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103:) 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 740,000 square metres (8 million square feet) in Asia. It is gaining popularity in the US, particularly near coastal regions.
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Little mining of magnesium based minerals occurs in the United States or Europe, and is not thought profitable other than for higher value ceramic applications such as refractory brick preparations (so called magnesia refractories). Most building projects involving low cost MgO board will inevitably
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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 achieve
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Several different producers exist, with big differences in their production and selling costs, which greatly impacts on the mix design and curing process. This makes each brand very different in potential uses. Even though the different brands may look and feel similar, caution must be used when
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Located in Taipei, Taiwan, magnesia board can be found on all 101 stories of Taipei 101, currently the eighth 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
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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
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Most often the boards are produced by using Sorel cement (Magnesium oxychloride), resulting in a slightly hygroscopic product that can produce a problem called "crying boards" when applied in too humid climate. Example:
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Magnesia is widely used primarily as wallboard alternative to conventional gypsum-based drywall and plywoods. The magnesia boards can be scored and snapped, sawed, drilled, and fastened to wood or steel framing.
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Natural deposits of magnesium carbonate (Magnesite ore) occur in China and this is calcined to produce magnesium oxide. Local governments in China prohibit the export of raw materials needed to manufacture MgO
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Energy efficient – magnesite calcines at approx 780 Celsius, compared to over 1,400 Celsius required to form traditional
Portland cement or calcium oxide, the starting material for the preparation of
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Magnesia cement board for building construction is available is various sizes and thickness. It is not a paper-faced material. It generally comes in light gray, white or beige. Grades include
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Boards tend to have quite unique installation requirements. Each version of magnesia board needs to be installed using the manufacturer's recommendations to avoid installation problems.
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Various magnesia cement boards are used in Asia as a primary construction material. Some versions have been designated as the official construction-specified material of the
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has strength and resistance due to very strong bonds between magnesium and oxygen atoms that form magnesium oxide crystals (with the chemical formula MgO).
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high early strength using magnesium oxychloride cement technologies, which make the board more susceptible to water weakening and inconsistent material.
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The chloride in Sorel cement is relatively immobile, but in some cases can produce a corrosive environment for embedded fasteners and steel studs.
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Magnesia boards are a good example of the advances made in construction materials to meet changes in building codes for safety and durability .
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replaced magnesia for masonry uses in the 20th century when energy was cheap (see energy efficiency) and mold infection was poorly understood.
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Substrates for coatings and insulated systems such as direct-applied finish systems, EIFS, SIPS, Portland type stucco and synthetic stuccos.
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Comparable in cost to cement board made from
Portland cement, with numerous advantages over that material for wet applications.
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Magnesia boards have been mentioned in articles about biologically friendly construction and risks of mold infection.
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selecting the versions and brands for specific use since they are not all the same or usable in the same way.
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In most cases, good quality magnesia board is more expensive than paperfaced gypsum drywall material.
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covering material and sheathing. It is also used in other construction applications such as fascias,
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Can be used in applications like cement-based siding subject to using water-proof coating systems.
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Magnesia cement is manufactured around the world, primarily near areas where magnesia based ore (
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Can be used in the place of traditional drywall or cement boards. No special tools required.
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component and stabilizer for soil bricks. Magnesia has also been identified in the
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Magnesia cement use in masonry construction is ancient. It was used primarily as a
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Magnesia cement boards were approved for construction use in the US around 2003.
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China
Expands Scope of Prohibited Category under Export Processing Trade
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Mold/fungus/bug free (non-nutritious to mold, fungus, insects ASTM G-21)
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Hard non-absorbent surface – using fibreglass backing – with no paper.
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However, some projects continued to use magnesia. New York City's
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is reported to have contained high levels of magnesia.
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base is made from locally mined cement, a mixture of
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Fire-resistant (UL 055 and ASTM-tested and A-rated)
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223:Water-resistant (freeze/thaw-tested for 36 months)
259:or portlandite used in common mortar and plaster.
42:Magnesia boards are used in place of traditional
20:Magnesium oxide wallboard (10 mm thickness)
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204:Tile backing (backer board) and underlayment
201:Shaft-liner and area separation wall board
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56:exterior insulation finishing systems
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280:rely on Chinese or Indian materials.
142:and magnesia cement commonly called
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186:Exterior wall and fencing board
183:Interior wall and ceiling board
346:Robert Thomas (October 2007).
229:Impact-resistant (ASTM D-5628)
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232:NYC approved (MEA # 359-02-M)
120:and other ancient landmarks.
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395:Passive fire protection
27:, more commonly called
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217:Ratings and testing:
33:building construction
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348:"Ceilings and Walls"
252:Available in colors.
235:Silica/asbestos free
86:2008 Summer Olympics
58:, and some types of
335:Periclase at Mindat
118:Great Wall of China
390:Building materials
189:Exterior sheathing
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155:Miami-Dade County
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350:. Archived from
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144:Rosendale cement
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238:STC-rated 53-54
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166:Purpose and use
136:Brooklyn Bridge
129:Portland cement
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25:Magnesium oxide
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44:gypsum drywall
37:Magnesia board
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270:Disadvantages
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140:calcium oxide
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127:In the West,
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356:. Retrieved
352:the original
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178:Applications
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122:Roman cement
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46:as wall and
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257:slaked lime
67:smooth face
384:Categories
358:2009-01-03
322:References
316:Clay panel
276:elsewhere.
212:Advantages
161:sheathing.
96:, Taiwan.
90:Taipei 101
101:periclase
79:versatile
310:See also
29:magnesia
198:Soffits
195:Fascias
107:History
75:utility
48:ceiling
114:mortar
94:Taipei
60:stucco
52:soffit
300:Dokk1
92:, in
77:and
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