What is MDF?
The Wood Guide · The wood register
Not solid wood, but wood fibreWhat is MDF?
Medium Density Fibreboard: finely ground wood fibre, bonded with resin and pressed into a dead-straight board. No knots, no warping, and a perfectly smooth finish.
- Uniform and dimensionally stable
- Excellent indoors, not outdoors
- Our interior range and cabinets
MDF in brief
Where solid wood has a will of its own — knots, grain, movement with moisture — MDF is completely predictable. That is both its strength and its limitation.
An MDF board has the same density across its entire surface. There is no direction to it, no knot that tears out, no growth ring that reacts differently. You can rout right up to the edge without anything breaking off, and the surface is so smooth that paint lies perfectly flat on it. For crisp, painted furniture, little can match it.
Our interior range and the new cabinet collection are made of MDF. For a cabinet door that has to stay dead straight for twenty years and take a flawless lacquer finish, solid wood is not the better choice — MDF is.
- What
- wood fibre + resin, pressed together
- Surface
- smooth and even, no grain
- Working
- saws, drills, sands and routs easily
- Finishing
- paint, laminate or veneer
- Indoors
- excellent
- Outdoors
- not suitable
To be fair: moisture is the weak spot. An MDF board that gets wet swells up and never returns to its shape.
Try it
How MDF is made
The raw material is wood that would otherwise go unused: sawdust, chips and offcuts from wood processing.
- DefibratingThe wood waste is mechanically broken down into fine fibres — much finer than the chips in chipboard, which explains the smoother surface.
- MixingThe fibres are mixed with resins and additives into a uniform mass.
- PressingUnder high pressure and temperature the mass is pressed into boards, with the same density across the entire surface.
- FinishingThe boards cool down, are cut to size and sanded to that characteristic smooth surface.
Properties
Physical
Medium density and hardness, and relatively flexible. Easy to work with a saw, drill and sander — and routs right up to the edge without tearing out.
Moisture and chemicals
MDF reacts to moisture and to certain chemicals. Protect it from water: otherwise the board swells and can delaminate.
Thermal
Limited thermal conductivity and not particularly heat-resistant — keep it away from direct heat sources.
Aesthetic
The smooth, even surface is ideal for painting, laminating and veneering. There is no grain to show through the finish.
What MDF is used for
Furniture
Its uniform structure and easy workability make MDF the standard in the furniture industry — especially for lacquered fronts and cabinet sides. See our cabinet collection.
Interior and decoration
Wall panels, ceilings and partition walls, precisely because it takes any finish. View our whole interior range.
Construction
Doors, frames and other components — thanks to its dimensional stability and the ability to rout complex shapes.
Hobby and model making
Pre-cut boards are available everywhere and easy to work; ideal for DIY projects.
Advantages and limitations
Where MDF wins
- Uniform structure, the same density across the whole surface
- Easy to work and rout
- Suitable for almost any finish
- Affordable compared with solid wood
- Made from wood waste that would otherwise go unused
Where it stops
- Sensitive to moisture — swells and delaminates
- Limited heat resistance
- Lower strength than solid wood
- Heavier than you expect in large boards
Sawing and sanding release very fine dust, which can contain formaldehyde and other substances. Work in a well-ventilated space, use dust extraction and wear a dust mask. The same goes for all sheet materials, by the way.
Chipboard uses coarser chips and is cheaper but rougher. HDF is MDF's heavier sibling: denser, stronger and the standard core for laminate flooring. And if it is solid wood you are after, look in the wood register.
Frequently asked questions about MDF
Is MDF real wood?
Yes and no. It is not solid wood, but it is made entirely from wood: finely ground wood fibre, bonded with resin and pressed together. So it is a sheet material — not a tree species.
Can MDF be used outdoors?
No. Moisture is the weak spot: MDF swells and the board can delaminate. For outdoor use, choose solid wood — see the wood register — or a sheet material made specifically for that purpose.
What is the difference between MDF and HDF?
HDF has a higher density: around 30 to 40% heavier and up to 50% stronger. That is why HDF goes into more heavily loaded applications, such as the core of laminate flooring.
Do I need to take precautions when sawing?
Yes. Sawing and sanding release fine dust that can contain formaldehyde and other substances. Work with ventilation and dust extraction, and wear a dust mask.
Can you screw into MDF?
Yes, but always pre-drill — especially into the edge, where the board splits most easily. Preferably use screws made specifically for sheet materials.
From board to furniture
MDF is what goes into our interior range. For outdoors we look to solid wood — both are in the register.
Have a question about your project? Just ask — we're happy to help.
Photos via Wikimedia Commons: Piece of MDF board: even surface and dense cut edge — Joern Allmers, Public domain · Sawn MDF strips with no grain or knots — Vaderluck, CC BY-SA 3.0