MDF FR (Fire-retardant MDF)
Flame-retardant grade
Specify where reaction-to-fire class B-s1,d0 / GB 8624 B1 is required — shopfitting, public interiors, wall linings.
Values for the FR condition
Other MDF tempers and conditions
MDF is listed in 4 conditions; see the grade overview at MDF.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Light / ultralight MDF | Choose for weight-critical or thick non-structural parts — display props, exhibition panels, model-making, lightweight case goods. | — | 12 | — | — | 0.09 W/m·K |
FRThis page Fire-retardant MDF | Specify where reaction-to-fire class B-s1,d0 / GB 8624 B1 is required — shopfitting, public interiors, wall linings. | — | 15 | — | — | 0.13 W/m·K |
moisture-resistant, MUF resin, green-tinted | Use in humid interior service — kitchen/bath cabinetry, worktop cores, laundry furniture; still not for exterior exposure. | — | 19 | — | — | 0.13 W/m·K |
High-density fibreboard | Pick when you need maximum stiffness, edge-profile crispness and screw holding — laminate flooring cores, thin door skins, speaker baffles. | — | 25 | — | — | 0.16 W/m·K |
What is MDF FR?
MDF FR is MDF in the FR grade — specify where reaction-to-fire class B-s1,d0 / GB 8624 B1 is required — shopfitting, public interiors, wall linings. MDF FR has a tensile strength of 15 MPa (2.18 ksi), weaker than 64% of natural material grades. Elongation at break is 1% and the elastic modulus is 2.8 GPa (0.406 Msi). MDF FR has a density of 0.8 g/cm³ (0.0289 lb/in³), heavier than 70% of natural material grades.
Limitations
- Needs corrosion protection — 22/100, worse than 93% of natural material grades
- High embodied carbon — 0.85 kg CO₂/kg, worse than 76% of natural material grades
MDF FR properties
Typical room-temperature values for MDF FR; 11 are specific to this condition. Other listed values are MDF reference data and may not represent this condition. Bars are the position among natural material grades.
Physical2
MDF FR has a density of 0.8 g/cm³ (0.0289 lb/in³), heavier than 70% of natural material grades.
Mechanical10
MDF FR has a tensile strength of 15 MPa (2.18 ksi), weaker than 64% of natural material grades. Elongation at break is 1% and the elastic modulus is 2.8 GPa (0.406 Msi).
Thermal5
MDF FR is rated for continuous service to 100°C (212 °F). It conducts heat at 0.13 W/m·K (0.0751 BTU/hr·ft·°F), worse than 57% of natural material grades. Thermal expansion is 8 µm/m·K (4.44 µin/in·°F).
Electrical2
MDF FR is an electrical insulator with a dielectric strength of 2.5 kV/mm (63.5 V/mil) and a resistivity of 1×10⁷ Ω·m.
Chemical & Environmental1
Corrosion resistance is poor (22/100), worse than 93% of natural material grades.
Sustainability4
Producing a kilogram of MDF FR takes about 12 MJ of energy and emits 0.85 kg of CO₂ — more than 64% of natural material grades. Typical recycled content is 30%.
Manufacturability2
MDF FR's machinability is very good (82/100, better than 53% of natural material grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with MDF FR
Is MDF easy to machine?
Machines like a soft isotropic solid — carbide or diamond-tipped router bits, high spindle speed and low feed give crisp profiles; the resin-laden dust is abrasive and respirable, so dust extraction and tool-life allowance are mandatory.
Can MDF be welded?
Not weldable; joints are made with PVA/PUR adhesive, dowels, confirmat screws or knock-down hardware, and screws into edges need pilot holes to avoid splitting.
Can MDF be formed, bent or molded?
Flat panels can be cold-formed only over large radii; use kerf-cutting, thin flexible MDF or postforming-grade panels for curves, and 3D-embossed doors are produced by membrane-press moulding of routed blanks.
What surface finishes work on MDF?
Faces take primer, UV lacquer, foil, melamine and veneer excellently; cut edges are porous and must be sealed with edge filler/PVA-primer or banded, and any water-based finish will raise the fibres unless the panel is sealed first.
MDF chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| urea-formaldehyde resinMUF/pMDI used for moisture-resistant and low-emission grades | 7 – 12 | 10 |
| paraffin wax emulsionhydrophobing agent | 0.4 – 1.5 | 0.9 |
| moistureequilibrium board moisture content as shipped | 4 – 9 | 6 |
| hardener / scavenger (ammonium salts, ur | 0.1 – 1 | 0.4 |
| fire-retardant salts (FR grade only)phosphate/borate loading in FR variant | 0 – 12 | 0 |
| wood fibre (cellulose/hemicellulose/lignrefined softwood/hardwood chips, sawmill residue and recovered wood | ≥ 78 (balance) | — |
MDF FR — frequently asked
What is MDF FR used for?
MDF FR is typically used for furniture, cabinetry, moulding and trim, laminate flooring core and speaker enclosures. In short: best-machining wood panel; flattest paint-ready substrate; low-cost CNC-routed panel.
What is the tensile strength of MDF FR?
MDF FR has a typical tensile strength of 15 MPa (2.18 ksi) — weaker than 64% of natural material grades. Strength varies by condition: see the 4 listed tempers.
Is MDF FR easy to machine?
Yes — machinability is rated very good (82/100, better than 53% of natural material grades). Machines like a soft isotropic solid — carbide or diamond-tipped router bits, high spindle speed and low feed give crisp profiles; the resin-laden dust is abrasive and respirable, so dust extraction and tool-life allowance are mandatory.
Can MDF FR be welded?
Not weldable; joints are made with PVA/PUR adhesive, dowels, confirmat screws or knock-down hardware, and screws into edges need pilot holes to avoid splitting.
What surface finishes work on MDF FR?
Faces take primer, UV lacquer, foil, melamine and veneer excellently; cut edges are porous and must be sealed with edge filler/PVA-primer or banded, and any water-based finish will raise the fibres unless the panel is sealed first.
Can MDF FR be formed, bent or molded?
Flat panels can be cold-formed only over large radii; use kerf-cutting, thin flexible MDF or postforming-grade panels for curves, and 3D-embossed doors are produced by membrane-press moulding of routed blanks.
What is the maximum service temperature of MDF FR?
MDF FR is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 622-5 Fibreboards — Specifications, Part 5: Dry process boards (MDF) — CEN (2009)
- ANSI A208.2 Medium Density Fiberboard for Interior Applications — Composite Panel Association / ANSI (2016)
- ASTM D1037 Standard Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials — ASTM (2020)
- ASTM D1554 Standard Terminology Relating to Wood-Base Fiber and Particle Panel Materials — ASTM (2020)
- Wood Handbook — Wood as an Engineering Material, GTR-190, Ch. 11 Wood-Based Composite Materials — USDA Forest Products Laboratory (2010)
- Inventory of Carbon & Energy (ICE) v2 — timber & panel products — University of Bath / Circular Ecology (2011)
- Standard / MR / FR / ultralight MDF panel datasheets — Kronospan, Egger, Medite, Dare Global ( / ) (2024)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.