Is anyone using Magnesium Oxide Board in place of OSB. I heard it was stronger, more water resistant and cheaper considering less finish work needed.


David Wilson

David,

Magnesium oxide is a great alternative to OSB, plywood, gypsum board, and tile backer board.  It is water resistant, mold/mldew resistant and fire resistant.  If you need information about people who have used magnesium oxide board, please let me know.

Paul
[email protected]

Paul,

please send the info on where i can get this material. do you have any reading material on this or web site i can get info???
also, is there a dealer in georgia??

thanks,

michael

LINK

bbcgeorgia

Just use Georgia Pacific Densglass Silver or Gold Sheathing. It works better than OSB or plywood. It's easily obtained everywhere and so the cost is down also. There's also a company here in Canada that uses a composite resin of waste plasitcs and wood fiber (plastic wood?).

I have spoken with reps form several companies about using this product here at Villa Lagoon which is a Gulf Coast hurricane proof waterfront house. I feel sure that we will use this product for walls and ceilings but don't know from whom yet. I suggested to several of them that they form an alliance to promote and educate.

I have made a web page that lists all the suppliers that I have found and links to their sites:
link

Magnesium Oxide Wall and Ceiling Material Suppliers

Follow along on our construction journal to see what brand we use and how it goes for us. You can also see storm photos on our site that show why we will not use gypsum board.

hurricane proof? a pretty strong statement!

Ya'll better watch out, when is blows over, Dick Mills might call you a liar!

Man shouldn't put GOD to the test by such statements

That's Dick "YOU ARE OUT OF LINE" Mills, to you! ;)

Dick Mills

Yea, I agree, hurricane proof is a strong statement, but hey...it is also a statement of optimism (sp?) as I see it.

Since Hurricane IVAN's eye went directly over my house and we suffered no damage...didnt even loose the roof ( I researched that before making my roofing decisions) ...while  my yard was full of about 3 or 4 other people's  houses all broken into pieces...took 3 days of back-hoe work to get the debris to the street in piles....I am thinking that  this place of mine  is hurricane proof as far as any storm dished out so far.

Even w/ all the windows locked, and shuttered, inside from the force of IVAN, [b]my big Venetian glass chandelier[/b] spun with such force that all the topmost decorative glass flourishes were slung all to one side. I have left them like that as reminder of the force of the air pressure changes. Hurricanes have lots of mini-tornadoes around the eye.

Inside I used no sheetrock, only tongue-in-groove boards for wall s and ceilings. Concrete floor and Weathershield windows and doors that open OUT, so the force closes them tighter.

The hurricane broke off all the J&L Dade County rated shutters on the south side and I never saw them again (goodbye 7 grand)...but the DAC-ART walls and the seacoast upgrade Weathershield windows held strong and tight.

After IVAN, Pensacola TV came over and did a special about my place as it was in such contrast to the devastation all around us. The water level was half-way up the length of my floor to ceiling windows but we only took in one half inch...that was from the dryer vent that I forgot to plug w/ a plumber's pressure test expansion plug. It was under the water level.

This stuff I have built with is some strong-ass stuff :o)

BTW--a sample of Dragonboard MgO board came in the mail today. If you tap it on your teeth, it feels like porcleain. It is totally white, looks like the inside of an albino Kit-Kat bar and is very strong. I am sure that this will become the standard for building down here for anyone with any sense....gypsum board is for idiots in a hurricane zone, IMHO.

I do not know why this snap-shots code (below) is inserting iteslf, it is not on my screen even in the edit panel. It is a search helper application we were experimenting w/ as a web page creation tool add-on to thumbnails the other day...guess I had better do an uninstall.


 <script src="http://shots.snap.com//client/inject.js?site_name=0" type="text/javascript"></script><script src="http://shots.snap.com//client/inject.js?site_name=0" type="text/javascript"></script>

Concrete cottage;

 

Hate to be a "doubting Thomas", but do you have any pictures of the waterline halfway up the floor to ceiling?

That would mean the windows were at least 4ft. below water?

It's hard to believe that with the storm surge and hydraulic pressure exerted upon the windows , that your house was a reverse aquarium.

