MgO Board – General Knowledge

Also known as magnesium oxide board, magnesium board, MGO panel, or magnesium oxide panel, it is a fire-resistant building material widely used in residential and commercial construction. Typically, an MGO board is a white, rectangular, solid panel made from magnesium oxide, fiberglass mesh, and other components.

Its primary function is to block or slow down the spread of flames, making it an essential part of passive fire protection systems. The board is also lightweight, easy to cut and install, and resistant to moisture, mold, and corrosion. Magnesium oxide boards are environmentally friendly, non-toxic, and highly durable, providing both safety and sustainability.

Common applications include wall cladding, ceilings, subfloors, and fire-rated partitions, where the board acts as a reliable barrier against fire, helping protect structures and occupants.

MgO boards are mainly divided into two types based on their chemical composition: MgSO4 board (magnesium sulfate board) and MgCl2 board (magnesium chloride board). They are both fire resistant, lightweight and strong.

2.1 MgSO4 Board

• Composition: Magnesium oxide, magnesium sulfate, perlite, fiberglass mesh, etc.

• Advantages: Excellent moisture resistance, corrosion-free.

• Best for: High-humidity areas, coastal regions, metal-framed constructions.

2.2 MgCl2 Board

• Composition: Magnesium oxide, magnesium chloride, perlite, fiberglass mesh, etc.

• Advantages: Cost-effective, suitable for standard interior applications.

• Limitations: Still sensitive to high humidity or metal contact, may require a soaking process to remove excess chlorides to reduce corrosion risk and surface sweating.

2.3 Key Differences

2.4 How to Choose

MgSO4 board generally outperforms MgCl2 board in high-humidity or metal-integrated projects due to corrosion resistance. MgCl2 board is suitable for cost-conscious projects under controlled conditions, but proper treatment and monitoring are essential.

👉 See all the mgo board applications

4.1 Size

The most common sizes of magnesium oxide board are 1220*2440mm (4*8ft) or 1200*2400mm, with the maximum size reaching up to 1200*3000mm (4*10ft).

Since the standard mold sizes available on the market are typically fixed at 1300*2500mm and 1300*3100mm, all other smaller sizes are cut from the 1200*2400mm and 1200*3000mm boards.

4.2 Thickness

MgO boards are available in a wide range of thicknesses, typically from 3mm to 40mm, depending on the application.

• ✅ Wall panels: commonly 8mm, 10mm, or 12mm
• ✅ Flooring panels: 18mm or 20mm
• ✅ Ceiling boards: 5mm or 6mm
• ✅ Tunnel boards: up to 40mm
• ✅ Door core panels: typically 38mm or 48mm

👉 See details for various applications

4.3 Density

MgO boards have a density range of 650–1400 kg/m³, depending on their intended use.

• ✅ Wall panels: typically 900–1000 kg/m³
• ✅ Flooring panels: 1200–1400 kg/m³
• ✅ Door core panels: 240–350 kg/m³

4.4 Surface

The standard magnesium oxide board features a smooth and flat front surface, while the back side has a slightly rough texture with a fiberglass mesh pattern.

• ✅ Sanded: The back side (or both sides) is further processed to become smoother and more even.
• ✅ Special treatment: The board surface can also be laminated with other materials such as PVC film to create decorative finishes with various patterns and designs.

👉 Click the following texts to see the high resolution pictures of different surface treatment:

• Standard board front side: smooth
• Standard board back side: textured
• Sanded board back side: sanded
• PVC laminated surface

4.5 Edge

There are a few options for edge treatment: square, bevel, tongue and groove (T&G).

4.6 Color

The standard color of MgO boards is white. However, by adding specific additives, other colors such as gray, black, and more can also be achieved.

When choosing fireproof building materials, it’s important to understand the differences between MgO board, drywall, and cement board. Each material has unique advantages and limitations that can impact safety, durability, and installation efficiency. In this section, we will compare their key features to help you make the right choice for your construction project.

6.1 Fire Resistance

• MgO Board: Highly fire-resistant and non-combustible, meeting most building codes and offering excellent protection in case of fire.

• Drywall: Provides basic fire resistance but can weaken under high heat and may not meet stringent fire safety requirements.

• Cement Board: Excellent fire resistance.

