MGO Fire-resistant linings and protective layers within assemblies

 

MGO (magnesium oxide) fire-resistant linings and protective layers are key functional components in construction, industrial facilities, and modular buildings. Based on magnesium oxide (MgO) as the core material, they are formulated and structured to provide Class A non-combustibility, high-temperature stability, thermal insulation, fire resistance, and structural protection within wall, ceiling, duct, equipment, and other assembly systems. They represent a mainstream solution for modern passive fire protection and structural safety.

 

MGO Fire-resistant Linings / Protective Layers: Inorganic non-combustible boards, coatings, or prefabricated modules made primarily from magnesium oxide (MgO), combined with magnesium chloride / magnesium sulfate binder, vermiculite, perlite, fiberglass mesh, etc., cured and formed. They are installed inside or on the surface of walls, ceilings, ducts, steel structures, and other assemblies to form a continuous fire barrier.

Core Position: The first line of passive fire defense in assembly systems - non-combustible, heat-absorbing, fire-blocking, smoke-resistant, while also providing structural strength, moisture resistance, weather resistance, and construction compatibility.

 

 

Typical Formulation of MGO Fire-resistant Board / Lining

 

Component	Proportion	Core Function
Magnesium Oxide (MgO)	50%–70%	Main refractory phase with melting point ~2852°C; forms a stable crystalline skeleton at high temperatures; non-combustible, non-melting, non-dripping
Magnesium Chloride / Magnesium Sulfate	15%–25%	Binder that reacts with MgO to form Sorel Cement, providing high strength and density after curing
Vermiculite	5%–15%	Expands 2–3 times at high temperatures to form an insulating expansion layer, sealing gaps and blocking heat transfer
Perlite	5%–10%	Lightweight and porous; improves thermal insulation and reduces thermal conductivity of the assembly
Fiberglass / Mesh Cloth	3%–8%	Enhances flexural and impact resistance; prevents cracking at high temperatures and maintains structural integrity
Modifiers (Waterproof / Anti-halogen)	1%–3%	Improves water resistance and anti-halogen performance for humid environments

 

Fire Resistance Mechanism (Four Core Effects)

• Non-combustible (Class A1)As an inorganic mineral, MgO has no ignition point, no flame spread, no melting or dripping, meeting the highest non-combustible grades of EN 13501-1 A1 and ASTM E136.
• Endothermic CoolingCombined water and magnesium hydroxide (Mg(OH)₂) in the material decompose at 200–400°C, releasing large amounts of water vapor. This absorbs heat, lowers substrate temperature, dilutes combustible gases, and isolates oxygen, significantly slowing fire development.
• Thermal Barrier & Expansion SealingVermiculite expands to fill gaps at high temperatures, forming a dense insulation layer. The MgO crystalline skeleton remains stable above 1200°C, blocking thermal radiation and conduction to extend fire resistance.
• Low Smoke & Non-toxicProduces extremely low smoke density and no toxic fumes (no formaldehyde / asbestos) under fire conditions, ensuring safe evacuation.

Application Forms in Assemblies

Wall Assemblies (Most Common)

• Light-gauge Steel / Wood Stud Partitions: MGO boards used as double-sided linings or single outer linings, paired with rock wool / glass wool insulation to form 1–4 hour fire-resistant walls (e.g., firewalls in hotels, malls, data centers).
• Modular Building Wall Panels: Composite of MGO board + insulation core (PU / rock wool), factory-prefabricated and on-site assembled, integrating structure, fire resistance, insulation, and moisture resistance with fire resistance up to 3+ hours.
• Exterior Wall Siding / Lining Board: Replaces OSB and gypsum board as a continuous fire-resistant lining, improving overall building fire rating and compatible with various finishes (paint, tile, cladding).

Ceiling Assemblies

• Fire-resistant Ceiling Liners: MGO boards installed directly on joists or used as backer boards for gypsum board to form 1–2 hour fire-resistant ceilings for machine rooms, electrical rooms, and public areas.
• Shaft / Duct Shaft Lining: MGO boards line shaft interiors to block vertical fire spread and meet building code fire separation requirements.

Steel / Concrete Protection

• Steel Structure Fire Cladding: MGO boards or strips wrapped around steel beams and columns, replacing traditional fireproof coatings with faster installation, higher strength, and better weather resistance, achieving up to 3 hours fire resistance.
• Concrete Component Protection: Used as linings in tunnels and industrial furnaces to resist high temperatures and chemical erosion, extending service life.

Duct & Equipment Protection

• Industrial Duct / Chimney Linings: MGO refractory coatings or prefabricated liners withstand 1000–1600°C high temperatures, resistant to slag and thermal shock, used in metallurgy, chemical, and power industries.
• Equipment Fire Protection Layers: External linings for high-temperature equipment and storage tanks providing passive fire and physical protection.
• 3.5 Special Assemblies
• Fire Door Core / Liner: MGO boards used as internal filler or surface liners for fire doors to improve fire integrity and thermal insulation.
• Floor / Slab Fire Underlayment: MGO boards laid over structural slabs as fire and sound insulation underlays, suitable for underfloor heating and heavy-duty applications.