It would mean that ; not only were the windows water proof, but the attachment to the structure was waterproof as well.

It looks like Hardie isn't too keen on the idea of Magnesium Oxide sheets competing with their products.

AC386-1007-R1—Fiber-reinforced Magnesium-oxide-based Sheets. A new criteria is proposed for fiber-reinforced magnesium-oxide-based sheets with various end uses. click here for responses

Here is the proposal: ac386

And, to be fair, Magnesium Oxychloride cements are very strong, but if they get wet the Magnesium Chlroide can leach out of them which degrades the integrity of the cement.  Not to mention that magnesium chloride salts are very corrosive to metal that comes in contact with the salt.

Dick Mills

According to concrete cottage ....

 "I am sure that this (Magnesium Oxide Board) will become the standard for building down here for anyone with any sense....gypsum board is for idiots in a hurricane zone.

and according to DM it doesn't fair so well when wet,

I am still waiting for CC's  photos with the waterline 1/2 up the wall, it looks like it was an attempt to promote his website , rather than a valid claim

I am pretty sure that we will go with Magnum Board from www.magnumbp.com . Dan Armstrong of Magnum Building Products has been very helpful. He's regional to us and that helps.

Two of the suppliers have taken pieces of their wallboard and run a rope thru a hole in it and left them submerged for months. They pull them up out of the lake every so often and do some on-the-spot primitive hardness tests, etc...and at least visually, cant see any change in the product.

I am not too concerned here with possible leaching of Magnesium Ch if that happens, cause for one, I wont have much, if any metal below the wallboard and if there is THAT much water...the salt alone would be corrosive enuf, plus , and that much water will be washing stuff to ground level anyway. If I were using steel studs, that might be different.

How does one insert photos in this forum ?

I am interested in using Magnesium Oxide Board. Did you get any responses to your query?

Is there a company that produces SIPs with magnesium Oxide Board? Can someone answer the discrepency about wet and leaching and waterproof - conflicting information. What about in places that have a significant amount of seasonal rain year round like the Pacific Northwest? Is leaching and soil contamination a potential problem? Is there a significant cost difference between OBS and MOB?

Thanks so much - I'll call next week. Our build is not for another couple of years, but I want to make sure I have all the necessary information before I lay my money down on the last home. I know that we'll going to build an sip home, and, right now, learning about the various types of skin possibilities and which will be best for our home and its specific climate is one of my projects.

If I put down 3/4" Magnesium Oxide board on my joists and fasten them do I have a structural subfloor?

Another question - could I use it to replace OSB or plywood as structural sheathing on a roof?

Our lab is presently testing MgO SIPs. At this time we are testing adhesive spread rates for SIPs with an EPS core and MgO skins on one and both sides of the SIP. I mention one side and both sides since we are also evaluating SIPs with different skins, such as OSB/MgO, Fiber Cement (FC)/MgO, and OSB/FC. We have not started compressive load or rack/shear testing because we are not through assessing adhesive spread rates.

We have reviewed reports on MgO skins with internal steel (C channel) studs from a MgO supplier; however, this information, while interesting, is not the same as traditional SIPs with an adhesive bond to an EPS core; and therefore, of little value to SIP manufactures. I am not aware of any ICC or other code reports for MgO; although, it would seem reasonable that manufactures would be pursuing those types of testing. Those interested in this on going testing and information may contact me off line at:


Matt B. Phelps, P.E., R.S.
SIP Engineering & Testing, LLC
201 CR 138
Hutto, Texas 78634
512/670-9400 (o)
512/670-9407 (f)
512/748-8199 (m)
Email: [email protected]

Your information, while interesting, dose not provide us any new information. It is nice to see that a manufacture knows their product; however, we need information on how to build SIPs from MgO and performance data on SIPs with MgO skins. Most professionals tend to discount manufactures claims unless they are accompanied with engineering data or certifications such as ICC. In searching the ICC data base, I find they do not have any certifications for MgO in any form.

If you have engineering data such as the modules of elasticity, bending moment, compressive, tensile, or shear strength on your MgO skins, please share this information with us.

