What do the Great Wall of China and ancient Roman bathhouses have in common? Both were constructed with cement containing MgO. MgO stands for Magnesium Oxide, a naturally occurring mineral compound, found in metamorphic rock deposits.


Today, MgO is used to construct some of the toughest SIPs on the market. But don’t confuse MgO panels with standard gypsum drywall – it’s in a class by itself. It’s ok if you know zero about MgO; it’s just now gaining popularity in the U.S. after approval for construction use in 2003. European builders have been using magnesium oxide panels for years in walls, floors, exterior sheathing, and more (they’re ahead on everything, aren’t they?). MgO is an excellent substrate for SIPs because it is:


  • Fire resistant (UL-approved, ASTM-tested)
  • Moisture, mold, and mildew resistant
  • Extraordinarily durable (the Great Wall is still standing strong)
  • “Green” and eco-friendly plus no asbestos or silica
  • Easy to work with: Go ahead and cut, drill, and affix to other surfaces (it’s ideal for lamination)
  • Available in many sizes, colors, and laminations


What’s not to love? New York and New Jersey have caught on; they’re heavy users of MgO SIPs. The Sunshine State has deemed it hurricane-tested and -approved (the impact ratings combined with mold and mildew resistant make MgO SIPs ideal for coastal buildings). Now, I won’t lie to you: Magnesium oxide panels are slightly more expensive than conventional SIPs. However, MgO panels boast a lower life cycle cost because of their durability and longevity (again, think of the Great Wall).


In my work with custom lamination, I’ve seen excellent results when bonding MgO board to EPS (expanded polystyrene) using approved structural adhesives. Many established SIP manufacturers I work with have run lamination testing for their customers, and the magnesium oxide board performs perfectly.


The Panel Man wants to know, what has your experience been with MgO panels? If you want to learn more about magnesium oxide SIPs, contact me. I can recommend a few established suppliers I have personal experience with.




Varying thickness of MgO board.

Varying thickness of MgO board.





Dow XPS Foam Core and 1/2 inch MgO Board

Here, 1/2 inch MgO board covers Dow XPS foam - it's the perfect pairing!



Did You Know?

MgO SIPS were heavily used in constructing most of the 2008 World Olympics buildings in Beijing which totaled over $160 billion!

6 Responses to “Get to Know MgO for SIPs Applications”

  1. john says:

    Great web site. Very helpful and informative…

  2. The Panel Man says:

    Hi John, thanks for checking out the site! I’m glad you found my first post informative. I look forward to sharing more info.

  3. [...] paneling solutions to today’s better option: MgO (magnesium oxide) sheathing. I wrote about MgO in my first post as a viable SIPs component in building. Now, I’m on my MgO soapbox again because I think it’s a [...]

  4. [...] Happy New Year, Panelman readers! To start off 2011, I’d like to share exciting news about magnesium oxide board (MgO) in a structural insulated panel (SIP) application. I think this year, MgO SIPs may gain serious ground as a mainstream building material. If you’d like to learn more about MgO SIPs, check out my earlier post, here. [...]

  5. Gale Harold says:

    Hi Panelman,

    Any chance you can help me get a supplier for MgO board for use in Ecuador? I’m working on a large SIPS friendly project and plan to do the laminating here. Thanks.

  6. Seymour Schatz says:

    Please send me a list of MgO SIP suppliers. I live in Madeira Beach,Florida.

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