User:Findoutwhy

Magnesium oxide use in building construction

In addition to its other uses, boards made of magnesium oxide have been found to be a versatile and useful material in residential and commercial building construction. It is suitable for a wide range of general building board usages and for applications requiring a fire rating as well as mold and mildew control.

Derived from its chemical formula; Mg - magnesium, O - Oxygen (oxide), Magnesium oxide is commonly called, MgO (pronounced: Em, Gee, Oh). Magnesium oxide boards is used in the place of the typical gypsum drywall as wall and ceiling cover material or sheathing. It is also being used in a number of other construction applications such as: fascias, soffits, shaft-liner & area separation wall sheathing, and as tile backing (backer board) or substrates for coatings and insulated systems such as Direct-Applied Finish Systems, EIFS, and stucco.

MgO board for building construction is available is various sizes and thickness. It is a non-paper-covered material and generally light gray, white or beige in color. It comes in various grades, such as smooth finishes, rough textures, and utility grades.

As a construction material MgO board has several attractive characteristics: fire resistance, moisture resistance, mold and mildew resistance, and strength.

Presently MgO board is widely used in Asia as a primary construction material. It was the ‘official’ construction specified material of the 2008 Summer Olympic Games and was used in extensively on the inside and outside of all the walls, fireproofing beams and as the sub-floor sheathing in the world’s tallest building, Taipei 101, located in Taipei, Taiwan.

MgO is manufactured in a number of areas around the world, primarily near areas where MgO ore (magnesite) deposits are mined. Major deposits are found in China, Middle East, and Canada. MgO ore deposits in the US are negligible. Estimates put the use of MgO board products at 8 million SQF in Asia alone. It is gaining popularity in the US, particularly near coastal regions.

History
Magnesium oxide’s use in mostly masonry construction is ancient. It was used primarily as a mortar component and stabilizer for soil bricks. MgO has also been identified in the Great Wall of China and other ancient landmarks. Roman cement is reported to have contained high levels of MgO.

In the West, Portland cement has replaced MgO for masonry uses. However, New York City’s Brooklyn Bridge base is made from locally mined cement, a mixture of calcium oxide and magnesium oxide commonly called Rosendale Natural Cement, the only natural non-fired cement made in the US.

MgO boards were approved for construction use in the US around 2003.

Due to its fire resistance and safety ratings, New York and New Jersey were early adopters of MgO board. Florida has adopted MgO for its mold/mildew resistance. It is hurricane and impact tested and approved in Miami-Dade County.

Located in Taipei, Taiwan, Magnesium oxide can be found on all 101 stories of Taipei 101, currently the tallest building in the world. MgO sheeting was used on the inside and outside of all the walls, fireproofing beams and as the sub-floor sheathing.

MgO sheeting was the “official” specified construction material of the 2008 World Olympics buildings in Beijing, a project costing over $160 billion.

Purpose/Use
MgO is widely used primarily as wallboard alternative to gypsum-based sheet rock. The boards can be scored and snapped, sawed, drilled and fastened to wood or steel framing. It can be used for interior or exterior applications.
MgO boards are a good example of the advances made in construction materials to meet changes in building codes for safety and durability.

Applications include:
·Fascias
·Soffits
·Shaft-liner & area separation wall board
·Tile backing (backer board) and underlayment
·Substrates for coatings and insulated systems such as: Direct-Applied Finish Systems, EIFS, SIPS & Stucco

Advantages
·Ratings and Testing Fire-resistant (UL 055 and ASTM-Tested and A-Rated)
Waterproof (Freeze/Thaw-Tested for 36 months)
Mold/Fungus/Bug Free (Non-nutrient to mold, fungus, insects ASTM G-21)
Impact-Resistant (ASTM D-5628)
NYC Approved (MEA # 359-02-M)
Silica/Asbestos Free
Florida Hurricane Tested
STC-Rated 53-54
·Can be used in the place of traditional drywall or cement boards. No special tools required. ·Hard non-absorbent surface – No paper. ·Can be used in applications like cement-based siding. ·Available in colors. ·Environmentally friendly – It is removed from ore at about 25% of the temperature (400-800F) required to form CaO, the starting material for the preparation of slake lime or portlandite used in common mortar and plaster.

Disadvantages
Natural deposits of magnesium oxide occur primarily in China, local governments there prohibit the exportation of the raw materials for manufacturing outside China.

Safety
SAF-T-DATA(tm) Ratings
Health Rating: 2 - Moderate
Flammability Rating: 0 - None
Reactivity Rating: 2 - Moderate
Contact Rating: 1 - Slight
Lab Protective Equip: GOGGLES & SHIELD; LAB COAT & APRON; VENT HOOD; PROPER GLOVES
Storage Color Code: Green (General Storage)

References
1. Concrete Cottage, http://www.concretecottage.com/Magnesium-oxide-boards.htm
2. Ceilings and Walls, Robert Thomas, October 2007 http://www.wconline.com/CDA/Archive/BNP_GUID_9-5-2006_A_10000000000000194720
3. Substance Distributing, Inc. http://substanceproducts.com/products/content/all-about-mgo
4. Mallinckrodt Baker, Inc., http://www.jtbaker.com/msds/englishhtml/m0182.htm