6.2 Moisture Resistance

• MgO Board: Excellent resistance to moisture, mold, and mildew, making it suitable for bathrooms, kitchens, and other damp environments.

• Drywall: Susceptible to water damage unless specially treated with moisture-resistant variants.

• Cement Board: Water-resistant and durable in wet conditions.

6.3 Strength & Durability

• MgO Board: Strong and impact-resistant, less prone to cracking or breaking, providing long-term stability.

• Drywall: Lightweight but relatively fragile, can be easily damaged by impact.

• Cement Board: Very strong and durable, but prone to cracking and edge chipping, and its weight makes handling and cutting more challenging.

6.4 Installation & Handling

• MgO Board: Lightweight, easy to cut and fix, compatible with both steel and timber structures, and allows for efficient installation.

• Drywall: Simple and fast to install, widely available, but less durable.

• Cement Board: Heavy and requires special tools for cutting and installation, making the process slower and more labor-intensive.

6.5 Quick Comparison Table

❌ When used for exterior walls, MgO boards cannot be directly exposed to sunlight, rain, and wind, as this will significantly shorten the lifespan.

❌ Chloride-based MgO boards, if poorly manufactured — with substandard materials, incorrect formulas, or insufficient curing — and without proper soaking treatment, may develop salt efflorescence in humid environments. This can corrode steel and damage other construction materials.

The main raw materials of MgO board include:

• Magnesium oxide
• Magnesium chloride or magnesium sulfate
• Perlite
• Wood sawdust
• Fiberglass mesh
• Non-woven fabric

👉 Learn more about the raw materials of magnesium oxide board

The production process of mgo board typically includes the following steps:

1. Material Preparation – Accurately measure the main raw materials according to the production formula to ensure consistency of the board.
2. Mixing – Blend the raw materials into a smooth, uniform slurry using high-speed mixing equipment.
3. Board Forming – Arrange layers of fiberglass mesh and non-woven fabric while pouring the slurry to form the board’s core structure.
4. Curing Phase I – Begin the curing process under controlled temperature and humidity to allow the board to partially solidify.
5. Demolding – Carefully remove the partially cured boards from the molds using automated equipment.
6. Curing Phase II – Continue curing at ambient conditions to allow internal chemical reactions to strengthen the board over several days.
7. Drying – Remove moisture from the boards by drying naturally under sunlight or in a controlled chamber.
8. Cutting – Cut the fully cured and dried boards into the required dimensions using industrial cutting machines.

👉 Check the whole production process here

👇 Check the production line of magnesium oxide board

The installation of mgo board is similar to other fire-resistant panels. Thanks to their lightweight structure and ease of cutting and screw-fixing, they provide excellent flexibility during construction.

Installation Process:

• Surface Preparation – Ensure the surface is clean, dry, and level before starting installation.
• Measuring and Cutting – Measure the required dimensions and cut the boards using a saw suitable for magnesium oxide boards.
• Positioning – Place the board in the desired location, aligning it properly with adjacent boards or structural elements.
• Fixing – Secure the board with screws or nails at recommended intervals, ensuring firm attachment without cracking the material.
• Joint Treatment – Fill gaps or joints with compatible joint compound or sealant to achieve a smooth, continuous surface.
• Finishing – Sand and prepare the surface for painting, tiling, or other final treatments as needed.

There are no strict limitations—construction teams can adapt standard practices or apply their own experience to determine the most efficient approach on site.

Note: Avoid prolonged exposure to rainwater during and after installation, as moisture may affect the performance of the board.

Below are typical installation methods for interior partition walls and sub-flooring systems, provided for your reference.

👉 Installation Guide for Interior Walls

👉 Installation Guide for Sub-flooring

The packaging of magnesium oxide boards typically involves stacking the boards on wooden pallets, securing them with packing straps, and wrapping them with stretch film or plastic bags that can be customized with logos. Upon request, additional edge and side protection can also be provided.

12.1 Forklift Loading

Magnesium oxide boards, after being securely stacked on pallets, are loaded into containers using forklifts for efficient and safe handling.

12.2 Pallet Placement Strategy

Since the board size often does not perfectly match the internal dimensions of the container, part of the pallets are placed vertically to better utilize vertical space, while others are laid horizontally. This alternating arrangement helps minimize empty space and maximizes load efficiency.

