The rails and stiles etc., are strengthened by welding small T or I sections inside.

18. Metal Covered Plywood Doors

• This type of door is a composite construction of hollow metal door and wood door.
• The door is encased in tight fitting sheet metal, having tightly folded joints to exclude air so that the core of the door does not ignite. So, it acts as fire proof.