 

Key Performance Indicators

Fire Performance

• Non-combustible Grade: A1 (EN 13501-1) / Class A (ASTM E136); flame spread index = 0, smoke density = 0.
• Fire Resistance Rating: 1h / 2h / 3h / 4h under standard assemblies.
• High-temperature Resistance: Sustained use at 800–1200°C, short-term up to 1600°C, without melting, collapse, or cracking.

Structural & Physical Properties

• Strength: Flexural strength ≥ 12 MPa, compressive strength ≥ 30 MPa, superior to gypsum board and fiber cement board; can bear loads and fix attachments directly.
• Density: 0.8–1.2 g/cm³, lightweight to reduce assembly load and ease transport and installation.
• Moisture & Water Resistance: Water absorption ≤ 15%; stable in short-term humidity without expansion or deformation, suitable for bathrooms, kitchens, basements.
• Dimensional Stability: Low thermal expansion and contraction; no cracking or warping under high-temperature or wet-dry cycles.

Construction & Compatibility

• Workability: Can be cut, drilled, nailed, and glued with standard carpentry tools; installed similarly to gypsum board, short construction period, low labor cost.
• Compatibility: Compatible with light-gauge steel, wood studs, steel structures, concrete, insulation materials, and various finishes (paint, tile, stone).
• Eco-friendliness: No asbestos, formaldehyde, or VOCs, compliant with LEED and green building standards.

 

5. Typical Assembly Systems & Fire Performance

System 1: Light-gauge Steel Double-sided MGO Fire Partition

• Assembly: 75mm steel studs + double-sided 12mm MGO boards + 75mm rock wool (density ≥100kg/m³) in cavity
• Fire Resistance: ≥3 hours (ASTM E119 / GB/T 9978)
• Application: Firewalls, machine room partitions, hotel guestroom separators, data center divisions

 

System 2: Prefabricated Modular Composite Wall Panel

• Assembly: 12mm MGO outer liner + 100mm PU / rock wool core + 12mm MGO inner liner (fully composite)
• Fire Resistance: ≥2 hours, with thermal insulation (λ≤0.035W/m·K) and sound insulation (≥45dB)
• Application: Modular buildings, temporary structures, container houses, rapid-assembly offices

 

System 3: MGO Cladding for Steel Structure Protection

• Assembly: H-section steel column / beam + double-layer staggered 15mm MGO boards + special fire-resistant fasteners
• Fire Resistance: ≥3 hours, replaces thick fireproof coatings with smooth finish and ready for decoration
• Application: Industrial workshops, shopping malls, high-rise steel buildings

 

System 4: Exterior Wall MGO Fire-resistant Lining System

• Assembly: Structural wall + waterproof vapor barrier + 12mm MGO lining board + insulation layer + exterior finish
• Performance: Overall Class A non-combustible exterior wall, improving building fire safety for all climate zones

 

 

Profile

 

Advantages vs. Traditional Fire Protection Materials

 

Property	MGO Fire-resistant Lining	Gypsum Board	Fiber Cement Board	Fireproof Coating
Non-combustible Grade	A1 (Highest)	B1	A2	Substrate-dependent
Fire Resistance	1–4h (flexible assemblies)	0.5–2h	1–2h	1–3h (thick coating)
High-temp Stability	Stable at 1200°C	Softens at 800°C	Cracks at 1000°C	Peels at high temp
Structural Strength	High (load-bearing)	Low (fragile)	Medium	None
Moisture Resistance	Excellent	Poor	Medium	Fair
Installation Efficiency	High	High	Medium	Low
Eco-friendliness	Non-toxic, no asbestos	Contains binders	Average	Contains solvents

 

Application Fields & International Standards

Core Application Areas

• Commercial Buildings: Malls, hotels, offices, hospitals, schools (firewalls, partitions, ceilings)
• Industrial Buildings: Workshops, warehouses, equipment rooms, electrical rooms, data centers (steel protection, fire compartments)
• Modular / Prefabricated Construction: Precast wall panels, container houses, temporary buildings (integrated fire-resistant structures)
• Infrastructure: Tunnels, subways, bridges (fire-resistant linings, protective layers)
• Residential Buildings: High-rises, villas (fire partitions, kitchen / bathroom liners, floor underlays)

Major International Standards

• Europe: EN 13501-1 (reaction to fire), EN 1365-1 (fire resistance)
• USA: ASTM E119 (fire resistance), ASTM E136 (non-combustibility), UL 263
• China: GB 8624 (burning performance), GB/T 9978 (fire resistance), JC/T 2329 (MGO board standard)

 

Wall Board Factory

 

Company Advantage (Why choose us)：

We specialize in quality control and consistency of MgO products. We have actively participated in the development of ASTM standards related to MgO products. We have joined hands with the China Magnesium Industry Association (CMMA), the Magnesium Oxide Building Products Association (MgOBPA) of North America, and the Magnesium Oxide Association (MOCA) to jointly promote the popularization of magnesium oxide cement products in the construction sector.

We are committed to the research, development, production and sales of green building products. Striving to be a leader in industrial and technological development, we aim to be a reliable supplier of high-quality products and services.

 

Certificate

 

FAQ:.

Q: Can you do custom product?

A: Yes, we can make boards according to your requirements.

Q:.What is your packing?

A:Plywood or solid wood pallets.

Q:.Can I get a discount?

A:If your quantity is more than our MOQ, we can offer a good discount.

 

Packing and Shipping:

 

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