12.3 Less Loading Quantity Due to Container Weight Limitations

Due to the maximum payload restrictions of shipping containers, especially when transporting high-density boards such as mgo flooring boards, the actual loading quantity is often less than the calculated volume capacity. Even if there is still space inside the container, more boards cannot be loaded once the weight limit is reached.

12.4 Side Gaps & Anti-Tipping Measures

To prevent the pallets from shifting or tipping during transit, dunnage airbags are placed in the gaps between the pallets and the container walls and inflated to secure the load. For additional stability, wooden wedges or plastic blocks can also be added to the sides or base of the pallets.

12.5 Actual Loading Quantity

The loading quantity is not fixed, as each manufacturer has their own loading method. Here, we are only providing Suparna‘s loading quantity as a reference. Please note that this quantity is based on the standard magnesium oxide wallboard with a density of 1000kg/m³.

13.1 Is MgO board waterproof?

Magnesium oxide board is highly moisture-resistant, but it is not completely waterproof. It can withstand humidity and splashes, making it suitable for bathrooms, kitchens, and other damp areas when properly installed. Direct exposure to standing water should be avoided.

13.2 Can MgO boards be used for exterior applications?

Standard magnesium oxide boards are designed for interior use and should not be directly exposed to sunlight, rain, or wind. For exterior applications, protective cladding, coatings, or weatherproof systems are required to maintain durability.

13.3 Can MgO boards be used in bathrooms and kitchens?

Yes. Magnesium oxide boards are suitable for high-humidity environments like bathrooms and kitchens due to their excellent moisture and mold resistance. Proper installation and sealing at joints are recommended to ensure long-term performance.

14.4 Is MgO board banned?

No. Magnesium oxide boards are widely used worldwide and are not banned. However, the quality can vary, so it’s important to source boards from reputable manufacturers that follow standard production processes.

13.5 Is MgO board toxic? Is it safe to use?

MgO board is non-toxic, eco-friendly, and safe for residential and commercial applications. It contains no harmful chemicals like formaldehyde or asbestos.

13.6 How heavy is MgO board?

The weight of MgO boards depends on thickness, size, and density. Typically:

• Wall panels: density ranges from 900–1000 kg/m³

• Flooring panels: density ranges from 1200–1400 kg/m³

For reference, the table below uses 950 kg/m³ for wall panels and 1250 kg/m³ for floor panels to calculate approximate weights for common 1220 × 2440 mm (4 × 8 ft) sizes:

13.7 What’s the price of MgO board?

The price of magnesium oxide board varies depending on thickness, size, density, type (MgSO₄ or MgCl₂), and order quantity. For accurate pricing, it’s best to request a quotation from a manufacturer or distributor.

13.8 Where to buy MgO board?

MgO boards can be purchased directly from manufacturers like Suparna or through authorized distributors and building material suppliers. It’s recommended to buy from reputable sources to ensure quality and consistency.

13.9 How to choose the right MgO board?

Selecting the right MgO board depends on your project needs:

• For high-humidity areas or metal-framed construction: MgSO₄ board is recommended.

• For standard interior applications with cost considerations: MgCl₂ board can be used, but proper treatment and monitoring are required.

• Consider thickness, density, and surface treatment based on the installation type (wall, floor, ceiling, or fire door).

13.10 What is the HS code for MgO board?

The commonly used HS (Harmonized System) code for magnesium oxide boards is 68080000.

• Product name: Panels, flat boards, tiles, bricks, and similar articles

• Description: Made from cement or other mineral materials, bonded with plant fibers, straw, wood chips, or similar materials

Always verify the classification with your local customs authorities to ensure compliance with regulations.

There’s a growing amount of information online about magnesium oxide (MgO) boards—but much of it is scattered, inconsistent, or difficult to verify. For buyers, contractors, and new users trying to make informed decisions, this can lead to confusion and uncertainty.

As a professional MgO board manufacturer with over 20 years of experience, Suparna is committed to building a reliable, accessible, and practical knowledge base. This comprehensive guide brings together the key facts, technical insights, and industry practices related to MgO boards—from raw materials and specifications to installation methods and packaging.

Whether you’re planning a construction project, evaluating suppliers, or simply exploring building materials, we hope this page helps you understand magnesium oxide boards and how to use them effectively.

If you have any questions, suggestions, or need further details, feel free to contact us directly. We are always here to support your project and continuously work to improve this resource.