Magnesium oxide wallboard
Encyclopedia
Magnesium oxide
more commonly called magnesia is a versatile mineral that when used as part of a cement mixture and cast into thin cement panels under proper curing procedures and practices can be used in residential and commercial building construction. Some versions are suitable for a wide range of general building uses and for applications that require fire resistance, mold and mildew control, as well as sound control applications and many other benefits. As an environmentally friendly building material, magnesia board has strength and resistance due to very strong bonds between magnesium and oxygen atoms that form the magnesium oxide molecules (chemical symbol MgO).
Magnesia boards are used in place of traditional gypsum drywall as wall and ceiling
covering material and sheathing. It is also used in a number of other construction applications such as: fascias, soffit
, shaft-liner & area separation, wall sheathing, and as tile backing (backer board) or as substrates for coatings and insulated systems such as Finish Systems, EIFS, and some types of stucco
.
Magnesia cement board for building construction is available is various sizes and thickness. It is not a paperfaced material. It generally comes in light gray, white or beige in color. Numerous versions and value of grades exist including smooth face, rough texture, utility, versatile grades as well as different densities and strengths for different applications and uses.
Presently various magnesia cement boards are widely used in Asia as a primary construction material. Some versions have been designated as the ‘official’ construction specified material of the 2008 Summer Olympic Games and some versions are used extensively on the inside and outside of all the walls, fireproofing beams, and as the sub-floor sheathing in one of the world’s tallest buildings, Taipei 101
, located in Taipei, Taiwan.
Magnesia cement is manufactured in a number of areas around the world, primarily near areas where Magnesia based ores (periclase
) deposits are mined. Major deposits are found in China, Europe, and Canada. Magnesia ore deposits in the US are negligible. Estimates put the use of Magnesia board products at around 8 million SQF in Asia alone. It is gaining popularity in the US, particularly near coastal regions.
Magnesium oxide
Magnesium oxide , or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium . It has an empirical formula of and consists of a lattice of Mg2+ ions and O2– ions held together by ionic bonds...
more commonly called magnesia is a versatile mineral that when used as part of a cement mixture and cast into thin cement panels under proper curing procedures and practices can be used in residential and commercial building construction. Some versions are suitable for a wide range of general building uses and for applications that require fire resistance, mold and mildew control, as well as sound control applications and many other benefits. As an environmentally friendly building material, magnesia board has strength and resistance due to very strong bonds between magnesium and oxygen atoms that form the magnesium oxide molecules (chemical symbol MgO).
Magnesia boards are used in place of traditional gypsum drywall as wall and ceiling
Ceiling
A ceiling is an overhead interior surface that covers the upper limit of a room. It is generally not a structural element, but a finished surface concealing the underside of the floor or roof structure above....
covering material and sheathing. It is also used in a number of other construction applications such as: fascias, soffit
Soffit
Soffit , in architecture, describes the underside of any construction element...
, shaft-liner & area separation, wall sheathing, and as tile backing (backer board) or as substrates for coatings and insulated systems such as Finish Systems, EIFS, and some types of stucco
Stucco
Stucco or render is a material made of an aggregate, a binder, and water. Stucco is applied wet and hardens to a very dense solid. It is used as decorative coating for walls and ceilings and as a sculptural and artistic material in architecture...
.
Magnesia cement board for building construction is available is various sizes and thickness. It is not a paperfaced material. It generally comes in light gray, white or beige in color. Numerous versions and value of grades exist including smooth face, rough texture, utility, versatile grades as well as different densities and strengths for different applications and uses.
Presently various magnesia cement boards are widely used in Asia as a primary construction material. Some versions have been designated as the ‘official’ construction specified material of the 2008 Summer Olympic Games and some versions are used extensively on the inside and outside of all the walls, fireproofing beams, and as the sub-floor sheathing in one of the world’s tallest buildings, Taipei 101
Taipei 101
Taipei 101 , formerly known as the Taipei World Financial Center, is a landmark skyscraper located in Xinyi District, Taipei, Taiwan. The building ranked officially as the world's tallest from 2004 until the opening of the Burj Khalifa in Dubai in 2010...
, located in Taipei, Taiwan.