Thank you,

Matt B. Phelps, P.E., R.S.
SIP Engineering & Testing, LLC
201 CR 138
Hutto, Texas 78634
512/670-9400 (o)
512/670-9407 (f)
[email protected]
www.apec-llc.com
www.advancedgreenproducts.com
www.sipengineeringtesting.com

 

This is some of the available info on one of the MGO boards.
Hope this is helpful.  
 

Data Sheet

 

Physical Characteristics

 

Flexural modulus	.93 x 106 psi	ASTM D-6109
Flexural strength	8935 psi	ASTM D-6109
Shear Strength	391 psi	ASTM D-6109
Flame spread	0	ASTM E-84
Smoke development index	0	ASTM E-84
Smoke density	None	ASTM E-622 not required
Moisture content	8%	GB/T 160-1997 (outside US)
Impact resistance	1.65 ft. lbs./in. of notch	GB/T 7019-1997 (outside US)
Thermal insulation	R= 1.2 / inch	GB/T 7019-1997 (outside US)
Fungus / Mold	Non-nutrient	ASTM G-21
Smoke	Non-toxic	ASTM E-662

 

Impact Testing

The tests listed below were performed on 10mm (7/16”) thick material per ASTM D-5628, using a 10 lb (4.5kg) dart with a hemispherical end.

Drop Height (inches)	Unclamped Edges	Clamped edges
12	Hairline cracking	Hairline cracking
6	Superficial cracking	Superficial cracking

 

Design Recommendations

Uniformly Distributed Floor Loading (lbs/sq ft). Joist spacing center-to-center in parentheses.

Panel	L/360(12”)	L/360(16”)	L/360(24”)	L/240(12”)	L/240(16”)	L/240(24”)
10mm(7/16”)	94psf	40psf	12psf	142psf	60psf	19psf
14mm(9/16”)	251psf	106psf	32psf	378psf	160psf	47psf

 

Load for Maximum Allowable Stress

Panel	12” o.c.	16” o.c.	24” o.c.
10mm (7/16”)	1366 psf	751 psf	336 psf
14mm (9/16”)	2609 psf	1470 psf	654 psf

These recommendations based on a maximum allowable flexural stress of 1000psi.

 

Panel Shear

10mm (7/16”) panel	461 # / ft
14mm (9/16”) panel	646 # / ft

These recommendations based on a safety factor = 4.0

The use of a “T” shaped spline ½ inch high with 1 inch wings on both sides is recommended for panels 14mm (9/16”) thick, or heavier, used for sub-flooring.

 

 

 

 

Comparison

 

Comparison of Sheathing Panel Materials

 

All mechanical values based on ½” nominal thickness or material and 16” joist spacing.

Value	This Board	Cement Board	Plywood	Gyp Wallboard	Gyp Sheathing
Flame spread	0	0	High	15	0
Smoke developed	0	0	>50	0	0
Combustibility	Non-comb	Non-comb	Burns	Facing burns	Non-comb
Wt. lbs /sq. ft.	2.4	3.0	1.6	1.9	2.4
Insect resistant	Yes	Yes	No	No (paper)	Yes
Mold & mildew resistant	Yes	Yes	No	No (paper)	Yes
Distrib. load l/360 psf	43	22	65	Low	12
Distrib. load l/240 psf	64	32	90	Low	16
Max. distributed load	260	73	120	Low	65
Water absorption (sat)1	<20%	24%	30-40%	Disintegrates	Not given
Thermal insulation R	1.2/in	0.8/in	1.25/in	0.9/in	1.1/in
Bend radius (min)	7 ft	Flat only	8 ft	10 ft	30 ft
Racking Strength (ult)2	1840#/ft	Not given	250#/ft	200#/ft	540#/ft

 

¹ Value after 24 hour immersion.  Gyp. Wallboard not permitted in exterior application.

² Racking strength given is not for design purposes. Use safety factor of at least 4.0.

 

Pin Puncture Test (2 inch diameter pin)

 

Time to penetrate under load

Fire Exposure (mins)	7/16 Board	½ GWB Firecode	9/16 Board	58 GWB Firecode
10 mins.	20# 30 secs.	20# 14 secs.	20# no break 30 secs	20# no break 30 secs
15 mins			20# no break 30 secs	20# 3 secs
20 mins			10# 7 secs.