Differences between MDF and MDO

MDO stands for Medium Density Overlay whereas MDF stands for Medium Density Fiberboard. These are types of wood panels. At what time of choosing wood materials, the question arises on the best wood materials to use.

When it comes to plywood, there are many types out in the market today, but I’ll do a comparison between MDO and MDF.

The two wood panels are pocket-friendly and easily available, but what are these two types of plywood, their applications, and what differentiates them?

Let’s look at this below.

What is MDO?

Medium density overlay is a type of wood panel that is made using pressed plywood and a resin layer. Pressure and heat are what bonds the resin layer on one or both sides of the surface, and hence the surface is smooth and ideal for painting.

Its overlay consists of over 27% resin, making it resistant to weather conditions such as heat and moisture. MDO is paintable, with its paint layer being thrice more durable than that applied on ordinary plywood.

What is MDO used for?

MDO is durable and can withstand harsh weather conditions, and is, therefore, suitable for use indoors and outdoors. It can be used to make stuff such as signboards to be put on highways or anywhere out in the open, garage doors as it is very strong, as well as safety fences.

Medium density overlay also tends to be easy to work with and can be used by beginners and the novice. One can use it for small house projects such as shelve making.

Furthermore, MDO, when used indoors, can be utilized for making furniture items such as subfloors, walls, and ceilings.

What is MDF?

The medium density fiberboard is also a type of wood panel that uses wood fibre from soft or hardboard. The wood fibre is pressed under high heat and pressure after being mixed with water, resin adhesive, and wax. This makes it cheaper than solid timber, and it is much denser than plywood.

The type of wood used is mainly softwood. Binders for these kinds of boards include melamine urea formaldehyde, phenolic resins, and polymeric diphenylmethane diisocyanate (PMDI). The latter does not emit formaldehyde which is considered a health hazard.

What is an MDF used for?

MDF is much and much weaker in terms of strength and water resistance and is used indoors to make furniture items such as cabinets, tabletops, drawers, wardrobes, cupboards, and shelves.

It is also suitable for use on bathroom and kitchen interiors when coasted with a water-resistant material, as it tends to absorb moisture quite easily which could destroy it.

Other common applications include making of loudspeaker enclosures and in school construction projects as it is very flexible and nicely paintable.

It easily dulls blades, requiring the use of tungsten carbide blades. MDFs come in different types including moisture resistant MDF, ultralight MDF plate, and fire retardant MDF.

Differences between MDF and MDO

When you need to choose between medium density fibre boards (MDO) and medium density overlay (MDO), these are the differences you need to be aware of in order to choose the right plywood.

Durability and strength

MDO is stronger and can be used on places that provide support for heavyweights. MDF is not so strong and will collapse under a lot of weight. In terms of weight, MDF is actually quite heavy, but MDF is denser but lighter.

Resistance to weather conditions

MDO is more weather resistant than MDF because it has a resin layer which is waterproof. Additionally, it can handle friction better than MDF.

MDF absorbs moisture and swells, making it susceptible to mold, termites and other wood-destroying elements.

Where they can be used

MDO can be used outdoors because of their high resistance to conditions such as moisture, while MDF which easily absorbs moisture is best suited for indoor use. However, for indoor areas that are prone to wetness, there are MDFs that are resistant to moisture. You can use those.


MDO is highly priced because of its strength and durability. Both are, however, generally cheaper. You can save cost by using MDO where it is most necessary; for example, outdoors.

Cutting aftermath

MDF lets out a lot of dust, and therefore a mode of dust collection should be put in place as well as proper ventilation when cutting and a thorough after-clean.

Structural support

MDO is made of varying layers of plywood lined perpendicular to each other. This structure gives it more strength compared to MDF which consists of a mixture of wooden fibre, giving it a weak nature.

Safety of cutting

MDF uses materials such as formaldehyde which is considered hazardous, contrary to MDO which uses 100 % waterproof glue. Today, however, you will find more environment friendly MDF materials used in making MDF as well as MDF binders.

These materials include scrap, forest thinnings, scrap, sawmill off-cuts, and scrap. Bamboo and straw fibres are also being used as they are renewable resources.

Frequently asked questions

What are the dangers of working with MDF compared to other products?

MDF produces a lot of dust which is a mixture of soft and hard wood dust, and formaldehyde dust. Soft and hardwood dust are considered to be hazardous to health, causing asthma and other respiratory diseases. Formaldehyde dust is said to be a cancer causative.

What precautions can I take when cutting MDF wood panel?

With the dangerous nature of the dust produced when cutting MDF plywood, some precautions to be taken include wearing of a face mask to avoid eye irritation and dust inhalation, having an effective mode of dust extraction, and proper cleaning with high-quality vacuum cleaners after cutting.

Respiratory protective equipment can also be used, but it should complement some of the above-mentioned dust control measures such as proper cleaning.

Can MDO be painted?

Yes. Proper painting is, however, necessary to allow it to be durable. If well done, it could go for up to ten years. Proper painting involves the use of the right materials and proper prepping of the surface. For better results, use of two primer coats and two finish coats is recommended.


MDO and MDF wood panels are different wood panels that suit different purposes. MDO being the stronger and more weather resistant can be used outdoors and for supporting heavy materials.

On the other hand, MDF is lighter and bend under too much pressure. They also are not weather resistant and are suited for indoor use in places with low moisture content.

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