Magnesia cement is manufactured in a number of areas around the world, primarily near areas where Magnesia based ores (periclase
Periclase
Periclase occurs naturally in contact metamorphic rocks and is a major component of most basic refractory bricks. It is a cubic form of magnesium oxide ....
) deposits are mined. Major deposits are found in China, Europe, and Canada. Magnesia ore deposits in the US are negligible. Estimates put the use of Magnesia board products at around 8 million SQF in Asia alone. It is gaining popularity in the US, particularly near coastal regions.
History
- Magnesia cement uses in masonry construction is ancient. It was used primarily as a mortarMortar (masonry)Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. The blocks may be stone, brick, cinder blocks, etc. Mortar becomes hard when it sets, resulting in a rigid aggregate structure. Modern mortars are typically made from a mixture of sand, a binder...
component and stabilizer for soil bricks. Magnesia has also been identified in the Great Wall of ChinaGreat Wall of ChinaThe Great Wall of China is a series of stone and earthen fortifications in northern China, built originally to protect the northern borders of the Chinese Empire against intrusions by various nomadic groups...
and other ancient landmarks. Roman cementRoman cementFor the architectural material actually used by the ancient Romans, see Roman concrete."Roman cement" is a substance developed by James Parker in the 1780s, and finally patented in 1796...
is reported to have contained high levels of Magnesia.
- In the West, Portland cementPortland cementPortland cement is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout...
has replaced Magnesia for masonry uses. However, New York City’s Brooklyn BridgeBrooklyn BridgeThe Brooklyn Bridge is one of the oldest suspension bridges in the United States. Completed in 1883, it connects the New York City boroughs of Manhattan and Brooklyn by spanning the East River...
base is made from locally mined cement, a mixture of calcium oxideCalcium oxideCalcium oxide , commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic, alkaline crystalline solid at room temperature....
and magnesia cement commonly called Rosendale Natural Cement, the only natural non-fired cement made in the US.
- Magnesia cement 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 Magnesia cement board. Florida has adopted Magnesia boards for mold/mildew resistance. It is hurricane and impact tested and approved in Miami-Dade County.
- Located in Taipei, Taiwan, Magnesia board can be found on all 101 stories of Taipei 101, currently the second tallest building in the world. Magnesia sheeting was used on the inside and outside of all the walls, fireproofing beams and as the sub-floor sheathing.
- Magnesia sheeting was the “official” specified construction material of the 2008 World Olympics buildings in Beijing, a project costing over $160 billion.
Purpose and use
- Magnesia is widely used primarily as wallboard alternative to conventional gypsum-based drywall. The Magnesia boards can be scored and snapped, sawed, drilled, and fastened to wood or steel framing.
- It can be used for interior or exterior applications.
- Magnesia boards are a good example of the advances made in construction materials to meet changes in building codes for safety and durability.
Applications
- Interior Wall and Ceiling Board
- Exterior Sheathing
- Trim Materials
- 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, Portland type Stucco and Synthetic Stuccos.
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-nutritious to mold, fungus, insects ASTM G-21)
- Impact-resistant (ASTM D-5628)
- NYC Approved (MEA # 359-02-M)
- Silica/asbestos free
- 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 (400-800 °F) required to form CaO, the starting material for the preparation of slaked lime or portlandite used in common mortar and plaster.
- Magnesia boards have been mentioned in articles about the biologically friendly construction.
Disadvantages
- Natural deposits of magnesium oxide occur primarily in China, local governments there prohibit the exportation of the raw materials for manufacturing outside China.
- Little mining of magnesium based minerals occur in the United States at this time.
- In most cases good quality magnesia board is more expensive than conventional paperfaced gypsum drywall material.
- Like all cement mixtures magnesia cements and related mixing recipes and equipment require strict controls in both the raw material going into the mixer as well as the curing process and proper waiting time for setting and handling of the fresh and semi-fresh product. Many cheaper brands cut corners making inconsistent material.
- Several different producers exist with big differences in their production and selling costs which greatly impacts on the mix design and curring process which makes each brand very different in potential uses. Even though the different brands may look and feel similar caution must be used when selecting the versions and brands for specific use since they are not all the same or usable in the same way.
- As a new kind of board material it has unique installation requirements. Each version of magnesia board needs to be installed using the manufactures recommendations to avoid installation problems.