Construction Materials Used In Pakistan:

The massive and beautiful buildings Different types of construction materials are used in Pakistan. Following are the important construction materials.

1. Cement
2. Sand
3. Concrete
4. Steel
5. Wood
6. Paint & Varnishes
7. Stone
8. Bricks
9. Glass

Cement:
Cement is one of the major construction materials. It acts as the binding agent for other construction materials like bricks, concrete blocks, tiles , etc, etc. the cement used for structural purposes is made from calcareous substances. In ordinary engineering works Portland cement is generally used.
Types of Cement:

• Natural cement
• Portland cement
• Blast furnace cement
• Rapid hardening cement
• Quick setting cement
• Coloured cement
• Sulphate resisting cement (SRC)
• White Portland cement
• High alumina cement

These types of cement are used in different areas of Pakistan under different circumstances. In Sargodha water contains high concentration of sulphate ions therefore to overcome difficulty we use ASTM type V cement which is sulphate resisting cement (SRC). In Karachi the air contains a lot of moisture due to which we use concrete blocks in which main component is cement. In hot areas like Sibbi and Jackobabad we use low heat cement because it has to develop its ultimate strength slowly.

Concrete:
Conrete is an artificial compound generally made by mixing lime or cement with sand water and some hard material called coarse aggregate such as stone crush, brick
The proportion in various contents of concrete is very important and the quantity of water plays an important role. A small excess or deficiency in the quantity of water reduces its strength.
Types of concrete:
Concrete is classified with respect to.

1. Structure requirement
2. Binding material
3. Purposes

Classification according to structural purposes:

• Plain cement concrete (PCC)
• Reinforced cement concrete (RCC)
• Prestressed concrete
• Reinforced brick concrete (RBC)
• Fiber reinforced concrete (FRC)
• Classification according to binding material:
• Cement concrete
• Lime concrete
• Polymer concrete
• Sulpher infiltrated concrete
• High early strength concrete
• Water proof concrete

In Pakistan, Karachi and areas where humidity is very high we used concrete block instead of bricks due to efflorescence in the bricks. Because of efflorescence bricks become porous and its strength decreases.

Bricks:
It is most commonly used construction material in Pakistan. Bricks are made from clay. The earth used for making brick generaly consist of alumina and silica an varying amount, mixed with lime magnesia, iron, etc, etc. the quality of bricks depends upon the clay used. In some areas like Faisalabad, Multan and Mureedkay the clay is saline. A large amount of sulphate ions are present in the clay due to which the quality of brick decreases.
In hilly area like Murree, Gilgit, etc we use stones instead of bricks because bricks absorb a lot of moisture that they become porous and the strength decrease. In Karachi bricks are also not used. In Lahore, Multan, Hyderabad bricks are commonly used because conditions are suitable to use bricks.

Sand:
The portion of an aggregate passing the sieve No. 4 (4.76 mm) and predominantly retained on the No. 200 (74 micron) sieve is called sand. Sand is fine grains of rock. It is actually silica (SiO2).
Sand is a major construction material and it is widely used in construction. It is used in both sub and super structures. Sand is mixed with soil and used in foundations. Sand is also used in mortar (mixture of cement, sand and water), which is used as binding material and also as stucco. Sand is also a content of concrete (mixture of cement, sand, crush and water). Sand plays an important role in construction. Sand used for construction should be free from alkaline salts. If it contains alkaline salts then it may spoil masonry work. In some cities of Pakistan sand contains sulphate ions in very large amount e.g. Sargodha. In those regions we have to use sulphate resisting cement other wise sulphate ions may eat mortar and concrete.
In Pakistan different types of sands are present in different areas. In Lahore the big source of sand is ‘Ravi Sand’ and commonly used.
In Sargodha sand contains sulphate ions which are not good for construction purposes therefore we use SRC in those areas. In Karachi sand is used in large amount we use it in making concrete blocks.

Stone:
Stone provides soundness to building and used where the permanency of structure is required. Stone is more durable than bricks and it has more strength than bricks.
Important example of use of stone in ancient times is the pyramids of Egypt, the evacuated ruins of ancient troy, the remains of Greek and Roman structure, the Buddhist temples and caves in India, and many other massive and beautiful buildings found practically throughout the stone. Massiveness and strength are very closely associated with building in stone. However, the Taj of Agra is a charming example of a building which strong as well as feminine in beauty.
In hilly areas like Murree, because its availability is very easy so in those areas stones are also used in those areas where clay is not easily available. Stones are obtained from mountains and shaped them as they required.
In plain areas like Punjab and Sindh, stone is very costly and it is not locally available so it is not use instead of brick or concrete blocks. In plains stone is used in decoration of floors and walls. In decoration of floors and walls marble is most commonly used.

Wood:
Wood is commonly used in structural purposes. Wood is fibrous material in which the fibers run longitudinally through the wood section this produces a material like that has good strength. Wood is hygroscopic in nature. It absorbs moisture from air and maintain moisture content equal to that of the surrounding air. As a result it will shrink and swell depending upon the amount of moisture content.
In Pakistan wood is commonly used in building purposes. In Punjab it is used in buildings, houses for making walls. Also it is used for roofing purposes. In all areas of Pakistan wood is used for making windows and doors.
Wood used for constructional purposes is present in Sialkot, Rawalpindi, Murree and Chhanga Maanga. The wood use in construction is pine.

Steel:
It is an alloy of iron and it is a major construction material. Steel with chromium content of over 10% is known as stainless steel. Mostly steel is used to provide solid foundation to a building. for roofing purposes steel is also used. Steel is used in R.C.C. (Reinforced Cement Concrete). R.C.C. is most commonly used in roofing. In roofing steel bars are used. In most villages of Pakistan R.C.C. is not used for roofing. In those areas guarders and brick tiles are used in roofs. In our cities like Lahore, Karachi, Rawalpindi, and Islamabad and in other big cities structures of multistoried buildings are made with steel.

Paint &Varnishes:
Paints are used to preserve materials from decay due to action of moisture, heat, gases; etc, etc. paints also improve appearance of materials. The composition of paints used in different areas varies according to the atmosphere of that area.
Paints are classified as:

• Oil paints
• Water paints
• Cement paints
• Bituminous paints
• Varnishes are classified as:
• Oil varnishes
• Turpentine varnishes
• Spirit varnishes
• Water varnishes

Paints and varnishes are mostly used in cities like Lahore, Sargodha, Karachi, Faisalabad, Rawalpindi, etc. in villages and under developing areas instead of paints and varnishes other materials are used for protection of surfaces. For example in villages some people use cow dung for protection of walls.

Glass:
Glass has been expensively used in building construction. It is used in windows for insulation and decoration. Rapid advances are made in glass technology had opened up newer areas of its use in construction. Main constituents of glass are silica, potash, soda, lime, lead oxide, culet and etc.
Types of glass:

• Lead glass
• Borax
• Silicate glass
• Pyrex glass
• Annealed glass

Like steel and paints it is mostly used in cities and in developed areas.