Gypsum wall boards
S.Narayanamoorthy

GYPSUM BOARDS

Synthetic gypsum

 gypsum wall board

resources

overview

What is Gypsum?

Gypsum is calcium hydrous sulphate (CaSO₄2H₂O) with a chemical composition of approximately SO₃-46.5%,CaO-32.6%,water of crystallization-20.9%. Typically occurs as rock gypsum, salenite, alabaster satin spar.

Occurrence:

We see the mineral gypsum almost as part of our everyday life. This versatile mineral is the only natural substance to get back its original chemical composition and solid form after the addition of water. The minerals information page of USGS is exhaustive and is a must for any serious reader. Plaster of Paris as well as the usage of gypsum in the agricultural sector is well known. Cement industry uses gypsum for improving the setting time of cement. This article examines some aspects of its use in the making of gypsum boards.

Typical usage:

• Gypsum wallboard systems,
• gypsum blocks

• spray able plaster intended for construction, finishing, new buildings and renovation.
  
  Additional information:
  Gypsum usually occurs with contaminations and therefore calls for careful mining. The threshold value for commercial gypsum is generally at 75%gypsum. Mining of gypsum can be both surface and in certain cases underground methods. The occurrence is widespread but the major producers are Australia, Bahamas, Canada and Mexico. North America tops in utilization and the largest gypsum quarry is in Nova Scotia, Canada.
  USGS survey of the mineral industry comes out with downloadable statistics on gypsum as well as data on world production, reserves and resources. Gypsum synthesis has very interesting information about gypsum boards and is recommended for anyone looking for additional information.
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What about synthetic gypsum?

Gypsum is one of the bulk minerals which when not available naturally is made synthetically. And the synthetic gypsum has its followers and is becoming increasingly acceptable. Mostly a by-product, it is attractive to produce synthetic gypsum. Synthetic gypsum in certain cases is replacing mineral gypsum gradually as is evident from Temple's plans. Synthetic gypsum accounted for 15% of total demands. Temple has details about formation of synthetic gypsum with diagrams. Synthetic gypsum nowadays finds universal recognition particularly where natural gypsum has its constraints. When Temple considers increasing its utilization of synthetic gypsum for wallboards from its present level of 30% to even 80%, the role of synthetic gypsum can be visualized.



The Gypsum Wallboard

The gypsum wallboard being economical and fire-resistant has found a niche in the building industry and has been around for more than 50 years in one form or another. Basically gypsum board is a loose name applied to sheet products consisting of a core of non-combustible material like gypsum and a paper exterior surfacing. Since these boards undergo complex chemical and physical changes under watery conditions, a very strict code is applied and regulated. The boards are continuously researched and updated and subjected to technological advances and find their way in a variety of applications.
The Northwest Wall and Ceiling Bureau (NWCB) is an international professional trade association serving a wide ranging membership of contractors, manufacturers, dealers (suppliers, distributors) and labor.

Would you like to know how gypsum wallboard is made? There may be no need to beyond National Gypsum .

Some important producers and locations.

Lafarge Corporation is one of the major North American producers of gypsum wallboard. Lafarge North America markets a varied range of gypsum wallboard for all types of buildings, whether domestic or commercial. It is also a benchmark product for the renovation sector. Lafarge North America products are used for partitions, interior walls, ceilings and floors.
British Gypsum
The product range include plasterboard, accessories, decorative products, fire protection boards & systems plasters metal components, ceiling tiles, acoustic & thermal mineral wool insulation, wall, floor, ceiling & encasement systems.
Japan Gypsum Board
This is the place for contacts for gypsum products in some of the Asian sources.

Gypsum in Gulf
The scenario in Gulf on Gypsum boards and resources.

Associations:

Gypsum Association
Gypsum Association established in 1930 represents manufacturers of gypsum boards in USA and Canada providing information and assistance to the construction industry. Links to major producers are available at their site American Gypsum, Celotex,G-P gypsum, James Hardle Gypsum, Lafarge North America, National Gypsum, Pabco Gypsum, Temple, USG, Westrox etc.



Resources:

• Gypsum Association has posted topical technical papers. These topics are regularly updated and call for regular look ins. The papers are a very useful resource for anyone to go into details and nuances of gypsum wallboard usage and issues connected with it.
  Downloadable brochure- key to a quiet home in PDF
  Gypsum board and Rock-Lath -Resource for details on installation, lamination, lead lining and bonding. The installation diagrams are very useful.

• Recycling - Andela Products supply recycling systems throughout the world and provide details about the equipment for recycling Gypsum board. The photographs of the equipment provide visual impact.
  Additives are added to reduce drying costs by reducing the water content of the stucco. Here is a source for anyone who may require further details.
  Thickness codeR-702-3 for Gypsum board-useable chart. This is a very useful resource to check requirements for a project. The function of the Building Inspection Department is detailed here. The resources further include details for obtaining a building permit, details on various parts of a building and even a sample site plan in PDF .
  Grab this safety data sheet in PDF. The links provide further resources and British Gypsum has come out with very useful data.
   

Overview:

Synthetic gypsum is increasingly replacing mineral gypsum and this forebodes well for the wallboard industry. The issues of sagging and thickness have been addressed and progressively gypsum boards are finding very wide application base. There are already definitive guidelines, technical assistance and information base. The role of the Gypsum Association and information dissemination of major producers has brought about an increasing awareness of the gypsum wallboard application.