Magnesium oxide boards
MgSO4 boards for walls, ceilings, floors, substrates and fire-door cores.

A professional manufacturer of glass-magnesium inorganic fireproof board — chloride-free MgO boards for walls, ceilings, floors, sheathing and fire doors.
13 products on one chloride-free magnesium oxysulfate core — from standard wall and ceiling boards to subfloor, structural sheathing, exterior backer board, fire door cores and finished decorative panels.
MgSO4 boards for walls, ceilings, floors, substrates and fire-door cores.
Compressed magnesium oxysulfate sheathing with OSB-like screw holding, 12 and 15 mm.
Waterproofed MgO board with EPS particles for render, tile and cladding backer walls, 8–12 mm.
Finished panels with an MgO core: HPL, aluminium and acoustic slat surfaces.
All decorative panelsMgO board is magnesium oxide bound with a magnesium salt. Older boards use magnesium chloride, which draws moisture from the air and releases chloride that corrodes steel screws and framing. Every Jiafeng board uses magnesium sulfate instead.
0.012%chloride ion content of Jiafeng MgSO₄ boards, tested to ASTM C871
MgO board vs. fiber cement boardOur laboratory tests every shipment and issues an in-lab test report. Standard documents cover GB, EN, ASTM and ISO methods. Our laboratory
Plus dimensions and tolerances, linear variation and water absorption (sections 5, 7, 8, 9).
Behaviour of the board in a vertical tube furnace at 750 °C (E136-19a).
Chloride ion content below 0.012% — the test that separates sulfate from chloride boards.
Resistance to repeated freezing and thawing (modified method).
Nail-head pull-through (section 15) and falling-ball impact (section 21).
Compression indentation of the board surface (section 7).
Sag of a supported board in high humidity (section 14).
Bond strength of tile mortar to the board surface.

Jiashan Jiafeng Decorative Materials is a professional manufacturer of glass-magnesium inorganic fireproof board in Jiaxing, Zhejiang — about 70 km from the ports of Shanghai and Ningbo. Automatic feeding and mixing, sheet forming, automatic demoulding and a UV coating line keep quality stable from raw materials to finished boards.
Exported to Japan, Singapore, United States, United Kingdom, Australia and other countries.
About JiafengLining and partitions, subfloors, structural sheathing for SIP and modular buildings, exterior backer walls, fire doors, clean rooms and finished interiors.
MgO board consists of three elements: magnesium oxide, a magnesium salt and crystal water. The main component is magnesium oxide (MgO), which is completely non-flammable. Depending on the grade we add bamboo or wood fibre, perlite or EPS particles as filler, and reinforce both faces with glass-fibre mesh.
There are two main types of salt used in MgO board: magnesium oxychloride (MgCl₂), which carries a risk of steel corrosion, and magnesium oxysulfate (MgSO₄). Jiafeng makes new-generation chloride-free MgSO₄ boards; the chloride ion content of our boards is 0.012% (ASTM C871).
MgO board is moisture resistant, but long exposure to water affects its properties and causes hydrothermal expansion. Outdoors it should be covered or coated. We can waterproof boards in the factory on request — by adding waterproofing elements to the mix or sealing with UV paint. Normal MgO board absorbs about 20% water; waterproofed board absorbs less than 10%.
Thickness from 3 to 30 mm, with a maximum size of 1220 × 3050 mm (some grades up to 3660 mm long). Standard sizes are 1220 × 2440, 1220 × 2745 and 1220 × 3050 mm; other sizes, colours and edge profiles (square, tapered, T&G, shiplap) are made to order.
Yes. Tell us the product, thickness and application and we will send samples. Our laboratory tests every shipment and can provide in-house test reports; third-party reports are available on request.

Where magnesium oxide boards are used — fire-rated walls, wet rooms, floors, sheathing — and how they compare with gypsum, plywood, cement board, concrete and brick.

Composition, fire and water performance, applications, environmental impact and cost of fiber cement board and magnesium oxide board, side by side.

What MgO board is made of, how it is manufactured, and why it is safe in fire, damp and daily use — plus the chloride issue and how sulfate boards avoid it.
Send the board type, thickness, size and quantity. We reply with a quotation, loading plan and lead time — usually within 2 hours on working days.
Request a quotation
We use your details only to answer your inquiry. See our privacy policy.