SIPA Annual Meeting Austin
Use of Mgo Boards with the formula Mgcl2 in the SIPs industry
Experience from Denmark
Short background /Time line
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More than 1 mill sq ft MgO was sold every month in Denmark from year 2010 to 2014
Problems with the MgO boards was first time noticed Oct month year 2014
The MgO boards was used in Exterior applications mainly in “ventilated façade systems”
Byggeskadefonden (Government Insurance) issued a ban to use MgO boards 6th of
Marts 2015 - Removal cost of the Mgo boards estimate to 1 mia Danish dkr (14 millions
USD) in 82 public buildings
• The MgO damage on private building – no precise information
Findings in Denmark
(3th parts reports)
Climate conditions must be: + 84% RH - Mgcl2 formula boards with free Chloride content from 3 – 7% and
boards exposed more than > 30 days period.
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From installed to problems/findings occur seams to be between 2 – 6 years depending on free chloride %
Mgcl2 boards absorb very fast humidity from the air and gain weight + 30 % first 72 hours
Mgcl2 boards release strong corrosive “tear drops” = Chloride Ions (also called “Return Halogation”)
The free Chloride ion/ tear drops is absorbed in the wooden structure and change the property of the wood
so it can absorb up to 55% moisture (mold risk) instead of normally healthy Pine wood can absorb normally
around 20 – 23 % moisture
• The free Chloride ions corrode metal parts, such as galvanized fasteners leading to structural problems in the
structure, further aluminum windows etc are destroyed.
• The free Chloride ions dis-integrate the Mgcl2 board over time (30 days) as loss of mass is between 12 – 15%
• The permability of the Mgcl2 board is lost when the free Chloride ions close the surface of the board and
moisture will build up in the boards and in the construction and the moisture can not anymore leave as
sealed chloride surface - non permability.
How could it go so wrong/solution ?
Problem:
The Danish Building Code and the EU legal CE Marking program did not
take into consideration the chemistry of the Mgo - Mgcl2 formula
boards with free chloride content (same problem in US with IBC and
IRC)
Solution ? :
Could have been avoided testing the boards towards EN 14582:2007 or
similar ASTM testing which determine the free chloride content.