Exteiror Sheathing2019-11-15T18:12:56+00:00

Magnesium Cement Board

ROCKMAX magnesium cement board is a fireproof sheathing design for semi-exposed exterior wall.  which is made from reinforced magnesium oxysulfate cement, grade E mesh fiber and waterproof polymers. ROCKMAX is leading chloride free mgo passed all the durability test to EN 12467(fiber cement sheathing standard). It is fireproof and cost effective sheathing, highly recommend for tile,brick,stone veneer substrate,ETICS underlayment, alumium curtain wall substrate and stucco substrate etc.

A1 FireproofWill not release toxic gas when it is burning
High StrengthBending strength 12mm < 18 Mpa
DurableTested to BS EN 12467 category A for exterior sheathing
Dimension stableDimension changes <0.3% in exterior wall
Waterproof coatingWater absorption speed is lower than mgo board or fiber cement board
Cut and screw easilyScore and snap cut by utility knife
Material Safety meet EN REACH requirement, exclude 191 kind of harmful substance

Fire Resistance

Mold Resistance


Easy cut and work with

Impact Resistance

Heat Resistance


Building Safe

Moisture Resistance

Insect Resistance


Health Safe

Magnesium Cement Board Technical Data Sheet

ParameterResultTest Standard
Density<1050kg/m3BS EN 12467 -2012
Bending strength12mm< 18 MpaBS EN 12467 -2012
Water absorbing by weight/24 hours< 15%BS EN 12467 -2012
Water impermeability  after 24h, water gauge 5 cmLack of leakageBS EN 12467 -2012
Shrinkage and expansion rate(outdoor)<0.3%ASTM C 1186-08
Thermal conductivity<0.22W/(m·K)ASTM C 518-10
Asbestos or formaldehydeNoneEN REACH
Fire ResistantA1EN ISO1182 &1176
Chloride content<0.03%ASTM C 871
Wet – dry          50 cycles
Heat rain          50 cycles
Freeze-Thaw      100 cycles
Warm water        56 days
Strength remain>75%EN 12467
Category A  Class 3
Surface burning and smokeClass A  Flame Spread<25
Smoke Develop<25
ASTM E 84-12

Magnesium Cement Board Applications:

ApplicationExterior sheathing with EIF & StuccoETICS backer board
Exterior backer board for brick veneerExterior backer board for curtain wall
Exterior backer board for alumium composite panelExterior backer board for tile
Exterior fire resistant system
Accessory(exterior wall)Steel frame or wood frameSelf drilling screw
Self adhesive mesh tapeFlexible jointing compound
Drained cavity batten,wall warpInsulation, mortar, mesh net, waterproof paint
LimitationCan not use for exterior wall without waterproof paint
Can not serve high tempreture > 70’cCan not store outside without raincoat

Magnesium Cement Board Loading Capacity



Quantity 1 x Pallet

Loading capacity in 20ft CNT

Bulk Load In 20ft CNT

12mm x 1220 x 2440


67 pieces

540 pieces

 650 pieces

12mm x 1220 x 2750


67 pieces

540 pieces

 600 pieces

12mm x 1220 x 3050


65 pieces

520 pieces

 600 pieces

● Other thickness and dimension can be customized