What is Gypsum?

Gypsum is a rock like mineral commonly found in the earth’s crust, extracted, processed and used by man in construction or decoration in the form of plaster and alabaster since 9000 B.C.

It is a soft white or grey mineral consisting of hydrated calcium sulphate. It occurs chiefly in sedimentary deposits and is used to make plaster of Paris and fertilizers, and in the building industry.

Uses of Gypsum• Be added to some bread and dough mixes as a Calcium source and baking

aid.• Be used as a filler and fi re retardant in plastic products.• Be used in Portland cement and special cement products for set• and expansion control.• Be a source of Calcium and Sulphate Sulphur for plant growth.• Be used as a modelling material for tooth restorations.• Be an ingredient in many patching compounds.• Be used with glass to fabricate large, lightweight architectural• decorations.• Be used as a mold material to fabricate custom body parts for trucks• and automobiles.• Be an aid in juice extraction of some fruits and vegetables.

In Home Interiors:A. Plasterboards•Plasterboard is used for partitions and the lining of walls, ceilings, roofs and floors. The properties of plasterboard can be modified to meet specific requirements, such as fire resistance, humidity, resistance, impact resistance, etc.

B. Decorative Plaster•Plaster powder, mixed with water, is used to create an effective and aesthetically-pleasing lining for brick and block walls, and for ceilings. •Gypsum's adaptability in application lends itself to molding and shaping.

C. Building plaster•Gypsum plaster is used for walls and ceilings.

D. Plaster blocks• Gypsum blocks are used for partitions and Gypsum tiles for ceilings.E. Gypsum-based self-leveling screeds• Anhydrite or Alpha-Hemihydrates are used in the production of self leveling

floor screeds.F. Gypsum Fiberboards • Gypsum fiberboard is used for partitions and the lining of walls, ceilings,

roofs and floors. Standard Gypsum fiberboard offers good performance when it comes to impact resistance, sound insulation and humidity resistance.

Gypsum products propertiesGypsum is fire protectiveGypsum is non-combustible and able to delay a fire’s spread up to 4 hours.

Gypsum regulates soundWith insulation materials create quiet.They are designed to provide a physical barrier to sound, incorporate a sound break and minimize reverberation.

Gypsum acts as a thermal insulatorThanks to its low thermal conductivity, Gypsum plasterboards contribute ,together with the insulating material to the insulation of external walls and linings.

Gypsum equilibrates humidity and heat peaksGypsum is capable of storing humidity when a room is humid and automatically releasing this humidity if the indoor air becomes too dry. Plasterboards have also a “heat-storing” ability.

Gypsum is impact resistantPlasterboards, gypsum fibreboards and plaster blocks have degree of hardness equivalent to a thick wall heavy masonry construction

Gypsum is easy to install and to dismantleThe operation is fast, clean, dry and uncomplicated.

Gypsum is multifaceted, multipurpose, supple and aestheticA richness of forms can be created in plasterboard or stucco. For architects, building with gypsum products allows them to unleash their creativity within an affordable budget.

MARKET SURVEY• Gypsum Board – USG Boralo Size: 6x4 Price: Rs 325/- Thickness12.5 mm• Plaster board – Saint Gobain – Gyproco Size : 6x4 Price: Rs 340/- Thickness 12.5 mm• Sacarni Instand Gysum bondo Quantity: 5 liters Price : 750/-• Gypsum plaster / One coat plaster – o Price 4600 - 5600 per ton i.e. 4.60 or 5.60 per kg • Gypsum POP –o Price – 4200 – 5000 per ton i.e. 4.20 or 5 per kg o If buying from a wholesaler, minimum order of 25 ton has to be placed .• Sacarni POP o Weight: 25 kg bag Price: 160/-• Shreeram POPo Weight : 20 kg Price: 125/-• Gold lion (local)o Weight : 25kg Price: 140/-• Gyproc Stico Plaster / NI plastero Weight 25kg Price: 180/- (stico) and 210/- (NI)• Superfine o Weight – 20kg ( 17kg) Price: 75/-

Case study Location: Indian institute of technology, madras.

Gypsum used to create: glass fiber reinforced gypsum panel used in floors, roof, staircases, thus significantly reducing the construction of Reinforced Cement.

Development : Rapid wall Building Systems, Australia, developed a technology to make gypsum strong and water-resistant enough to be used as load-bearing walls.

This is by calcining process where glass fiber is combined with gypsum plaster to produce glass fiber reinforced gypsum (GFRG) panels.

IIT madras, in collaboration with rapid wall, have developed a technology to make GFRG panels to be also used as floor/roof, thus eliminating the use of RCC slabs. An eight-storied building, for instance, can be built using the panels as load-bearing walls, floors/roofs and staircases.

Since Water-proofing is essential for prolonged durability of the GFRG panels, especially in the case of roofs and toilets therefore, They also collaborated in the indigenous development of an excellent water-proofing material.

THE PROCESS• The building will have four units — two with a carpet area of 269 sq. are for the

economically weaker section, and another two, with a carpet area of 497 sq., are for the low-income group (LIG).

• What makes the rapid construction possible is that the panels are prefabricated and cut to desired sizes based on room sizes with openings for doors and windows.

• A panel has two skins of 15 mm thickness that are interconnected at regular intervals (25 cm). The cavities formed by these interconnections are used for several purposes — filling with concrete, and laying electrical conduits and plumbing pipes.

• For the floor/roof, the panels are placed over the vertical wall panels and the top skin of every third cavity is cut open. Steel reinforcement is placed in these cut cavities before being filled with concrete. The concrete-filled cavities tend to behave as hidden beams. The panel is then covered with a 5-cm thick concrete topping.

• Since the panels have a smooth finish, the need to plaster them (as in the case of brick walls) does not arise. The total weight of the building (dead weight) is reduced substantially

• According to the IIT researchers, tests conducted have shown that GFRG panels reinforced with concrete are also capable of resisting lateral loads caused by earthquakes.

Fly ash waterproof footing foundation

Placement of gfrg panels onto 10mm bars from plinth beam.

Placement of 10mm bars in every third cavity

Addition of concrete is added to every third cavity for reinforcement.

Stairs are made and 10mm bars are installed.

125 mm gfrg floor is placed over existing walls.

Reinforcement cage inserted to act as concealed beam

Panels for the next floor are erected and the process is repeated

After roofing, waterproofing course is provided.

Installation